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

Why Would God Create a World with Parasites?

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BY FAZALE RANA – JUNE 5, 2019

A being so powerful and so full of knowledge as a God who could create the universe, is to our finite minds omnipotent and omniscient, and it revolts our understanding to suppose that his benevolence is not unbounded, for what advantage can there be in the sufferings of millions of lower animals throughout almost endless time? This very old argument from the existence of suffering against the existence of an intelligent first cause seems to me a strong one; whereas, as just remarked, the presence of much suffering agrees well with the view that all organic beings have been developed through variation and natural selection.1

—Charles Darwin, The Autobiography of Charles Darwin

If God exists and if he is all-powerful, all-knowing, and all-good, why is there so much pain and suffering in the world? This conundrum keeps many skeptics and seekers from the Christian faith and even troubles some Christians.

Perhaps nothing epitomizes the problem of pain and suffering more than the cruelty observed in nature. Indeed, what advantage can there be in the suffering of millions of animals?

Often, the pain and suffering animals experience is accompanied by unimaginable and seemingly unnecessary cruelty.

Take nematodes (roundworms) as an example. There are over 10,000 species of nematodes. Some are free-living. Others are parasitic. Nematode parasites infect humans, animals, plants, and insects, causing untold pain and suffering. But their typical life cycle in insects seems especially cruel.

Nematodes that parasitize insects usually are free-living in their adult form but infest their host in the juvenile stage. The infection begins when the juvenile form of the parasite enters into the insect host, usually through a body opening, such as the mouth or anus. Sometimes the juveniles drill through the insect’s cuticle.

Once inside the host, the juveniles release bacteria that infect and kill the host, liquefying its internal tissues. As long as the supply of host tissue holds out, the juveniles will live within the insect’s body, even reproducing. When the food supply runs out, the nematodes exit the insect and seek out another host.

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Figure 1: An Entomopathogenic Nematode Juvenile. Image credit: Shutterstock

Why would God create a world with parasitism? Could God really be responsible for a world like the one we inhabit? Many skeptics would answer “no” and conclude that God must not exist.

A Christian Response to the Problem of Evil

One way to defend God’s existence and goodness in the face of animal pain and suffering is to posit that there just might be good reasons for God to create the world the way it is. Perhaps what we are quick to label as evil may actually serve a necessary function.

This perspective gains support based on some recent insights into the benefits that insect parasites impart to ecosystems. A research team from the University of Georgia (UGA) recently unearthed one example of the important role played by these parasites.2 These researchers demonstrated that nematode-infected horned passalus beetles (bess beetles) are more effective at breaking down dead logs in the forest than their parasite-free counterparts—and this difference benefits the ecosystem. Here’s how.

The Benefit Parasites Provide to the Ecosystem

The horned passalus lives in decaying logs. The beetles consume wood through a multistep process. After ingesting the wood, these insects excrete it in a partially digested form. The wood excrement becomes colonized by bacteria and fungi and then is later re-consumed by the beetle.

These insects can become infected by a nematode parasite (Chondronema passali). The parasite inhabits the abdominal cavity of the beetle (though not its gastrointestinal tract). When infected, the horned passalus can harbor thousands of individual nematodes.

To study the effect of this parasite on the horned passalus and the forest ecosystem inhabited by the insect, researchers collected 113 individuals from the woods near the UGA campus. They also collected pieces of wood from the logs bearing the beetles.

In the laboratory, they placed each of the beetles in separate containers that also contained pieces of wood. After three months, they discovered that the beetles infected with the nematode parasite processed 15 percent more wood than beetles that were parasite-free. Apparently, the beetles compensate for the nematode infection by consuming more food. One possible reason for the increased wood consumption may be due to the fact that the parasites draw away essential nutrients from the beetle host, requiring the insect to consume more food.

While it isn’t clear if the parasite infestation harms the beetle (infected beetles have reduced mobility and loss of motor function), it is clear that the infestation benefits the ecosystem. These beetles play a key role in breaking down dead logs and returning nutrients to the forest soil. By increasing the beetles’ wood consumption, the nematodes accelerate this process, benefiting the ecosystem’s overall health.

Cody Prouty, one of the project’s researchers, points out “that although the beetle and the nematode have a parasitic relationship, the ecosystem benefits from not only the beetle performing its function, but the parasite increasing the efficiency of the beetle. Over the course of a few years, the parasitized beetles could process many more logs than unparasitized beetles, and lead to an increase of organic matter in soils.”3

This study is not the first to discover benefits parasites impart to ecosystems. Parasites play a role in shaping ecosystem biodiversity and they intertwine with the food web. The researchers close their article this way: “Countering long-standing unpopular views of parasites is certainly challenging, but perhaps evidence like that presented here will be of use in this effort.”4

Such evidence does not “revolt our understanding,” as Darwin might suggest, but instead enhances our insights into the creation and helps counter the challenge of the problem of evil. Even creatures as gruesome as parasites can serve a beneficial purpose in creation and maybe could rightfully be understood as good.

