Primate Thanatology and the Case for Human Exceptionalism

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By Fazale Rana – September 18, 2019

I will deliver this people from the power of the grave;
I will redeem them from death.
Where, O death, are your plagues?
Where, O grave, is your destruction?

Hosea 13:14

It was the first time someone I knew died. I was in seventh grade. My classmate’s younger brother and two younger sisters perished in a fire that burned his family’s home to the ground. We lived in a small rural town in West Virginia at the time. Everyone knew each other and the impact of that tragedy reverberated throughout the community.

I was asked to be a pallbearer at the funeral. To this day, I remember watching my friend’s father with a cast on one arm and another on one of his legs, hobble up to each of the little caskets to touch them one last time as he sobbed uncontrollably right before we lifted and carried the caskets to the waiting hearses.

Death is part of life and our reaction to death is part of what makes us human. But, are humans unique in this regard?

Funerary Practices

Human responses to death include funerary practices—ceremonies that play an integral role in the final disposition of the body of the deceased.

Anthropologists who study human cultures see funerals as providing important scientific insight into human nature. These scientists define funerals as cultural rituals designed to honor, remember, and celebrate the life of those who have died. Funerals provide an opportunity for people to express grief, mourn loss, offer sympathy, and support the bereaved. Also, funerals often serve a religious purpose that includes (depending on the faith tradition) praying for the person who has died, helping his or her soul transition to the afterlife (or reincarnate).

Funerary Practices and Human Exceptionalism

For many anthropologists, human funerary practices are an expression of our capacities for:

  • symbolism
  • open-ended generative manipulation of symbols
  • theory of mind
  • complex, hierarchical social interactions

Though the idea of human exceptionalism is controversial within anthropology today, a growing minority of anthropologists argue that the combination of these qualities sets us apart from other creatures. They make us unique and exceptional.

As a Christian, I view this set of qualities as scientific descriptors of the image of God. That being the case, then, from my vantage point, human funerary practices (along with language, music, and art) are part of the body of evidence that we can marshal to make the case that human beings uniquely bear God’s image.

What about Neanderthals?

But are human beings really unique and exceptional?

Didn’t Neanderthals bury their dead? Didn’t these hominins engage in funerary practices just like modern humans do?

If the answer to these questions is yes, then for some people it undermines the case for human uniqueness and exceptionalism and, along with it, the scientific case for the image of God. If Neanderthal funerary practices flow out of the capacity for symbolism, open-ended generative capacity, etc., then it means that Neanderthals must have been like us. They must have been exceptional, too, and humans don’t stand apart from all other creatures on Earth, as the Scriptures teach.

Did Neanderthals Bury Their Dead?

But, could these notions about Neanderthal exceptionalism be premature? Although there is widespread belief that Neanderthals buried their dead in a ritualistic manner and even though this claim can be attested in the scientific literature, a growing body of archeological evidence challenges this view.

Many anthropologists question if Neanderthal burials were in fact ritualistic. (If they weren’t, then it most likely indicates that these hominins didn’t have a concept of the afterlife—a concept that requires symbolism and open-ended generative capacities.) Others go so far as to question if Neanderthals buried their dead at all. (For an in-depth discussion of the scientific challenges to Neanderthal burials, see the Resources section below.)

Were Neanderthal Burials an Evolutionary Precursor to Human Funerary Practices?

It is not unreasonable to think that these hominins may well have disposed of corpses and displayed some type of response when members of their group died. Over the centuries, keen observers (including primatologists, most recently) have documented nonhuman primates inspecting, protecting, retrieving, carrying, and dragging the dead bodies of members of their groups.1 In light of these observations, it makes sense to think that Neanderthals may have done something similar.

While it doesn’t appear that Neanderthals responded to death in the same way we do, it is tempting (within the context of the evolutionary paradigm) to view Neanderthal behavior as an evolutionary stepping-stone to the funerary practices of modern humans.

But, is this transitional view the best explanation for Neanderthal burials—assuming that these hominins did, indeed, dispose of group members’ corpses? Research in thanatology (the study of dying and death) among nonhuman primates holds the potential to shed light on this question.

The Nonhuman Primate Response to Death

Behavioral evolution researchers André Gonçalves and Susana Caravalho recently reviewed studies in primate thanatology—categorizing and interpreting the way these creatures respond to death. In the process, they sought to explain the role the death response plays among various primate groups.

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Figure 1: Monkey Sitting over the Body of a Deceased Relative. Image credit: Shutterstock

When characterizing the death response of nonhuman primates, Gonçalves and Caravalho group the behaviors of these creatures into two categories: (1) responses to infant deaths and (2) responses to adult deaths.

In most primate taxa (classified groups), when an infant dies the mother will carry the dead baby for days before abandoning it, often grooming the corpse and swatting away flies. Eventually, she will abandon it. Depending on the taxon, in some instances young females will carry the infant’s remains for a few days after the mother abandons it. Most other members in the group ignore the corpse. At times, they will actively avoid both mother and corpse when the stench becomes overwhelming.

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Figure 2: Baboon Mother with a Child. Image credit: Shutterstock

The death of an adult member of the group tends to elicit a much more pervasive response than does the death of an infant. The specific nature of the response depends upon the taxon and also on other factors such as: (1) the bond between individual members of the group and the deceased; (2) the social status of the deceased; and (3) the group structure of the particular taxon. Typically, the closer the bond between the deceased and the group member the longer the duration of the death response. The same is true if the deceased is a high-ranking member of the group.

Often the death response includes vocalizations that connote alarm and distress. Depending on the taxon, survivors may hit and pull at the corpse, as if trying to rouse it. Other times, it appears that survivors hit the corpse out of frustration. Sometimes groups members will sniff at the corpse or peer at it. In some taxa, survivors will groom the corpse or stroke it gently, while swatting away flies. In other taxa, survivors will stand vigil over the corpse, guarding it from scavengers.

In some instances, survivors return to the corpse and visit it for days. After the corpse is disposed, group members may continue to visit the site for quite some time. In other taxa, group members may avoid the death site. Both behaviors indicate that group members understand that an event of great importance to the group took place at the site where a member died.

Are Humans and Nonhuman Primates Different in Degree? Or Kind?

It is clear that nonhuman primates have an awareness of death and, for some primate taxa, it seems as if members of the group experience grief. Some anthropologists and primatologists see this behavior as humanlike. It’s easy to see why. We are moved by the anguish and confusion these creatures seem to experience when one of their group members dies.

For the most part, these scientists would agree that the human response to death is more complex and sophisticated. Yet, they see human behavior as differing only in degree rather than kind when compared to other primates. Accordingly, they interpret primate death awareness as an evolutionary antecedent to the sophisticated funerary practices of modern humans, with Neanderthal behavior part of the trajectory. And for this reason, they maintain that human beings really aren’t unique or exceptional.

The Trouble with Anthropomorphism

One problem with this conclusion (even within an evolutionary framework) is that it fails to account for the human tendency toward anthropomorphism. As part of our human nature, we possess theory of mind. We recognize that other human beings have minds like ours. And because of this capability, we know what other people are thinking and feeling. But, we don’t know how to turn this feature on and off. As a result, we also apply theory of mind to animals and inanimate objects, attributing humanlike behaviors and motivations to them, though they don’t actually possess these qualities.

British ethnologist Marian Stamp Dawkins argues in her book Why Animals Matter that scientists studying animal behavior fall victim to the tendency to anthropomorphize just as easily as the rest of us. Too often, researchers interpret experimental results from animal behavioral studies and from observations of animal behavior in captivity and the wild in terms of human behavior. When they do, these researchers ascribe human mental experiences—thoughts and feelings—to animals. Dawkins points out that when investigators operate this way, it leads to untestable hypotheses because we can never truly know what occurs in animal minds. Moreover, Dawkins argues that we tend to prefer anthropomorphic interpretations to other explanations. She states, “Anthropomorphism tends to make people go for the most human-like explanation and ignore the other less exciting ones.”2

A lack of awareness of our tendency toward anthropomorphism raises questions about the all-too-common view that the death response of nonhuman primates—and Neanderthals—is humanlike and an evolutionary antecedent to modern human funerary practices. This is especially true in light of the explanation offered by Gonçalves and Caravalho for the death response in primates.

The two investigators argue that the response of mothers to the death of their infants is actually maladaptive (from an evolutionary perspective). Carrying around dead infants and caring for them is energetically costly and hinders their locomotion. Both consequences render them vulnerable to predators. The pair explain this behavior by arguing that the mother’s response to the death of her infant falls on the continuum of care-taking behavior and can be seen as a trade-off. In other words, nonhuman primate mothers who have a strong instinct to care for their offspring will ensure the survival of their infant. But if the infant dies, the instinct is so strong that they will continue to care for it after its death.

Gonçalves and Caravalho also point out that the death response toward adult members of the group plays a role in reestablishing new group dynamics. Depending on the primate taxon, the death of members shifts the group’s hierarchical structure. This being the case, it seems reasonable to think that the death response helps group members adjust to the new group structure as survivors take on new positions in the hierarchy.

Finally, as Dawkins argues, we can’t know what takes place in the minds of animals. Therefore, we can’t legitimately attribute human mental experiences to animals. So, while it may seem to us as if some nonhuman primates experience grief as part of the death response, how do we know that this is actually the case? Evidence for grief often consists of loss of appetite and increased vocalizations. However, though these changes occur in response to the death of a group member, there may be other explanations for these behaviors that have nothing to do with grief at all.

Death Response in Nonhuman Primates and Neanderthals

Study of primate thanatology also helps us to put Neanderthal burial practices (assuming that these hominins buried dead group members) into context. Often, when anthropologists interpret Neanderthal burials (from an evolutionary perspective), they are comparing these practices to human funerary practices. This comparison makes it seem like Neanderthal burials are part of an evolutionary trajectory toward modern human behavior and capabilities.

But what if the death response of nonhuman primates is factored into the comparison? When we add a second endpoint, we find that the Neanderthal response to death clusters more closely to the responses displayed by nonhuman primates than to modern humans. And as remarkable as the death response of nonhuman primates may be, it is categorically different from modern human funerary practices. To put it another way, modern human funerary practices reflect our capacity for symbolism, open-ended manipulation of symbols, theory of mind, etc. In contrast, the death response of nonhuman primates and hominins, such as Neanderthals, seems to serve utilitarian purposes. So, it isn’t the presence or absence of the death response that determines our exceptional nature. Instead, it is a death response shaped by our capacity for symbolism and open-ended generative capacity that highlights our exceptional uniqueness.

Modern humans really do seem to stand apart compared to all other creatures in a way that aligns with the biblical claim that human beings uniquely possess and express the image of God.

RTB’s biblical creation model for human origins, described in Who Was Adam?, views hominins such as Neanderthals as creatures created by God’s divine fiat that possess intelligence and emotional capacity. These animals were able to employ crude tools and even adopt some level of “culture,” much like baboons, gorillas, and chimpanzees. But they were not spiritual beings made in God’s image. That position—and all of the intellectual, relational, and symbolic capabilities that come with it—remains reserved for modern humans alone.