Resources

Endnotes
  1. Charles Darwin, The Autobiography of Charles Darwin: 1809–1882 (New York: W. W. Norton, 1969), 90.
  2. Andrew K. Davis and Cody Prouty, “The Sicker the Better: Nematode-Infected Passalus Beetles Provide Enhanced Ecosystem Services,” Biology Letters 15, no. 5 (2019): 20180842, doi:10.1098/rsbl.2018.0842.
  3. University of Georgia, “Parasites Help Beetle Hosts Function More Effectively,” ScienceDaily (May 1, 2019), https://www.sciencedaily.com/releases/2019/05/190501131435.htm.
  4. Davis and Prouty,“The Sicker the Better,” 3.

Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2019/06/05/why-would-god-create-a-world-with-parasites

Why Would God Create a World Where Animals Eat Their Offspring?

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BY FAZALE RANA – MAY 22, 2019

What a book a Devil’s chaplain might write on the clumsy, wasteful, blundering, low and horridly cruel works of nature!

–Charles Darwin, “Letter to J. D. Hooker,” Darwin Correspondence Project

You may not have ever heard of him, but he played an important role in ushering in the Darwinian revolution in biology. His name was Asa Gray.

Gray (1810–1888) was a botanist at Harvard University. He was among the first scientists in the US to adopt Darwin’s theory of evolution. Asa Gray was also a devout Christian.

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Asa Gray in 1864. Image credit: John Adams Whipple, Wikipedia

Gray was convinced that Darwin’s theory of evolution was sound. He was also convinced that nature displayed unmistakable evidence for design. For this reason, he reasoned that God must have used evolution as the means to create and, in doing so, Gray may have been the first person to espouse theistic evolution.

In his book Darwinia, Asa Gray presents a number of essays defending Darwin’s theory. Yet, he also expresses his deepest convictions that nature is filled with indicators of design. He attributed that design to a type of God-ordained, God-guided process. Gray argued that God is the source of all evolutionary change.

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Gray and Darwin struck up a friendship and exchanged around 300 letters. In the midst of their correspondence, Gray asked Darwin if he thought it possible that God used evolution as the means to create. Darwin’s reply revealed that he wasn’t very impressed with this idea.

I cannot persuade myself that a beneficent & omnipotent God would have designedly created the Ichneumonidæ with the express intention of their feeding within the living bodies of caterpillars, or that a cat should play with mice. Not believing this, I see no necessity in the belief that the eye was expressly designed. On the other hand I cannot anyhow be contented to view this wonderful universe & especially the nature of man, & to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws, with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope & believe what he can.1

Darwin could not embrace Gray’s theistic evolution because of the cruelty he saw in nature that seemingly causes untold pain and suffering in animals. Darwin—along with many skeptics today—couldn’t square a world characterized by that much suffering with the existence of a God who is all-powerful, all-knowing, and all-good.

Filial Cannibalism

The widespread occurrence of filial cannibalism (when animals eat their young or consume their eggs after laying them) and abandonment (leading to death) exemplify such cruelty in animals. It seems such a low and brutal feature of nature.

Why would God create animals that eat their offspring and abandon their young?

Is Cruelty in Nature Really Evil?

But what if there are good reasons for God to allow pain and suffering in the animal kingdom? I have written about good scientific reasons to think that a purpose exists for animal pain and suffering (see “Scientists Uncover a Good Purpose for Long-Lasting Pain in Animals” by Fazale Rana).

And, what if animal death is a necessary feature of nature? Other studies indicate that animal death promotes biodiversity and ecosystem stability (see “Of Weevils and Wasps: God’s Good Purpose in Animal Death” by Maureen Moser, and “Animal Death Prevents Ecological Meltdown” by Fazale Rana).

There also appears to be a reason for filial cannibalism and offspring abandonment, at least based on a study by researchers from Oxford University (UK) and the University of Tennessee.2 These researchers demonstrated that filial cannibalism and offspring abandonment comprise a form of parental care.

What? How is that conclusion possible?

It turns out that when animals eat their offspring or abandon their young, the reduction promotes the survival of the remaining offspring. To arrive at this conclusion, the researchers performed mathematical modeling of a generic egg-laying species. They discovered that when animals sacrificed a few of their young, the culling led to greater fitness for their offspring than when animals did not engage in filial cannibalism or egg abandonment.

These behaviors become important when animals lay too many eggs. In order to properly care for their eggs (protect, incubate, feed, and clean), animals confine egg-laying to a relatively small space. This practice leads to a high density of eggs. But this high density can have drawbacks, making the offspring more vulnerable to diseases and lack of sufficient food and oxygen. Filial cannibalism reduces the density, ensuring a greater chance of survival for those eggs that are left behind. So, ironically, when egg density is too high for the environmental conditions, more offspring survive when the parents consume some, rather than none, of the eggs.

So, why lay so many eggs in the first place?

In general, the more eggs that are laid, the greater the number of surviving offspring—assuming there are unlimited resources and no threats of disease. But it is difficult for animals to know how many eggs to lay because the environment is unpredictable and constantly changing. A better way to ensure reproductive fitness is to lay more eggs and remove some of them if the environment can’t sustain the egg density.

So, it appears as if there is a good reason for God to create animals that eat their young. In fact, you might even argue that filial cannibalism leads to a world with less cruelty and suffering than a world where filial cannibalism doesn’t exist at all. This feature of nature is consistent with the idea of an all-powerful, all-knowing, and all-good God who has designed the creation for his good purposes.

Resources

Endnotes
  1. To Asa Gray 22 May [1860],” Darwin Correspondence Project, University of Cambridge, accessed May 15, 2019, https://www.darwinproject.ac.uk/letter/DCP-LETT-2814.xml.
  2. Mackenzie E. Davenport, Michael B. Bansall, and Hope Klug, “Unconventional Care: Offspring Abandonment and Filial Cannibalism Can Function as Forms of Parental Care,” Frontiers in Ecology and Evolution 7 (April 17, 2019): 113, doi:10.3389/fevo.2019.00113.

Reprinted with permission by the author
Original article at:
https://www.reasons.org/explore/blogs/the-cells-design/read/the-cells-design/2019/05/22/why-would-god-create-a-world-where-animals-eat-their-offspring

Why Did God Create the Thai Liver Fluke?

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BY FAZALE RANA – JULY 11, 2017

The Thai liver fluke causes quite a bit of human misery. This parasite infects fish living in the rivers of Southeast Asia, which, in turn, infects people who eat the fish.

Raw and fermented fish make up a big part of the diet of people in Southeast Asia. For example, in Thailand, a popular culinary item is called sour fish. This “delicacy” is prepared by mixing raw fish with garlic, salt, seasoning, and rice. After rolling the mixture into a ball, it is placed in a plastic bag and left to ferment in the hot sun for several days.

The fermentation process isn’t sufficient to kill the cysts of the Thai liver fluke embedded in the muscles of the infected fish. So, when people eat sour fish (or raw fish), they risk ingesting the parasite.

The Thai Liver Fluke Life Cycle

After ingestion, the cysts open in the digestive track of the human host, releasing the fluke. This parasite travels through the bile duct, making its way into the liver, where it takes up residence.

Once in the liver, the fluke lays eggs that are carried into the host’s digestive track by bile secreted by the liver. In turn, the eggs are released into the environment with human excrement. After being ingested by snails, the eggs hatch, producing larvae that escape from the snail. The free-living larvae infect fish, forming cysts in their skin, fins, and muscle.

Image: Life cycle of Opisthorchis viverrini. Image source: Wikipedia

The Thai liver fluke is a master of disguise, evading the immune system of the human host and living for decades in the liver. Unless the infestation is extreme, people infected with the fluke are completely unaware that they harbor this parasite.

Estimates indicate that 10% of the Thai population is infected with the Thai liver fluke. But in the villages of northern Thailand, where the consumption of raw and fermented fish is higher than in other areas of the country, 45% of the people carry the parasite.

The Thai Liver Fluke and Cancer

The Thai liver fluke can live for several decades in the host’s liver without much consequence. But eventually, the burden of the infection catches up with the human host, leading to an aggressive and deadly form of liver cancer that claims about 26,000 Thai lives each year. Once the cancer is detected, most patients die within a year.

Biomedical researchers think the liver cancer is triggered by the Thai liver fluke, which munches on the host’s liver. Interestingly, the fluke’s saliva contains a protein (called granulin-like protein) that stimulates cell growth and division. These processes help the liver to repair itself after being damaged by the fluke. In effect, the parasite eats part of the liver, supercharges the liver to repair itself, and then eats the new tissue, repeating the cycle for decades. The repeated wounding and repairing of the liver tissue accompanied by rapid cell division eventually leads to the onset of cancer.