Resources for Further Exploration

Did Neanderthals Bury Their Dead?

Nonhuman Primate Behavior

Problem-Solving in Animals and Human Exceptionalism

Endnotes
  1. André Gonçalves and Susana Caravalho, “Death among Primates: A Critical Review of Nonhuman Primate Interactions towards Their Dead and Dying,” Biological Reviews 94, no. 4 (April 4, 2019), doi:10.1111/brv.12512.
  2. Marian Stamp Dawkins, Why Animals Matter: Animal Consciousness, Animal Welfare, and Human Well-Being (New York, Oxford University Press, 2012), 30.

Reprinted with permission by the author

Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/11/21/vocal-signals-smile-on-the-case-for-human-exceptionalism

Timing of Neanderthals’ Disappearance Makes Art Claims Unlikely

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BY FAZALE RANA – MARCH 27, 2019

In Latin it literally means, “somewhere else.”

Legal experts consider an alibi to be one of the most effective legal defenses available in a court of law because it has the potential to prove a defendant’s innocence. It goes without saying: if a defendant has an alibi, it means that he or she was somewhere else when the crime was committed.

As it turns out, paleoanthropologists have discovered that Neanderthals have an alibi, of sorts. Evidence indicates that they weren’t the ones to scratch up the floor of Gorham’s Cave.

Based on recent radiocarbon dates measured for samples from Bajondillo Cave (located on the southern part of the Iberian Peninsula—southwest corner of Europe), a research team from the Japan Agency for Marine-Earth Science and Technology and several Spanish institutions determined that modern humans made their way to the southernmost tip of Iberia around 43,000 years ago, displacing Neanderthals.1

Because Neanderthals disappeared from Iberia at that time, it becomes unlikely that they were responsible for hatch marks (dated to be 39,000 years in age) made on the floor of Gorham’s Cave on the island of Gibraltar. These scratches have been interpreted by some paleoanthropologists as evidence that Neanderthals possessed symbolic capabilities.

But how could Neanderthals have made the hatch marks if they weren’t there? Ladies and gentlemen of the jury: the perfect alibi. Instead, it looks as if modern humans were the culprits who marked up the cave floor.

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Figure 1: Gorham’s Cave. Image credit: Wikipedia

The Case for Neanderthal Exceptionalism

Two of the biggest questions in anthropology today relate to Neanderthals:

  • When did these creatures disappear from Europe?
  • Did they possess symbolic capacity like modern humans, thus putting their cognitive abilities on par with ours as a species?

For paleoanthropologists, these two questions have become inseparable. With regard to the second question, some paleoanthropologists are convinced that Neanderthals displayed symbolic capabilities.

It is important to note that the case for Neanderthal symbolism is largely based on correlations between the archaeological and fossil records. Toward this end, some anthropologists have concluded that Neanderthals possessed symbolism because researchers have recovered artifacts (presumably reflecting symbolic capabilities) from the same layers that harbored Neanderthal fossils. Unfortunately, this approach is complicated by other studies that show that the cave layers have been mixed by either cave occupants (either hominid or modern human) or animals living in the caves. This mixing leads to the accidental association of fossil and archaeological remains. In other words, the mixing of layers raises questions about who the manufacturers of these artifacts were.

Because we know modern humans possess the capacity for symbolism, it is much more likely that modern humans, not Neanderthals, made the symbolic artifacts, in these instances. Then, only through an upheaval of the cave layers did the artifacts mix with Neanderthal remains. (See the Resources section for articles that elaborate this point.)

More often than not, archaeological remains are unearthed by themselves with no corresponding fossil specimens. This is the reason why understanding the timing of Neanderthals’ disappearance and modern humans’ arrival in different regions of Europe becomes so important (and why the two questions interrelate). Paleoanthropologists believe that if they can show that Neanderthals lived in a locale at the time symbolic artifacts were produced, then it becomes conceivable that these creatures made the symbolic items. This interpretation increases in plausiblity if no modern humans were around at the time.

Some researchers have argued along these lines regarding the hatch marks found on the floor of Gorham’s Cave.2 The markings were made in the bedrock of the cave floor. The layers above the bedrock date to between 30,000 and 39,000 years in age. Some paleoanthropologists argue that Neanderthals must have made the markings. Why? Because, even though modern humans were already in Europe by that time, these paleoanthropologists think that modern humans had not yet made their way to the southern part of the Iberian Peninsula. These same researchers also think that Neanderthals survived in Iberia until about 32,000 years ago, even though their counterparts in other parts of Europe had already disappeared. So, on this basis, paleoanthropologists conclude that Neanderthals produced the hatch marks and, thus, displayed symbolic capabilities.

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Figure 2: Hatch marks on the floor of Gorham’s Cave. Image credit: Wikipedia

When Did Neanderthals Disappear from Iberia?

But recent work challenges this conclusion. The Spanish and Japanese team took 17 new radiocarbon measurements from layers of the Bajondillo Cave (located in southern Iberia, near Gorham’s Cave) with the hopes of precisely documenting the change in technology from Mousterian (made by Neanderthals) to Aurignacian (made by modern humans). This transition corresponds to the replacement of Neanderthals by modern humans elsewhere in Europe.

The researchers combined the data from their samples with previous measurements made at the site to pinpoint this transition at around 43,000 years ago—not 32,000 years ago. In other words, modern humans occupied Iberia at the same time they occupied other places in Europe. This result also means that Neanderthals had disappeared from Iberia well before the hatch marks in Gorham’s Cave were made.

Were Neanderthals Exceptional Like Modern Humans?

Though claims of Neanderthal exceptionalism abound in the scientific literature and in popular science articles, the claims universally fail to withstand ongoing scientific scrutiny, as this latest discovery attests. Simply put, based on the archaeological record, there are no good reasons to think that Neanderthals displayed symbolism.

From my perspective, the case for Neanderthal symbolism seems to be driven more by ideology than actual scientific evidence.

It is also worth noting that comparative studies on Neanderthal and modern human brain structures also lead to the conclusion that humans displayed symbolism and Neanderthals did not. (See the Resources section for articles that describe this work in more detail.)

Why Does It Matter?

Questions about Neanderthal symbolic capacity and, hence, exceptionalism have bearing on how we understand human beings. Are human beings unique in our capacity for symbolism or is this quality displayed by other hominins? If humans are not alone in our capacity for symbolism, then we aren’t exceptional. And, if we aren’t exceptional then it becomes untenable to embrace the biblical concept of human beings as God’s image bearers. (As a Christian, I see symbolism as a manifestation of the image of God.)

But, based on the latest scientific evidence, the verdict is in: modern humans are the only species to display the capacity for symbolism. In this way, scientific advance affirms that humans are exceptional in a way that aligns with the biblical concept of the image of God.

The Neanderthals’ alibi holds up. They weren’t there, but humans were. Case closed.

Resources

Endnotes
  1. Miguel Cortés-Sánchez et al., “An Early Aurignacian Arrival in Southwestern Europe,” Nature Ecology and Evolution 3 (January 21, 2019): 207–12, doi:10.1038/s41559-018-0753-6.
  2. Joaquín Rodríguez-Vidal et al., “A Rock Engraving Made by Neanderthals in Gibraltar,” Proceedings of the National Academy of Sciences USA 111, no. 37 (September 16, 2014): 13301–6, doi:10.1073/pnas.1411529111.

Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2019/03/27/timing-of-neanderthals-disappearance-makes-art-claims-unlikely

Did Neanderthals Start Fires?

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BY FAZALE RANA – DECEMBER 5, 2018

It is one of the most iconic Christmas songs of all time.

Written by Bob Wells and Mel Torme in the summer of 1945, “The Christmas Song” (subtitled “Chestnuts Roasting on an Open Fire”) was crafted in less than an hour. As the story goes, Wells and Torme were trying to stay cool during the blistering summer heat by thinking cool thoughts and then jotting them down on paper. And, in the process, “The Christmas Song” was born.

Many of the song’s lyrics evoke images of winter, particularly around Christmastime. But none has come to exemplify the quiet peace of a Christmas evening more than the song’s first line, “Chestnuts roasting on an open fire . . . ”

Gathering around the fire to stay warm, to cook food, and to share in a community has been an integral part of the human experience throughout history—including human prehistory. Most certainly our ability to master fire played a role in our survival as a species and in our ability as human beings to occupy and thrive in some of the world’s coldest, harshest climates.

But fire use is not limited only to modern humans. There is strong evidence that Neanderthals made use of fire. But, did these creatures have control over fire in the same way we do? In other words, did Neanderthals master fire? Or, did they merely make opportunistic use of natural fires? These questions are hotly debated by anthropologists today and they contribute to a broader discussion about the cognitive capacity of Neanderthals. Part of that discussion includes whether these creatures were cognitively inferior to us or whether they were our intellectual equals.

In an attempt to answer these questions, a team of researchers from the Netherlands and France characterized the microwear patterns on bifacial (having opposite sides that have been worked on to form an edge) tools made from flint recovered from Neanderthal sites, and concluded that the wear patterns suggest that these hominins used pyrite to repeatedly strike the flint. This process generates sparks that can be used to start fires.1 To put it another way, the researchers concluded that Neanderthals had mastery over fire because they knew how to start fires.

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Figure 1: Biface tools for cutting or scraping. Image credit: Shutterstock

However, a closer examination of the evidence along with results of other studies, including recent insight into the cause of Neanderthal extinction, raises significant doubts about this conclusion.

What Do the Microwear Patterns on Flint Say?

The investigators focused on the microwear patterns of flint bifaces recovered from Neanderthal sites as a marker for fire mastery because of the well-known practice among hunter-gatherers and pastoralists of striking flint with pyrite (an iron disulfide mineral) to generate sparks to start fires. Presumably, the first modern humans also used this technique to start fires.

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Figure 2: Starting a fire with pyrite and flint. Image credit: Shutterstock

The research team reasoned that if Neanderthals started fires, they would use a similar tactic. Careful examination of the microwear patterns on the bifaces led the research team to conclude that these tools were repeatedly struck by hard materials, with the strikes all occurring in the same direction along the bifaces’ long axis.

The researchers then tried to experimentally recreate the microwear pattern in a laboratory setting. To do so, they struck biface replicas with a number of different types of materials, including pyrites, and concluded that the patterns produced by the pyrite strikes most closely matched the patterns on the bifaces recovered from Neanderthal sites. On this basis, the researchers claim that they have found evidence that Neanderthals deliberately started fires.

Did Neanderthals Master Fire?

While this conclusion is possible, at best this study provides circumstantial, not direct, evidence for Neanderthal mastery of fire. In fact, other evidence counts against this conclusion. For example, bifaces with the same type of microwear patterns have been found at other Neanderthal sites, locales that show no evidence of fire use. These bifaces would have had a range of usages, including butchery of the remains of dead animals. So, it is possible that these tools were never used to start fires—even at sites with evidence for fire usage.

Another challenge to the conclusion comes from the failure to detect any pyrite on the bifaces recovered from the Neanderthal sites. Flint recovered from modern human sites shows visible evidence of pyrite. And yet the research team failed to detect even trace amounts of pyrite on the Neanderthal bifaces during the course of their microanalysis.

This observation raises further doubt about whether the flint from the Neanderthal sites was used as a fire starter tool. Rather, it points to the possibility that Neanderthals struck the bifaces with materials other than pyrite for reasons not yet understood.

The conclusion that Neanderthals mastered fire also does not square with results from other studies. For example, a careful assessment of archaeological sites in southern France occupied by Neanderthals from about 100,000 to 40,000 years ago indicates that Neanderthals could not create fire. Instead, these hominins made opportunistic use of natural fire when it was available to them.2

These French sites do show clear evidence of Neanderthal fire use, but when researchers correlated the archaeological layers displaying evidence for fire use with the paleoclimate data, they found an unexpected pattern. Neanderthals used fire during warm climate conditions and failed to use fire during cold periods—the opposite of what would be predicted if Neanderthals had mastered fire.

Lightning strikes that would generate natural fires are much more likely to occur during warm periods. Instead of creating fire, Neanderthals most likely harnessed natural fire and cultivated it as long as they could before it extinguished.

Another study also raises questions about the ability of Neanderthals to start fires.3 This research indicates that cold climates triggered Neanderthal extinctions. By studying the chemical composition of stalagmites in two Romanian caves, an international research team concluded that there were two prolonged and extremely cold periods between 44,000 and 40,000 years ago. (The chemical composition of stalagmites varies with temperature.)

The researchers also noted that during these cold periods, the archaeological record for Neanderthals disappears. They interpret this disappearance to reflect a dramatic reduction in Neanderthal population numbers. Researchers speculate that when this population downturn took place during the first cold period, modern humans made their way into Europe. Being better suited for survival in the cold climate, modern human numbers increased. When the cold climate mitigated, Neanderthals were unable to recover their numbers because of the growing populations of modern humans in Europe. Presumably, after the second cold period, Neanderthal numbers dropped to the point that they couldn’t recover, and hence, became extinct.

But why would modern humans be more capable than Neanderthals of surviving under extremely cold conditions? It seems as if it should be the other way around. Neanderthals had a hyper-polar body design that made them ideally suited to withstand cold conditions. Neanderthal bodies were stout and compact, comprised of barrel-shaped torsos and shorter limbs, which helped them retain body heat. Their noses were long and sinus cavities extensive, which helped them warm the cold air they breathed before it reached their lungs. But, despite this advantage, Neanderthals died out and modern humans thrived.

Some anthropologists believe that the survival discrepancy could be due to dietary differences. Some data indicates that modern humans had a more varied diet than Neanderthals. Presumably, these creatures primarily consumed large herbivores—animals that disappeared when the climatic conditions turned cold, thereby threatening Neanderthal survival. On the other hand, modern humans were able to adjust to the cold conditions by shifting their diets.

But could there be a different explanation? Could it be that with their mastery of fire, modern humans were able to survive cold conditions? And did Neanderthals die out because they could not start fires?

Taken in its entirety, the data seems to indicate that Neanderthals lacked mastery of fire but could use it opportunistically. And, in a broader context, the data indicates that Neanderthals were cognitively inferior to humans.

What Difference Does It Make?

One of the most important ideas taught in Scripture is that human beings uniquely bear God’s image. As such, every human being has immeasurable worth and value. And because we bear God’s image, we can enter into a relationship with our Maker.

However, if Neanderthals possessed advanced cognitive ability just like that of modern humans, then it becomes difficult to maintain the view that modern humans are unique and exceptional. If human beings aren’t exceptional, then it becomes a challenge to defend the idea that human beings are made in God’s image.

Yet, claims that Neanderthals are cognitive equals to modern humans fail to withstand scientific scrutiny, time and time, again. Now it’s time to light a fire in my fireplace and enjoy a few contemplative moments thinking about the real meaning of Christmas.

Resources

Endnotes

  1. A. C. Sorensen, E. Claud, and M. Soressi, “Neanderthal Fire-Making Technology Inferred from Microwear Analysis,” Scientific Reports 8 (July 19, 2018): 10065, doi:10.1038/s41598-018-28342-9.
  2. Dennis M. Sandgathe et al., “Timing of the Appearance of Habitual Fire Use,” Proceedings of the National Academy of Sciences, USA 108 (July 19, 2011), E298, doi:10.1073/pnas.1106759108; Paul Goldberg et al., “New Evidence on Neandertal Use of Fire: Examples from Roc de Marsal and Pech de l’Azé IV,” Quaternary International 247 (2012): 325–40, doi:10.1016/j.quaint.2010.11.015; Dennis M. Sandgathe et al., “On the Role of Fire in Neandertal Adaptations in Western Europe: Evidence from Pech de l’Azé IV and Roc de Marsal, France,” PaleoAnthropology (2011): 216–42, doi:10.4207/PA.2011.ART54.
  3. Michael Staubwasser et al., “Impact of Climate Change on the Transition of Neanderthals to Modern Humans in Europe,” Proceedings of the National Academy of Sciences, USA 115 (September 11, 2018): 9116–21, doi:10.1073/pnas.1808647115.

When Did Modern Human Brains—and the Image of God—Appear?

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BY FAZALE RANA – NOVEMBER 14, 2018

When I was a kid, I enjoyed reading Ripley’s Believe It or Not! I couldn’t get enough of the bizarre facts described in the pages of this comic.

I was especially drawn to the panels depicting people who had oddly shaped heads. I found it fascinating to learn about people whose skulls were purposely forced into unnatural shapes by a practice known as intentional cranial deformation.

For the most part, this practice is a thing of the past. It is rarely performed today (though there are still a few people groups who carry out this procedure). But for much of human history, cultures all over the world have artificially deformed people’s crania (often for reasons yet to be fully understood). They accomplished this feat by binding the heads of infants, which distorts the normal growth of the skull. Through this practice, the shape of the human head can be readily altered to be abnormally flat, elongated, rounded, or conical.

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Figure 1: Deformed ancient Peruvian skull. Image credit: Shutterstock.

It is remarkable that the human skull is so malleable. Believe it, or not!

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Figure 2: Parts of the human skull. Image credit: Shutterstock.

For physical anthropologists, the normal shape of the modern human skull is just as bizarre as the conical-shaped skulls found among the remains of the Nazca culture of Peru. Compared to other hominins (such as Neanderthals and Homo erectus), modern humans have oddly shaped skulls. The skull shape of the hominins was elongated along the anterior-posterior axis. But the skull shape of modern humans is globular, with bulging and enlarged parietal and cerebral areas. The modern human skull also has another distinctive feature: the face is retracted and relatively small.

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Figure 3: Comparison of modern human and Neanderthal skulls. Image credit: Wikipedia.

Anthropologists believe that the difference in skull shape (and hence, brain shape) has profound significance and helps explain the advanced cognitive abilities of modern humans. The parietal lobe of the brain is responsible for:

  • Perception of stimuli
  • Sensorimotor transformation (which plays a role in planning)
  • Visuospatial integration (which provides hand-eye coordination needed for throwing spears and making art)
  • Imagery
  • Self-awareness
  • Working and long-term memory

Human beings seem to uniquely possess these capabilities. They make us exceptional compared to other hominins. Thus, for paleoanthropologists, two key questions are: when and how did the globular human skull appear?

Recently, a team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, addressed these questions. And their answers add evidence for human exceptionalism while unwittingly providing support for the RTB human origins model.1

The Appearance of the Modern Human Brain

To characterize the mode and tempo for the origin of the unusual morphology (shape) of the modern human skull, the German researchers generated and analyzed the CT scans of 20 fossil specimens representing three windows of time: (1) 300,000 to 200,000 years ago; (2) 130,000 to 100,000 years ago; and (3) 35,000 to 10,000 years ago. They also included 89 cranially diverse skulls from present-day modern humans, 8 Neanderthal skulls, and 8 from Homo erectus in their analysis.

The first group consisted of three specimens: (1) Jebel Irhoud 1 (dating to 315,000 years in age); (2) Jebel Irhoud 2 (also dating to 315,000 years in age); and (3) Omo Kibish (dating to 195,000 years in age). The specimens that comprise this group are variously referred to as near anatomically modern humans or archaic Homo sapiens.

The second group consisted of four specimens: (1) LH 18 (dating to 120,000 years in age); (2) Skhul (dating to 115,000 years in age); (3) Qafzeh 6; and (4) Qafzeh 9 (both dating to about 115,000 years in age. This group consists of specimens typically considered to be anatomically modern humans. The third group consisted of thirteen specimens that are all considered to be anatomically and behaviorally modern humans.

Researchers discovered that the group one specimens had facial features like that of modern humans. They also had brain sizes that were similar to Neanderthals and modern humans. But their endocranial shape was unlike that of modern humans and appeared to be intermediate between H. erectus and Neanderthals.

On the other hand, the specimens from group two displayed endocranial shapes that clustered with the group three specimens and the present-day samples. In short, modern human skull morphology (and brain shape) appeared between 130,000 to 100,000 years ago.

Confluence of Evidence Locates Humanity’s Origin

This result aligns with several recent archaeological finds that place the origin of symbolism in the same window of time represented by the group two specimens. (See the Resources section for articles detailing some of these finds.) Symbolism—the capacity to represent the world and abstract ideas with symbols—appears to be an ability that is unique to modern humans and is most likely a manifestation of the modern human brain shape, specifically an enlarged parietal lobe.

Likewise, this result coheres with the most recent dates for mitochondrial Eve and Y-chromosomal Adam around 120,000 to 150,000 years ago. (Again, see the Resources section for articles detailing some of these finds.) In other words, the confluence of evidence (anatomical, behavioral, and genetic) pinpoints the origin of modern humans (us) between 150,000 to 100,000 years ago, with the appearance of modern human anatomy coinciding with the appearance of modern human behavior.

What Does This Finding Mean for the RTB Human Origins Model?

To be clear, the researchers carrying out this work interpret their results within the confines of the evolutionary framework. Therefore, they conclude that the globular skulls—characteristic of modern humans—evolved recently, only after the modern human facial structure had already appeared in archaic Homo sapiens around 300,000 years ago. They also conclude that the globular skull of modern humans had fully emerged by the time humans began to migrate around the world (around 40,000 to 50,000 years ago).

Yet, the fossil evidence doesn’t show the gradual emergence of skull globularity. Instead, modern human specimens form a distinct cluster isolated from the distinct clusters formed by H. erectus, Neanderthals, and archaic H. sapiens. There are no intermediate globular specimens between archaic and modern humans, as would be expected if this trait evolved. Alternatively, the distinct clusters are exactly as expected if modern humans were created.