The Thai Liver Fluke and God’s Goodness

The problems caused by the Thai liver fluke are not limited to the biomedical arena. This parasite causes theological issues, as well. Why would a good God create the Thai liver fluke? Questions like this one fall under the problem of evil.

Philosophers and theologians recognize two kinds of evil: moral and natural.Moral evil stems from human action (or inaction in some cases). Natural evil proceeds from nature itself—earthquakes, tornadoes, floods, diseases, and the like.

Natural evil seems to present a greater theological challenge than moral evil does. Skeptics could agree that God can be excused for the free-will actions of human beings who violate his standard of goodness, but they reason that natural disasters and disease don’t result from human activity. Therefore, this type of “evil” must be attributed solely to God.

Are Some Forms of Natural Evil Actually Moral Evil?

As I have previously argued, many times natural evil is moral evil in disguise. (See the Resources section below.) In other words, the suffering humans experience stems from human moral failing and poor judgment, not the actual natural phenomenon.

This most certainly seems to be the case when it comes to the Thai liver fluke. Liver cancer caused by parasite infestations would plummet if people stopped eating raw fish and developed better public sanitation systems and practices.

So, is it God’s fault that humans become infected with the Thai liver fluke? Or is it because the people of northern Thailand suffer from poverty and a lack of sanitation—ultimately, conditions caused by human moral failing? Is it God’s fault that people of Southeast Asia develop liver cancer from fluke infestations, when they eat raw and fermented fish instead of properly cooking the meat, knowing the adverse health effects?

Parasites Play a Critical Role in Ecological Systems

Still, the question remains: Why would God create parasites at all?

As it turns out, parasites play an indispensable role in ecosystem health.1 Though these creatures make minor contributions to the biomass of ecosystems, they have a significant effect on several ecosystem parameters, including biodiversity. In fact, some ecologists believe that an ecosystem becomes more robust and functions better as parasite diversity increases.

Considering this insight, a rationale exists as to why God would create the Thai liver fluke to be a member of the ecosystems of the rivers in Southeast Asia. This parasite infects any carnivore (dogs, cats, rats, and pigs) that eats fish from these rivers, not just humans. Undoubtedly infecting these carnivores influences a variety of ecosystem processes, such as species competition, and energy flow through the ecosystem. The harm this parasite causes humans is an unintended consequence of imprudent human activities—not the inherent design of nature.

Parasites and God’s Providence

Remarkably, recent work by scientists from the Australian Institute of Tropical Health and Medicine (AITHM) indicates that the suffering caused by the Thai liver fluke may fulfill a higher purpose—a greater good.

These researchers believe that the Thai liver fluke may hold the key to effectively treat slow- and non-healing wounds caused by diabetes.2

High blood glucose levels associated with diabetes compromise the circulatory and immune systems. This compromised condition inhibits wound repair due to restricted blood flow to the site of the injury. It also makes the wound much more prone to infection.

The AITHM researchers realized that the granulin-like protein produced by the Thai liver fluke could be used to promote healing of chronic wounds because it promotes rapid cell proliferation in the liver. If incorporated into a cream, this protein could be topically applied to the wounds, stimulating wound repair. This treatment would dramatically reduce the cost of treating chronic wounds and significantly improve the treatment outcomes.

Ironically, the properties of the granulin-like protein that make this biomolecule so insidious are exactly the properties that make it useful to treat diabetics’ wounds. To put it another way, the Thai liver fluke is beneficial to humanity.

The idea that God designed nature to be useful for humanity is a facet of divine providence. In Christian theology, this idea refers to God’s continual role in: (1) preserving his creation; (2) ensuring that everything happens; and (3) guiding the universe. The concept of divine providence also posits that when God created the world he built into the creation everything humans (and other living organisms) would need. Accordingly, every good thing that people possess has been provided and preserved by God, either directly or indirectly.

On this basis, as counterintuitive as this may initially seem, it could be argued that as part of his providence, God created the Thai liver fluke for humanity’s use and benefit.

And we know that in all things God works for the good of those who love him, who have been called according to his purpose.

–Romans 8:28

Resources

Endnotes

  1. Peter J. Hudson, Andrew P. Dobson, and Kevin D. Lafferty, “Is a Healthy Ecosystem One that Is Rich in Parasites?” Trends in Ecology and Evolution 21 (July 2006): 381–85, doi:10.1016/j.tree.2006.04.007.
  2. Paramjit S. Bansal et al., “Development of a Potent Wound Healing Agent Based on the Liver Fluke Granulin Structural Fold,” Journal of Medicinal Chemistry 60 (April 20, 2017): 4258–66, doi:10.1021/acs.jmedchem.7b00047.