It appears that the globularity of our skull distinguishes modern humans from H. erectus, Neanderthals, and archaic Homo sapiens (near anatomically modern humans). This globularity of the modern human skull has implications for when modern human behavior and advanced cognitive abilities emerged.

For this reason, I see this work as offering support for the RTB human origins creation model (and, consequently, the biblical account of human origins and the biblical conception of human nature). RTB’s model (1) views human beings as cognitively superior and distinct from other hominins, and (2) posits that human beings uniquely possess a quality called the image of God that I believe manifests as human exceptionalism.

This work supports both predictions by highlighting the uniqueness and exceptional qualities of modern humans compared to H. erectus, Neanderthals, and archaic H. sapiens, calling specific attention to our unusual skull and brain morphology. As noted, anthropologists believe that this unusual brain morphology supports our advanced cognitive capabilities—abilities that I believe reflect the image of God. Because archaic H. sapiens, Neanderthals, and H. erectus did not possess this brain morphology, it makes it unlikely that these creatures had the sophisticated cognitive capacity displayed by modern humans.

In light of RTB’s model, it is gratifying to learn that the origin of anatomically modern humans coincides with the origin of modern human behavior.

Believe it or not, our oddly shaped head is part of the scientific case that can be made for the image of God.

Resources

Endnotes

  1. Simon Neubauer, Jean-Jacques Hublin, and Philipp Gunz, “The Evolution of Modern Human Brain Shape,” Science Advances 4 (January 24, 2018): eaao596, doi:10.1126/sciadv.aao5961.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/11/14/when-did-modern-human-brains-and-the-image-of-god-appear

Further Review Overturns Neanderthal Art Claim

furtherreviewoverturns

BY FAZALE RANA – OCTOBER 17, 2018

As I write this blog post, the 2018–19 NFL season is just underway.

During the course of any NFL season, several key games are decided by a controversial call made by the officials. Nobody wants the officials to determine the outcome of a game, so the NFL has instituted a way for coaches to challenge calls on the field. When a call is challenged, part of the officiating crew looks at a computer tablet on the sidelines—reviewing the game footage from a number of different angles in an attempt to get the call right. After two minutes of reviewing the replays, the senior official makes his way to the middle of the field and announces, “Upon further review, the call on the field . . .”

Recently, a team of anthropologists from Spain and the UK created quite a bit of controversy based on a “call” they made from working in the field. Using a new U-Th dating method, these researchers age-dated the artwork in caves from Iberia. Based on the age of a few of their samples, they concluded that Neanderthals produced cave paintings.1 But new work by three independent research teams challenges the “call” from the field—overturning the conclusion that Neanderthals made art and displayed symbolism like modern humans.

U-Th Dating Method

The new dating method under review measures the age of calcite deposits beneath cave paintings and those formed over the artwork after the paintings were created. As water flows down cave walls, it deposits calcite. When calcite forms, it contains trace amounts of U-238. This isotope decays into Th-230. Normally, detection of such low quantities of the isotopes would require extremely large samples. Researchers discovered that by using accelerator mass spectrometry, they could get by with 10-milligram samples. And by dating the calcite samples with this technique, they produced minimum and maximum ages for the cave paintings.2

Call from the Field: Neanderthals Are Artists

The team applied their dating method to the art found in three cave sites in Iberia (ancient Spain): (1) La Pasiega, which houses paintings of animals, linear signs, claviform signs, and dots; (2) Ardales, which contains about 1,000 paintings of animals, along with dots, discs, lines, geometric shapes, and hand stencils; and (3) Maltravieso, which displays a set of hand stencils and geometric designs. The research team took a total of 53 samples from 25 carbonate formations associated with the cave art in these three cave sites. While most of the samples dated to 40,000 years old or less (which indicates that modern humans were the artists), three measurements produced minimum ages of around 65,000 years, including: (1) red scalariform from La Pasiega, (2) red areas from Ardales, and (3) a hand stencil from Maltravieso. On the basis of the three measurements, the team concluded that the art must have been made by Neanderthals because modern humans had not made their way into Iberia at that time. In other words, Neanderthals made art, just like modern humans did.

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Figure: Maltravieso Cave Entrance, SpainImage credit: Shutterstock

Shortly after the findings were published, I wrote a piece expressing skepticism about this claim for two reasons.

First, I questioned the reliability of the method. Once the calcite deposit forms, the U-Th method will only yield reliable results if none of the U or Th moves in or out of the deposit. Based on the work of researchers from France and the US, it does not appear as if the calcite films are closed systems. The calcite deposits on the cave wall formed because of hydrological activity in the cave. Once a calcite film forms, water will continue to flow over its surface, leeching out U (because U is much more water soluble than Th). By removing U, water flowing over the calcite will make it seem as if the deposit and, hence, the underlying artwork is much older than it actually is.3

Secondly, I expressed concern that the 65,000-year-old dates measured for a few samples are outliers. Of the 53 samples measured, only three gave age-dates of 65,000 years. The remaining samples dated much younger, typically around 40,000 years in age. So why should we give so much credence to three measurements, particularly if we know that the calcite deposits are open systems?

Upon Further Review: Neanderthals Are Not Artists

Within a few months, three separate research groups published papers challenging the reliability of the U-Th method for dating cave art and, along with it, the claim that Neanderthals produced cave art.4 It is not feasible to detail all their concerns in this article, but I will highlight six of the most significant complaints. In several instances, the research teams independently raised the same concerns.

  1. The U-Th method is unreliable because the calcite deposits are an open system. The concern that I raised was reiterated by two of the research teams for the same reason I expressed. The U-Th dating technique can only yield reliable results if no U or Th moves in or out of the system once the calcite film forms. The continued water flow over the calcite deposits will preferentially leech U from the deposit, making the deposit appear to be older than it is.
  2. The U-Th method is unreliable because it fails to account for nonradiogenic Th. This isotope would have been present in the source water producing the calcite deposits. As a result, Th would already be present in calcite at the time of formation. This nonradiogenic Th would make the samples appear to be older than they actually are.
  3. The 65,000-year-old dates for the three measurements from La Pasiega, Ardales, and Maltravieso are likely outliers. Just as I pointed out before, two of the research groups expressed concern that only 3 of the 53 measurements came in at 65,000 years in age. This discrepancy suggests that these dates are outliers, most likely reflecting the fact that the calcite deposits are an open system that formed with Th already present. Yet, the researchers from Spain and the UK who reported these results emphasized the few older dates while downplaying the younger dates.
  4. Multiple measurements on the same piece of art yielded discordant ages. For example, the researchers made five age-date measurements of the hand stencil at Maltravieso. These dates (66.7 kya [thousand years ago], 55.2 kya, 35.3 kya, 23.1 kys, and 14.7 kya) were all over the place. And yet, the researchers selected the oldest date for the age of the hand stencil, without justification.
  5. Some of the red “markings” on cave walls that were dated may not be art. Red markings are commonplace on cave walls and can be produced by microorganisms that secrete organic materials or iron oxide deposits. It is possible that some of the markings that were dated were not art at all.
  6. The method used by the researchers to sample the calcite deposits may have been flawed. One team expressed concern that the sampling technique may have unwittingly produced dates for the cave surface on which the paintings were made rather than the pigments used to make the art itself. If the researchers inadvertently dated the cave surface, it could easily be older than the art.

In light of these many shortcomings, it is questionable if the U-Th method to date cave art is reliable. After review, the call from the field is overturned. There is no conclusive evidence that Neanderthals made art.

Why Does This Matter?

Artistic expression reflects a capacity for symbolism. And many people view symbolism as a quality unique to human beings that contributes to our advanced cognitive abilities and exemplifies our exceptional nature. In fact, as a Christian, I see symbolism as a manifestation of the image of God. If Neanderthals possessed symbolic capabilities, such a quality would undermine human exceptionalism (and with it the biblical view of human nature), rendering human beings nothing more than another hominin. At this juncture, every claim for Neanderthal symbolism has failed to withstand scientific scrutiny.

Now, it is time for me to go back to the game.

Who dey! Who dey! Who dey think gonna beat dem Bengals!

Resources:

Endnotes

  1. L. Hoffmann et al., “U-Th Dating of Carbonate Crusts Reveals Neandertal Origin of Iberian Cave Art,” Science359 (February 23, 2018): 912–15, doi:10.1126/science.aap7778.
  2. W. G. Pike et al., “U-Series Dating of Paleolithic Art in 11 Caves in Spain,” Science 336 (June 15, 2012): 1409–13, doi:10.1126/science.1219957.
  3. Georges Sauvet et al., “Uranium-Thorium Dating Method and Palaeolithic Rock Art,” Quaternary International 432 (2017): 86–92, doi:10.1016/j.quaint.2015.03.053.
  4. Ludovic Slimak et al., “Comment on ‘U-Th Dating of Carbonate Crusts Reveals Neandertal Origin of Iberian Cave Art,’” Science 361 (September 21, 2018): eaau1371, doi:10.1126/science.aau1371; Maxime Aubert, Adam Brumm, and Jillian Huntley, “Early Dates for ‘Neanderthal Cave Art’ May Be Wrong,” Journal of Human Evolution (2018), doi:10.1016/j.jhevol.2018.08.004; David G. Pearce and Adelphine Bonneau, “Trouble on the Dating Scene,” Nature Ecology and Evolution 2 (June 2018): 925–26, doi:10.1038/s41559-018-0540-4.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/10/17/further-review-overturns-neanderthal-art-claim

Differences in Human and Neanderthal Brains Explain Human Exceptionalism

diffinhumanandneanderthal

BY FAZALE RANA – SEPTEMBER 19, 2018

When I was a little kid, my mom went through an Agatha Christie phase. She was a huge fan of the murder mystery writer and she read all of Christie’s books.

Agatha Christie was caught up in a real-life mystery of her own when she disappeared for 10 days in December 1926 under highly suspicious circumstances. Her car was found near her home, close to the edge of a cliff. But, she was nowhere to be found. It looked as if she disappeared without a trace, without any explanation. Eleven days after her disappearance, she turned up in a hotel room registered under an alias.

Christie never offered an explanation for her disappearance. To this day, it remains an enduring mystery. Some think it was a callous publicity stunt. Some say she suffered a nervous breakdown. Others think she suffered from amnesia. Some people suggest more sinister reasons. Perhaps, she was suicidal. Or maybe she was trying to frame her husband and his mistress for her murder.

Perhaps we will never know.

Like Christie’s fictional detectives Hercule Poirot and Miss Marple, paleoanthropologists are every bit as eager to solve a mysterious disappearance of their own. They want to know why Neanderthals vanished from the face of the earth. And what role did human beings (Homo sapiens) play in the Neanderthal disappearance, if any? Did we kill off these creatures? Did we outcompete them or did Neanderthals just die off on their own?

Anthropologists have proposed various scenarios to account for the Neanderthals’ disappearance. Some paleoanthropologists think that differences in the cognitive capabilities of modern humans and Neanderthals help explain the creatures’ extinction. According to this model, superior reasoning abilities allowed humans to thrive while Neanderthals faced inevitable extinction. As a consequence, we replaced Neanderthals in the Middle East, Europe, and Asia when we first migrated to these parts of the world.

Computational Neuroanatomy

Innovative work by researchers from Japan offers support for this scenario.1 Using a technique called computational neuroanatomy, researchers reconstructed the brain shape of Neanderthals and modern humans from the fossil record. In their study, the researchers used four Neanderthal specimens:

  • Amud 1 (50,000 to 70,000 years in age)
  • La Chapelle-aux Saints 1 (47,000 to 56,000 years in age)
  • La Ferrassie 1 (43,000 to 45,000 years in age)
  • Forbes’ Quarry 1 (no age dates)

They also worked with four Homo sapiens specimens:

  • Qafzeh 9 (90,000 to 120,000 years in age)
  • Skhūl 5 (100,000 to 135,000 years in age
  • Mladeč 1 (35,000 years in age)
  • Cro-Magnon 1 (32,000 years in age)

Researchers used computed tomography scans to construct virtual endocasts (cranial cavity casts) of the fossil brains. After generating endocasts, the team determined the 3D brain structure of the fossil specimens by deforming the 3D structure of the average human brain so that it fit into the fossil crania and conformed to the endocasts.

This technique appears to be valid, based on control studies carried out on chimpanzee and bonobo brains. Using computational neuroanatomy, researchers can deform a chimpanzee brain to accurately yield the bonobo brain, and vice versa.

Brain Differences, Cognitive Differences

The Japanese team learned that the chief difference between human and Neanderthal brains is the size and shape of the cerebellum. The cerebellar hemisphere is projected more toward the interior in the human brain than in the Neanderthal brain and the volume of the human cerebellum is larger. Researchers also noticed that the right side of the Neanderthal cerebellum is significantly smaller than the left side—a phenomenon called volumetric laterality. This discrepancy doesn’t exist in the human brain. Finally, the Japanese researchers observed that the parietal regions in the human brain were larger than those regions in Neanderthals’ brains.

differences-in-human-and-neanderthal-brains
Image credit: Shutterstock

 

Because of these brain differences, the researchers argue that humans were socially and cognitively more sophisticated than Neanderthals. Neuroscientists have discovered that the cerebellum helps motor functions and higher cognition by contributing to language function, working memory, thought, and social abilities. Hence, the researchers argue that the reduced size of the right cerebellar hemisphere in Neanderthals limits the connection to the prefrontal regions—a connection critical for language processing. Neuroscientists have also discovered that the parietal lobe plays a role in visuo-spatial imagery, episodic memory, self-related mental representations, coordination between self and external spaces, and sense of agency.

On the basis of this study, it seems that humans either outcompeted Neanderthals for limited resources—driving them to extinction—or simply were better suited to survive than Neanderthals because of superior mental capabilities. Or perhaps their demise occurred for more sinister reasons. Maybe we used our sophisticated reasoning skills to kill off these creatures.

Did Neanderthals Make Art, Music, Jewelry, etc.?

Recently, a flurry of reports has appeared in the scientific literature claiming that Neanderthals possessed the capacity for language and the ability to make art, music, and jewelry. Other studies claim that Neanderthals ritualistically buried their dead, mastered fire, and used plants medicinally. All of these claims rest on highly speculative interpretations of the archaeological record. In fact, other studies present evidence that refutes every one of these claims (see Resources).

Comparisons of human and Neanderthal brain morphology and size become increasingly important in the midst of this controversy. This recent study—along with previous work (go here and here)—indicates that Neanderthals did not have the brain architecture and, hence, cognitive capacity to communicate symbolically through language, art, music, and body ornamentation. Nor did they have the brain capacity to engage in complex social interactions. In short, Neanderthal brain anatomy does not support any interpretation of the archaeological record that attributes advanced cognitive abilities to these creatures.

While this study provides important clues about the disappearance of Neanderthals, we still don’t know why they went extinct. Nor do we know any of the mysterious details surrounding their demise as a species.

Perhaps we will never know.

But we do know that in terms of our cognitive and social capacities, human beings stand apart from Neanderthals and all other creatures. Human brain biology and behavior render us exceptional, one-of-a-kind, in ways consistent with the image of God.

Resources

Endnotes

  1. Takanori Kochiyama et al., “Reconstructing the Neanderthal Brain Using Computational Anatomy,” Science Reports 8 (April 26, 2018): 6296, doi:10.1038/s41598-018-24331-0.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/09/19/differences-in-human-and-neanderthal-brains-explain-human-exceptionalism

Yeast Gene Editing Study Raises Questions about the Evolutionary Origin of Human Chromosome 2

yeastgeneediting

BY FAZALE RANA – SEPTEMBER 12, 2018

As a biochemist and a skeptic of the evolutionary paradigm, people often ask me two interrelated questions:

  1. What do you think are the greatest scientific challenges to the evolutionary paradigm?
  2. How do you respond to all the compelling evidence for biological evolution?

When it comes to the second question, people almost always ask about the genetic similarity between humans and chimpanzees. Unexpectedly, new research on gene editing in brewer’s yeast helps answer these questions more definitively than ever.

For many people, the genetic comparisons between the two species convince them that human evolution is true. Presumably, the shared genetic features in the human and chimpanzee genomes reflect the species’ shared evolutionary ancestry.

One high-profile example of these similarities is the structural features human chromosome 2 shares with two chimpanzee chromosomes labeled chromosome 2A and chromosome 2B. When the two chimpanzee chromosomes are placed end to end, they look remarkably like human chromosome 2. Evolutionary biologists interpret this genetic similarity as evidence that human chromosome 2 arose when chromosome 2A and chromosome 2B underwent an end-to-end fusion. They claim that this fusion took place in the human evolutionary lineage at some point after it separated from the lineage that led to chimpanzees and bonobos. Therefore, the similarity in these chromosomes provides strong evidence that humans and chimpanzees share an evolutionary ancestry.

yeast-gene-editing-study-1

Figure 1: Human and Chimpanzee Chromosomes Compared

Image credit: Who Was Adam? (Covina, CA: RTB Press, 2015), p. 210.

Yet, new work by two separate teams of synthetic biologists from the United States and China, respectively, raises questions about this evolutionary scenario. Working independently, both research teams devised similar gene editing techniques that, in turn, they used to fuse the chromosomes in the yeast species, Saccharomyces cerevisiae (brewer’s yeast).Their work demonstrates the central role intelligent agency must play in end-on-end chromosome fusion, thereby countering the evolutionary explanation while supporting a creation model interpretation of human chromosome 2.

The Structure of Human Chromosome 2

Chromosomes are large structures visible in the nucleus during the cell division process. These structures consist of DNA combined with proteins to form the chromosome’s highly condensed, hierarchical architecture.

yeast-gene-editing-study-2Figure 2: Chromosome Structure

Image credit: Shutterstock

Each species has a characteristic number of chromosomes that differ in size and shape. For example, humans have 46 chromosomes (23 pairs); chimpanzees and other apes have 48 (24 pairs).

When exposed to certain dyes, chromosomes stain. This staining process produces a pattern of bands along the length of the chromosome that is diagnostic. The bands vary in number, location, thickness, and intensity. And the unique banding profile of each chromosome helps geneticists identify them under a microscope.

In the early 1980s, evolutionary biologists compared the chromosomes of humans, chimpanzees, gorillas, and orangutans for the first time.2 These studies revealed an exceptional degree of similarity between human and chimp chromosomes. When aligned, the human and corresponding chimpanzee chromosomes display near-identical banding patterns, band locations, band size, and band stain intensity. To evolutionary biologists, this resemblance reveals powerful evidence for human and chimpanzee shared ancestry.

The most noticeable difference between human and chimp chromosomes is the quantity: 46 for humans and 48 for chimpanzees. As I pointed out, evolutionary biologists account for this difference by suggesting that two chimp chromosomes (2A and 2B) fused. This fusion event would have reduced the number of chromosome pairs from 24 to 23, and the chromosome number from 48 to 46.

As noted, evidence for this fusion comes from the close similarity of the banding patterns for human chromosome 2 and chimp chromosomes 2A and 2B when the two are oriented end on end. The case for fusion also gains support by the presence of: (1) two centromeres in human chromosome 2, one functional, the other inactive; and (2) an internal telomeresequence within human chromosome 2.3 The location of the two centromeres and internal telomere sequences corresponds to the expected locations if, indeed, human chromosome 2 arose as a fusion event.4

Evidence for Evolution or Creation?

Even though human chromosome 2 looks like it is a fusion product, it seems unlikely to me that its genesis resulted from undirected natural processes. Instead, I would argue that a Creator intervened to create human chromosome 2 because combining chromosomes 2A and 2B end to end to form it would have required a succession of highly improbable events.

I describe the challenges to the evolutionary explanation in some detail in a previous article:

  • End-to-end fusion of two chromosomes at the telomeres faces nearly insurmountable hurdles.
  • And, if somehow the fusion did occur, it would alter the number of chromosomes and lead to one of three possible scenarios: (1) nonviable offspring, (2) viable offspring that suffers from a diseased state, or (3) viable but infertile offspring. Each of these scenarios would prevent the fused chromosome from entering and becoming entrenched in the human gene pool.
  • Finally, if chromosome fusion took place and if the fused chromosome could be passed on to offspring, the event would have had to create such a large evolutionary advantage that it would rapidly sweep through the population, becoming fixed.

This succession of highly unlikely events makes more sense, from my vantage point, if we view the structure of human chromosome 2 as the handiwork of a Creator instead of the outworking of evolutionary processes. But why would these chromosomes appear to be so similar, if they were created? As I discuss elsewhere, I think the similarity between human and chimpanzee chromosomes reflects shared design, not shared evolutionary ancestry. (For more details, see my article “Chromosome 2: The Best Evidence for Evolution?”)

Yeast Chromosome Studies Offer Insight

Recent work by two independent teams of synthetic biologists from the US and China corroborates my critique of the evolutionary explanation for human chromosome 2. Working within the context of the evolutionary framework, both teams were interested in understanding the influence that chromosome number and organization have on an organism’s biology and how chromosome fusion shapes evolutionary history. To pursue this insight, both research groups carried out similar experiments using CRISPR/Cas9 gene editing to reduce the number of chromosomes in brewer’s yeast from 16 to 1 (for the Chinese team) and from 16 to 2 (for the team from the US) through a succession of fusion events.

Both teams reduced the number of chromosomes in stages by fusing pairs of chromosomes. The first attempt reduced the number from 16 to 8. In the next round they fused pairs of the newly created chromosome to reduce the number from 8 to 4, and so on.

To their surprise, the yeast seemed to tolerate this radical genome editing quite well—although their growth rate slowed and the yeast failed to thrive under certain laboratory conditions. Gene expression was altered in the modified yeast genomes, but only for a few genes. Most of the 5,800 genes in the brewer’s yeast genome were normally expressed, compared to the wild-type strain.

For synthetic biology, this work is a milestone. It currently stands as one of the most radical genome reconfigurations ever achieved. This discovery creates an exciting new research tool to address fundamental questions about chromosome biology. It also may have important applications in biotechnology.

The experiment also ranks as a milestone for the RTB human origins creation model because it helps address questions about the origin of human chromosome 2. Specifically, the work with brewer’s yeast provides empirical evidence that human chromosome 2 must have been shaped by an Intelligent Agent. This research also reinforces my concerns about the capacity of evolutionary mechanisms to generate human chromosome 2 via the fusion of chimpanzee chromosomes 2A and 2B.

Chromosome fusion demonstrates the critical role intelligent agency plays.

Both research teams had to carefully design the gene editing system they used so that it would precisely delete two distinct regions in the chromosomes. This process affected end-on-end chromosome fusions in a way that would allow the yeast cells to survive. Specifically, they had to delete regions of the chromosomes near the telomeres, including the highly repetitive telomere-associated sequences. While they carried out this deletion, they carefully avoided deleting DNA sequences near the telomeres that harbored genes. They also simultaneously deleted one of the centromeres of the fused chromosomes to ensure that the fused chromosome would properly replicate and segregate during cell division. Finally, they had to make sure that when the two chromosomes fused, the remaining centromere was positioned near the center of the resulting chromosome.

In addition to the high-precision gene editing, they had to carefully construct the sequence of donor DNA that accompanied the CRISPR/Cas9 gene editing package so that the chromosomes with the deleted telomeres could be directed to fuse end on end. Without the donor DNA, the fusion would have been haphazard.

In other words, to fuse the chromosomes so that the yeast survived, the research teams needed a detailed understanding of chromosome structure and biology and a strategy to use this knowledge to design precise gene editing protocols. Such planning would ensure that chromosome fusion occurred without the loss of key genetic information and without disrupting key processes such as DNA replication and chromosome segregation during cell division. The researchers’ painstaking effort is a far cry from the unguided, undirected, haphazard events that evolutionary biologists think caused the end-on-end chromosome fusion that created human chromosome 2. In fact, given the high-precision gene editing required to create fused chromosomes, it is hard to envision how evolutionary processes could ever produce a functional fused chromosome.

A discovery by both research teams further complicates the evolutionary explanation for the origin of human chromosome 2. Namely, the yeast cells could not replicate unless the centromere of one of the chromosomes was deleted at the time the chromosomes fused. The researchers learned that if this step was omitted, the fused chromosomes weren’t stable. Because centromeres serve as the point of attachment for the mitotic spindle, if a chromosome possesses two centromeres, mistakes occur in the chromosome segregation step during cell division.

It is interesting that human chromosome 2 has two centromeres but one of them has been inactivated. (In the evolutionary scenario, this inactivation would have happened through a series of mutations in the centromeric DNA sequences that accrued over time.) However, if human chromosome 2 resulted from the fusion of two chimpanzee chromosomes, the initial fusion product would have possessed two centromeres, both functional. In the evolutionary scenario, it would have taken millennia for one of the chromosomes to become inactivated. Yet, the yeast studies indicate that centromere loss must take place simultaneously with end-to-end fusion. However, based on the nature of evolutionary mechanisms, it cannot.

Chromosome fusion in yeast leads to a loss of fitness.

Perhaps one of the most remarkable outcomes of this work is the discovery that the yeast cells lived after undergoing that many successive chromosome fusions. In fact, experts in synthetic biology such as Gianni Liti (who commented on this work for Nature), expressed surprise that the yeast survived this radical genome restructuring.5

Though both research teams claimed that the fusion had little effect on the fitness of the yeast, the data suggests otherwise. The yeast cells with the fused chromosomes grew more slowly than wild-type cells and struggled to grow under certain culture conditions. In fact, when the Chinese research team cultured the yeast with the single fused chromosome with the wild-type strain, the wild-type yeast cells out-competed the cells with the fused chromosome.

Although researchers observed changes in gene expression only for a small number of genes, this result appears to be a bit misleading. The genes with changed expression patterns are normally located near telomeres. The activity of these genes is normally turned down low because they usually are needed only under specific growth conditions. But with the removal of telomeres in the fused chromosomes, these genes are no longer properly regulated; in fact, they may be over-expressed. And, as a consequence of chromosome fusion, some genes that normally reside at a distance from telomeres find themselves close to telomeres, leading to reduced activity.

This altered gene expression pattern helps explains the slower growth rate of the yeast strain with fused chromosomes and the yeast cells’ difficulty to grow under certain conditions. The finding also raises more questions about the evolutionary scenario for the origin of human chromosome 2. Based on the yeast studies, it seems reasonable to think that the end-to-end fusion of chromosomes 2A and 2B would have reduced the fitness of the offspring that first inherited the fused chromosome 2, making it less likely that the fusion would have taken hold in the human gene pool.

Chromosome fusion in yeast leads to a loss of fertility.

Normally, yeast cells reproduce asexually. But they can also reproduce sexually. When yeast cells mate, they fuse. As a result of this fusion event, the resulting cell has two sets of chromosomes. In this state, the yeast cells can divide or form spores. In many respects, the sexual reproduction of yeast cels resembles the sexual reproduction in humans, in which egg and sperm cells, each with one set of chromosomes, fuse to form a zygote with two sets of chromosomes.

yeast-gene-editing-study-3

Figure 3: Yeast Cell Reproduction

Image credit: Shutterstock

Both research groups discovered that genetically engineered yeast cells with fused chromosomes could mate and form spores, but spore viability was lower than for wild-type yeast.

They also discovered that after the first round of chromosome fusion when the genetically engineered yeast possessed 8 chromosomes, mating normal yeast cells with those harboring fused chromosomes resulted in low fertility. When wild-type yeast cells were mated with yeast strains that had been subjected to additional rounds of chromosome fusion, spore formation failed altogether.

The synthetic biologists find this result encouraging because it means that if they use yeast with fused chromosomes for biotechnology applications, there is little chance that the genetically engineered yeast will mate with wild-type yeast. In other words, the loss of fertility serves as a safeguard.

However, this loss of fertility does not bode well for evolutionary explanations for the origin of human chromosome 2. The yeast studies indicate that chromosome fusion leads to a loss of fertility because of the mismatch in chromosome number, which makes it difficult for chromosomes to align and properly segregate during cell division. So, why wouldn’t this loss of fertility happen if chromosomes 2A and 2B fuse?

yeast-gene-editing-study-4

Figure 4: Cell Division

Image credit: Shutterstock

In short, the theoretical concerns I expressed about the evolutionary origin of human chromosome 2 find experimental support in the yeast studies. And the indisputable role intelligent agency plays in designing and executing the protocols to fuse yeast chromosomes provides empirical evidence that a Creator must have intervened in some capacity to design human chromosome 2.

Of course, there are a number of outstanding questions that remain for a creation model interpretation of human chromosome 2, including:

  • Why would a Creator seemingly fuse together two chromosomes to create human chromosome 2?
  • Why does this chromosome possess internal telomere sequences?
  • Why does human chromosome 2 harbor seemingly nonfunctional centromere sequences?

We predict that as we learn more about the biology of human chromosome 2, we will discover a compelling rationale for the structural features of this chromosome, in a way that befits a Creator.

But, at this juncture the fusion of yeast chromosomes in the lab makes it hard to think that unguided evolutionary processes could ever successfully fuse two chromosomes, including human chromosome 2, end on end. Creation appears to make more sense.

Resources

Endnotes

  1. Jingchuan Luo et al., “Karyotype Engineering by Chromosome Fusion Leads to Reproductive Isolation in Yeast,” Nature 560 (2018): 392–96, doi:10.1038/s41586-018-0374-x; Yangyang Shao et al., “Creating a Functional Single-Chromosome Yeast,” Nature 560 (2018): 331–35, doi:10.1038/s41586-018-0382-x.
  2. Jorge J. Yunis, J. R. Sawyer, and K. Dunham, “The Striking Resemblance of High-Resolution G-Banded Chromosomes of Man and Chimpanzee,” Science 208 (1980): 1145–48, doi:10.1126/science.7375922; Jorge J. Yunis and Om Prakash, “The Origin of Man: A Chromosomal Pictorial Legacy,” Science 215 (1982): 1525–30, doi:10.1126/science.7063861.
  3. The centromere is a region of the DNA molecule near the center of the chromosome that serves as the point of attachment for the mitotic spindle during the cell division process. Telomeres are DNA sequences located at the tip ends of chromosomes designed to stabilize the chromosome and prevent it from undergoing degradation.
  4. J. W. Ijdo et al., “Origin of Human Chromosome 2: An Ancestral Telomere-Telomere Fusion,” Proceedings of the National Academy of Sciences USA 88 (1991): 9051–55, doi:10.1073/pnas.88.20.9051; Rosamaria Avarello et al., “Evidence for an Ancestral Alphoid Domain on the Long Arm of Human Chromosome 2,” Human Genetics 89 (1992): 247–49, doi:10.1007/BF00217134.
  5. Gianni Liti, “Yeast Chromosome Numbers Minimized Using Genome Editing,” Nature 560 (August 1, 2018): 317–18, doi:10.1038/d41586-018-05309-4.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/09/12/yeast-gene-editing-study-raises-questions-about-the-evolutionary-origin-of-human-chromosome-2

 

Sophisticated Cave Art Evinces the Image of God

sophisticatedcaveart

BY FAZALE RANA – MAY 23, 2018

It’s a new trend in art. Museums and galleries all over the world are exploring the use of sounds, smells, and lighting to enhance the viewer’s experience as they interact with pieces of art. The Tate Museum in London is one institution pioneering this innovative approach to experiencing artwork. For example, on display recently at Tate’s Sensorium was Irish artist Francis Bacon’s Figure in a Landscape, a piece that depicts a gray human figure on a bench. Visitors to the Sensorium put on headphones while they view this painting, and they hear sounds of a busy city. Added to the visual and auditory experiences are the bitter burnt smell of chocolate and the sweet aroma of oranges that engulf the viewer. This multisensory experience is meant to depict a lonely, brooding figure lost in the never-ending activities of a city, with the contrasting aromas simultaneously communicating the harshness and warmth of life in an urban setting.

It goes without saying that designing multisensory experiences like the ones on display at the Sensorium requires expertise in sound, taste, and lighting. This expertise makes recent discoveries on ancient cave and rock art found throughout the world all the more remarkable. As it turns out, the cave and rock art found in Europe, Asia, and Africa are multisensory displays.1 The sophistication of this early art highlights the ingenuity of the first artists—modern humans, who were people just like us.

Cave Art

Though many people have the perception that cave and rock art is crude and simplistic, in fact, it is remarkably sophisticated. For example, the Chauvet-Pont-d’Arc Cave in southern France houses cave art that dates (using carbon-14 measurements) to two periods: 28,000 to 31,000 years ago and 33,500 to 37,000 years ago. These cave sites house realistic depictions of hundreds of animals including herbivores such as horses, cattle, and mammoths. The art also depicts rhinos and carnivores such as cave lions, panthers, bears, and hyenas. The site also contains hand stencils and geometric shapes, such as lines and dots.

The Chauvet Cave human artists painted the animal figures on areas of the cave walls that they polished to make smooth and lighter in color. They also made incisions and etchings around the outline of the painted figures to create a three-dimensional quality to the art and to give the figures a sense of movement.

Multisensory Cave Art

One of the most intriguing aspects of cave art is its location in caves. Oftentimes, the animal figures are depicted deep within the cave’s interior, at unusual locations for the placement of cave paintings.

Recently, archaeologists have offered an explanation for the location of the cave art. It appears as if the artists made use of the caves’ acoustical properties to create a multisensory experience. To say it another way, the cave art is depicted in areas of the caves where the sounds in that area of the cave reinforce the cave paintings. For example, hoofed animals are often painted in areas of the caves where the echoes and reverberations make percussive sounds like those made by thundering hooves when these animals are running. Carnivores are often depicted in areas of the caves that are unusually quiet.

San Rock Art

Recently, researchers have discovered that the rock art produced by the San (indigenous hunter-gatherer people from Southern Africa), the oldest of which dates to about 70,000 years ago, also provides viewers a multisensory experience.2 Archaeologists believe that the art depicted on the rocks reflects the existence of a spirit world beneath the surface. These rock paintings are often created in areas where echoes can be heard, presumably reflecting the activities of the spirit world.

Who Made the Cave and Rock Art?

Clearly, the first human artists were sophisticated. But, when did this sophisticated behavior emerge? The discovery of art in Europe and Asia indicates that the first humans who made their way out of Africa as they migrated around the world carried with them the capacity for art. To put it another way, the capacity for art did not emerge in humans after they reached Europe, but instead was an intrinsic part of human nature before we began to make our way around the world.

The discovery of symbolic artifacts as old as 80,000 years in age in caves in South Africa(artistic expression is a manifestation of the capacity to represent the world with symbols) and the dating of the oldest San rock art at 70,000 years in age adds support to this view.

Linguist Shigeru Miyagawa points out that genetic evidence indicates that the San separated from the rest of humanity around 125,000 years ago. While the San remained in Africa, the group of humans who separated from the San and made their way into Asia and Europe came from a separate branch of humanity. And yet, the art produced by the San displays the same multisensory character as the art found in Europe and Asia. To say it another way, the rock art of the San and the cave art in Europe and Asia display unifying characteristics. These unifying features indicate that the art share the same point of origin. Given that the data seems to indicate that humanity’s origin is about 150,000 years ago, it appears that the origin of art coincides closely to the time that modern humans appear in the fossil record.3

Cave Art and Rock Evince the Biblical View of Human Nature

The sophistication of the earliest art highlights the exceptional nature of the first artists—modern humans, people just like you and me. The capacity to produce art reflects the capacity for symbolism—a quality that appears to be unique to human beings, a quality contributing to our advanced cognitive abilities, and a quality that contributes to our exceptional nature. As a Christian, I view symbolism (and artistic expression) as one of the facets of God’s image. And, as such, I would assert that the latest insights on cave art provide scientific credibility for the biblical view of human nature.

Resources

Endnotes

  1. Shigeru Miyagawa, Cora Lesure, and Vitor A. Nóbrega, “Cross-Modality Information Transfer: A Hypothesis about the Relationship among Prehistoric Cave Paintings, Symbolic Thinking, and the Emergence of Language,” Frontiers in Psychology 9 (February 20, 2018): 115, doi:10.3389/fpsyg.2018.00115.
  2. Francis Thackery, “Eland, Hunters and Concepts of ‘Symapthetic Control’: Expressed in Southern African Rock Art,’ Cambridge Archaeological Journal 15 (2005): 27–35, doi:10.1017/S0959774305000028.
  3. Miyagawa et al., “Cross-Modality Information Transfer,” 115.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/05/23/sophisticated-cave-art-evinces-the-image-of-god

Did Neanderthals Produce Cave Paintings?

didneanderthalsproducecavepaintings

BY FAZALE RANA – APRIL 25, 2018

One time when our kids were little, my wife and I discovered that someone had drawn a picture on one of the walls in our house. Though all of our children professed innocence, it was easy to figure out who the culprit was, because the little artist also wrote the first letter of her name on the wall next to her “masterpiece.”

If only archaeologists had it as easy as my wife and me when it comes to determining who made the ancient artwork on the cave walls in Europe. Most anthropologists think that modern humans produced the art. But, a growing minority of scientists think that Neanderthals were the artists, not modern humans. If anthropologists only had some initials to go by.

In the absence of a “smoking gun,” archaeologists believe they now have an approach that will help them determine the artists’ identity. Instead of searching for initials, researchers are trying to indirectly determine who the artists were by dating the cave art. They hope this approach will work because modern humans did not make their way into Europe until around 40,000 years ago. And Neanderthals disappeared around that same time. So, knowing the age of the art would help narrow down the artists’ identity.

Recently, a team from the UK and Spain have applied this new dating method to art found in the caves of Iberia (southwest corner of Europe). And based on the age of the art, they think that the paintings on the cave walls were produced by Neanderthals, not modern humans.1

Artistic expression reflects a capacity for symbolism. And many people view symbolism as a quality unique to human beings, contributing to our advanced cognitive abilities and reflecting our exceptional nature. In fact, as a Christian, I see symbolism as a manifestation of the image of God. Yet, if Neanderthals possessed symbolic capabilities, such a quality would undermine human exceptionalism (and with it the biblical view of human nature), rendering human beings nothing more than another hominin.

Limitations of Dating Cave Art

Dating cave art is challenging, to say the least. Typically, archaeologists will either: (1) date the remains associated with the cave art and try to establish a correlation, or (2) attempt to directly date the cave paintings using carbon-14 measurements of the pigments and charcoal used to make the art. Both approaches have limitations.

In 2012, researchers from the UK and Spain employed a new technique to date the art found on the walls in 11 caves located in northwest Spain.2 This dating method measures the age of the calcite deposits beneath the cave paintings and those that formed over the artwork, once the paintings had been created. As water flows down cave walls, it deposits calcite. When calcite forms it contains trace amounts of U-238. This isotope decays into Th-230. Normally, detection of such low quantities of these isotopes would require extremely large samples. The researchers discovered that by using accelerator mass spectrometry they could get by with 10-milligram samples.

By dating the calcite samples, they produced minimum and maximum ages for the cave paintings. While most of the 50 samples they took dated to around 25,000 years in age (or more recent than that), three were significantly older. They found a claviform-like symbol that dated to 31,000 years in age. They also found hand stencils that were 37,000 years old and, finally, a red disk that dated to 41,000 years in age.

Most anthropologists believe modern humans made their way into Europe around 40,000 years ago, prompting researchers to suggest that maybe Neanderthals created some of the cave art, “because of the 40.8 ky date for the disk is a minimum age, it cannot be ruled out that the earliest paintings were symbolic expressions of Neanderthals, which were present at Cantabrian Spain until at least 42 ka.”3

Dating the Art from Three Cave Sites in Iberia

Recently, this research team applied the same U-Th dating method to the art found in three cave sites in Iberia: (1) La Pasiega, which houses paintings of animals, linear signs, claviform signs, and dots; (2) Ardales, which contains about 1,000 paintings of animals, along with dots, discs, lines, geometric shapes, and hand stencils; and (3) Maltravieso, which displays a set of hand stencils and geometric designs.

The research team took a total of 53 samples from 25 carbonate formations associated with the cave art in these three cave sites. While most of the samples dated to 40,000 years old or less, three measurements produced minimum ages of around 65,000 years in age, including: (1) red scalariform from La Pasiega, (2) red areas from Ardales, and (3) a hand stencil from Maltravieso. On the basis of the three measurements, the team concluded that the art must have been made by Neanderthals because modern humans had not made their way into Iberia at that time. In other words, Neanderthals made art, just like modern humans did.

Are These Results Valid?

At first glance, it seems like the research team has a compelling case for Neanderthal art. Yet, careful examination of the U-Th method and the results raise some concerns.

First, it is not clear if the U-Th method yields reliable results. Recently, a team from France and the US questioned the application of the U-Th method to date cave art.4 Like all radiometric dating methods, the U-Th method only works if the system to be age-dated is closed. In other words, once the calcite deposit forms, the U-Th method will only yield reliable results if none of the U or Th moves in or out of the deposit. Unfortunately, it does not appear as if the calcite films are closed systems. The calcite films form as a result of hydrological activity in the cave. Once a calcite film forms, water will continue to flow over its surface, leeching out U (because U is much more water soluble than Th). This process will make it seem as if the calcite film and, hence, the underlying artwork is much older than it actually is.

In the face of this criticism, the team from the UK and Spain assert the reliability of their method because, for a few of the calcite deposits, they sampled the outermost surface, the middle of the deposit, and the innermost region. Measurements of these three samples gave ages that matched the expected chronology, with the innermost layer measuring older than the outermost surface. But, as the researchers from France and the US (who challenge the validity of the U-Th method to date cave art) point out, this sampling protocol doesn’t ensure that the calcite is a closed system.

Additionally, critics from France and the US identified several examples of cave art dated by both carbon-14 methods and U-Th methods, noting that the carbon-14 method consistently gives much younger ages than the U-Th method. This difference is readily explained if the calcite is an open system.

Secondly, it seems more plausible that the 65,000-year-old dates are outliers. It is important to note that of the 53 samples measured, only three gave age-dates of 65,000 years. The remaining samples gave dates much younger, typically around 40,000 years in age. Given the concerns about the calcite being an open system, should the 65,000-year-old samples be viewed as mere outliers?

Compounding this concern is the fact that samples taken from the same piece of art give discordant dates, with one of the samples dating to 65,000 years in age and the other two samples dating to be much younger. The team from the UK and Spain argue that the artwork was produced in a patchwork manner. But this explanation does not account for the observation that the artwork appears to be a unified piece.

What Does Neanderthal Biology Say?

The archaeological record is not the only evidence we have available to us to assess Neanderthals’ capacity for symbolism (and advanced cognitive abilities). Scientists can also glean insight from Neanderthal biology.

As I discuss in Who Was Adam?, comparisons of the genomes of Neanderthals and modern humans reveal important differences in a number of genes related to neural development, suggesting that there are cognitive differences between the two species. Additionally, the fossil remains of Neanderthals indicate that their brain development s took a different trajectory than ours after birth. As a result, it doesn’t appear as if Neanderthals experienced much of an adolescence (which is the time that significant brain development takes place in modern humans). Finally, the brain structure of Neanderthals indicates that these creatures lacked advanced cognitive capacity and the hand-eye coordination needed to make art.

On the basis of concerns about the validity of the U-Th method when applied to dating calcite films and Neanderthal brain biology, I remain unconvinced that Neanderthals made cave art, let alone had the capacity to do so. So, to me, it appears as if modern humans are, indeed, the “guilty party.” The entire body of evidence still indicates that they are the ones who painted the walls of caves throughout the world. Though, I doubt either my wife or I will have these early artists scrub down the cave walls as punishment. The cave art is much too precious.

Resources

Endnotes

  1. D. L. Hoffmann et al., “U-Th Dating of Carbonate Crusts Reveals Neanderthal Origin of Iberian Cave Art,” Science 359 (February 23, 2018): 912–15, doi:10.1126/science.aap7778.
  2. A. W. G. Pike et al., “U-Series Dating of Paleolithic Art in 11 Caves in Spain,” Science 336 (June 15, 2012): 1409–13, doi:10.1126/science.1219957.
  3. A. W. G. Pike et al., “U-Series Dating of Paleolithic Art.”
  4. Georges Sauvet et al., “Uranium-Thorium Dating Method and Paleolithic Rock Art,” Quaternary International432 (2017): 86–92, doi:10.1016/j.quaint.2015.03.053.
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/04/25/did-neanderthals-produce-cave-paintings

Are Perforated Shells Evidence for Neanderthal Symbolism?

perforatedshells

BY FAZALE RANA – MARCH 28, 2018

When my kids were little, there was a good chance my wife and I would spend our Saturday afternoons hanging out at Chuck E. Cheese’s, while our children ran wild, celebrating the birthday of one of their friends. They loved it. My wife and I endured the chaos (and the mediocre pizza). Two things that helped me through those Saturday afternoons were:

  1. Watching Chuck E. Cheese sing the birthday song.
  2. Playing the gigantic version of whack-a-mole.

Little did I know then that my fondness for this arcade game would serve me well in my work at Reasons to Believe. Lately, it feels like I’m playing a never-ending game of whack-a-mole, responding to the steady stream of claims that Neanderthals possessed symbolism—claims that inevitably don’t stand up to scientific scrutiny.

Many people view symbolism as a quality unique to human beings, contributing to our advanced cognitive abilities and a reflection of our exceptional nature—in ways that align with the image of God. As a Christian, I see symbolism as a manifestation of the image of God. Yet, if Neanderthals possessed symbolic capabilities, this feature would undermine human exceptionalism (and with it the biblical view of human nature), possibly rendering human beings nothing more than another hominin.

The most recent claim of Neanderthal “symbolism” comes from a research team headed up by the Portuguese archeologist João Zilhão. Based on the dating of a flowstone that caps a deposit from the Cueva de los Aviones site in southeast Spain, these investigators argue that Neanderthals must have possessed symbolism nearly 40,000 years before modern humans displayed this property.1 The researchers age-dated the flowstone, using U and Th isotopes, to about 115,000 to 200,00 years in age. This date indicated to the researchers that the deposits must have been produced by Neanderthals, the only hominins in Iberia at the time. The deposits also harbored several other elements that convinced the researchers of Neanderthals’ capacity for symbolism: (1) red and yellow colorants, (2) ochred and perforated marine shells, and (3) shell containers with residues of pigmentatious materials.

Still, Some Questions Remain . . .

At first glance, the research team’s case for Neanderthal symbolism seems compelling, but with a little additional scientific scrutiny, things become much more muddled.

  • For example, the age of the materials at the Cueva de los Aviones site may well be much younger than 115,000 to 200,000 years in age. An earlier study used radiocarbon methods to age-date food shells at this site to be only 45,000 to 50,000 years old. This dating lines up with the arrival of the first modern humans in Europe.2 While the authors of the most recent study dismiss the younger age, arguing that the amount of the radiocarbon in the shells is at the cusp of the method’s detection limits, this concern does not mean that the radiocarbon result is inaccurate. In fact, I would maintain that it is better to determine the age of the artifacts by directly determining the age-date of specimens taken from the deposit than to try to infer the artifacts’ age from complex geological structures associated with the deposit. Moreover, U/Th dating is susceptible to the influence of water flowing through the system. U is water soluble and Th is not. This difference in solubility means that water flow will remove U from the system, making the sample appear to be older than it is. In other words, geologists must make sure that the flowstone is a closed system before regarding the U/Th-determined age of the flowstone to be secure.
  • Another point of concern has to do with whether or not the pigments and the ochred and perforated marine shells at the Cueva de los Aviones site are a reliable indicator of symbolism. Some archaeologists question whether the mere presence of ochre and other pigment materials at a site reflects symbolic capabilities. For example, one research team that also discovered red ochre at a Neanderthal site, dating to 200,000 years in age, concluded: “In our view, there is no reason to assume that the mere presence of iron oxide at an archaeological site, whether Neanderthal or modern human, implies symbolic behavior.”3 Likewise, the perforation of marine shells does not reflect intentional activity on the part of Neanderthals (or even modern humans). A research team from Poland and the UK have shown that predatory mollusks cause the same type of perforations as humans/hominins and at the same locations on the shell surfaces.4

So, given these concerns, it becomes difficult to conclude with any certainty that Neanderthals displayed symbolism based on this most recent study.

Does the Weight of Archaeological Evidence Support Neanderthal Symbolism?

To be certain, the scientific literature is replete with claims that Neanderthals buried their dead, made art and jewelry, mastered fire, made glue, etc. Hence, some scientists argue that Neanderthals displayed symbolic capabilities and advanced cognitive abilities, just like modern humans. Yet, every one of these claims is disputed and they do not withstand ongoing scientific scrutiny. (See the Resources section below.)

In fact, when the Neanderthal archaeological record is considered in its entirety (the isolated and disputed claims of advanced cognition notwithstanding), a clear and cohesive picture emerges about Neanderthal behavior. Though remarkable creatures, they did not have cognitive abilities on par with modern humans. These creatures were nothing like us.

Ian Tattersall and Noam Chomsky have pointed out that the Neanderthal archaeological record displays little evidence of technological innovation. Neanderthal technology remained largely static from the time they first appeared (around 250,000 to 200,000 years ago) to the time they went extinct (around 40,000 years ago). In contradistinction, an exponential growth in modern human technology has taken place since our inception as a species. According to Tattersall and Chomsky, this explosive rate of innovation is only possible because of our symbolic capacity and is clear evidence that Neanderthals lacked symbolism.5

Are Archaeologists Biased against Human Exceptionalism?

So, then, why are so many claims of Neanderthal symbolism published in the scientific literature? I am of the opinion that these claims are motivated by a desire to undermine the notion of human exceptionalism. It has become increasingly commonplace in some scientific circles to condemn anyone who argues for human exceptionalism as committing an outrageous act of speciesism (with speciesism on par with racism). And what better way to undermine the notion of human exceptionalism and to promote species equality than to make Neanderthals appear just like us?

Unfortunately, the limited archaeological data makes it easy to claim that Neanderthals displayed symbolism—even if they didn’t. As science writer Jon Mooallem has pointed out:

“. . . all sciences operate by trying to fit new data into existing theories. And this particular science [archaeology], for which the “data” has always consisted of scant and somewhat inscrutable bits of rock and fossil, often has to lean on those meta-narratives even more heavily. . . . Ultimately, a bottomless relativism can creep in: tenuous interpretations held up by webs of other interpretations, each strung from still more interpretations. Almost every archaeologist I interviewed complained that the field has become “overinterpreted”—that the ratio of physical evidence to speculation about that evidence is out of whack. Good stories can generate their own momentum.6″

Given this tendency in anthropology, one has to wonder how much an antihuman bias and a commitment to the metanarrative of Neanderthal exceptionalism influences interpretation of the archaeological record. Also, how much do these biases fuel claims about Neanderthal symbolism?

In fact, archaeologist João Zilhão, who headed up the research team that redated the Cueva de los Aviones site, is a well-known champion for Neanderthal exceptionalism.7 Science writer Michael Balter has described Zilhão as “the Neanderthal’s fiercest advocate, taking on any and all suggestions that their mental abilities might have been inferior to those of modern humans.”8 Anthropologists have accused Zilhão and his oft-collaborator Erik Trinkaus of treating Neanderthals as a “stone age minority group in need of affirmative action.”9 In fact, Zilhão’s bias is well-known by other anthropologists. Jean-Jacques Hublin from the Max Planck Institute for Evolutionary Anthropology sees Zilhão on the equivalent of a mission from God. Referring to Zilhão, Hublin notes, “Those who are on a mission from God . . . are those who try to deny any evidence not matching with their personal crusade. The latest debates about Neanderthal abilities are one of the worst examples in which ideological issues have overshadowed scientific advance.”10

Published claims that Neanderthals possessed advanced cognitive capacities like humans usually receive quite a bit of fanfare. However, as in the game of whack-a-mole, once the evidence is carefully examined it doesn’t stand up to scrutiny. Claims of Neanderthal symbolism are almost always made based on a single, isolated find and they arise from highly speculative interpretations of the data at hand. When the full body of scientific evidence about Neanderthal biology and behavior is carefully weighed, it seems highly unlikely that these creatures possessed cognitive capacities on par with modern humans.

Resources

Endnotes

  1. Dirk L. Hoffman et al., “Symbolic Use of Marine Shells and Mineral Pigments by Iberian Neandertals 115,000 Years Ago,” Science Advances 4 (February 22, 2018): eaar5255, doi:10.1126/sciadv.aar5255.
  2. João Zilhão et al., “Symbolic Use of Marine Shells and Mineral Pigments by Iberian Neandertals,” Proceedings of the National Academy of Sciences USA 107 (January 19, 2010): 1023–28, doi:10.1073/pnas.0914088107.
  3. Wil Roebroeks et al., “Use of Red Ochre by Early Neandertals,” Proceedings of the National Academy of Sciences USA 109 (February 7, 2012): 1893, doi:10.1073/pnas.1112261109.
  4. Anna Maria Kubicka et al., “A Systematic Review of Animal Predation Creating Pierced Shells: Implications for the Archaeological Record of the Old World,” PeerJ 5 (2017): e2903, doi:10.7717/peerj.2903.
  5. Johan J. Bolhuis et al., “How Could Language Have Evolved?”, PLoS Biology 12 (August 26, 2014): e1001934, doi:10.1371/journal.pbio.1001934.
  6. Jon Mooallem, “Neanderthals Were People, Too,” New York Times Magazine, January 11, 2017, https://www.nytimes.com/2017/01/11/magazine/neanderthals-were-people-too.html.
  7. Michael Balter, “Neandertal Champion Defends the Reputation of Our Closest Cousins,” Science 337 (August 10, 2012): 642–43, doi:10.1126/science.337.6095.642.
  8. Balter, “Neandertal Champion.”
  9. Balter, “Neandertal Champion.”
  10. Balter, “Neandertal Champion.”
Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2018/03/28/are-perforated-shells-evidence-for-neanderthal-symbolism