Genetic Origins

genetics-at-work2

As an aspiring anthropology popularizer I frequently encounter people who ask me why anthropology needs to be popularized.  Anthropologists collect data, analyze the results, publish in academic journals, and eventually some of their findings will be used to update undergraduate textbooks.  What is the point of trying to engage with the rest of the world?

Well, to me this is a very simple question to answer.  Anthropology needs to be popularized because it is the science of our species and the knowledge from this area of scientific inquiry can help people understand what it means to be human.  Unfortunately, the best minds of our field don’t actually popularize anthropology very well; if at all.  I think Barbara King did a great job of pointing this out at the end of one of her recent NPR 13.7 blog posts.

So whenever I am in a position to communicate the most interesting and insightful aspects of my specific subfield, evolutionary anthropology, I jump at the opportunity.  Luckily, I had a chance to listen and discuss recent discoveries from the frontier of molecular anthropology last night with one of the top professors in the field: Esteban Parra. I want to share some of these findings with you.

But first, what is molecular anthropology?

Molecular anthropology is the study of our species at the genetic scale.  Insights from this field of inquiry can help us better understand the connections between ancient and modern populations.  I believe trying to understand our connection to the past is something that humans have always done.  And like many things we do, it appears to be uniquely human.  It doesn’t matter how many words in sign language you teach a chimpanzee, they never ask “where did I come from?”

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1000 Genomes Project

But luckily for all of us endlessly curious humans, molecular anthropologists have uncovered a great deal about our origins.  And the technologies utilized by molecular anthropologists have been advancing at such a remarkably quick pace, that new discoveries are made every year that reveal insights into our relationship to the past.  For me, learning about our origins can be as humbling as learning about quantum superpositionmitosis, or the expansion of the universe.   So I hope you get as much out of this article as I got out of my conversation last night.

There are 38 million variants of difference within our species

The Human Genome Project was completed in 2000.  But that was just the beginning.  After sequencing one human genome we had no idea what type of genetic variation there was within our species.  However, the 1000 Genomes Project is the first phase of molecular anthropological research that is attempting to answer that question.  Current data indicates that of the 3 billion base pairs within the human genome, there are 38 million variants of difference within our species.  Surprisingly, most of these variants of difference only appear in one or two people, or one or two populations.

800px-Genetic_Variation

This was originally perplexing to researchers.  Why were most unique variants restricted to such small scales within our species?  The answer: our demographic explosion.

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Within the past two centuries our population has ballooned from one billion to seven billion.  And with population growth comes an increase in mutation rate.  However, all of the unique genetic variants that have resulted from this increased mutation rate have had no opportunity to spread throughout our species because they have all arisen within the past few generations.  As a result, rare variants are largely constrained to continents, and most of those variants are constrained to specific populations, and even individuals.  This should create an even greater impetus to expand the 1000 Genomes Project and incorporate all human populations in the analysis.

Humans are much less genetically diverse than the great apes

Family-tree

recently wrote an article about how understanding chimpanzee genetic diversity may be a key to help conservation efforts throughout Africa.  As it turns out, chimpanzees, bonobos, gorillas, and orangutans are all more genetically diverse species than humans.  This is an incredible discovery. How can a population as phenotypically diverse as human beings with seven billion individuals, be more genetically homogenous than species with low phenotypic diversity and fewer than a million individuals?  This is something I’ve touched on in the past, and it has to do with a) the age of our lineage and b) our rate of migration.

Our species is actually young on evolutionary timescales.  Anatomically modern humans emerged in East Africa between 150,000-200,000 years ago.  Chimpanzees, bonobos, gorillas, and orangutans have all been in existence for hundreds of thousands of years longer than that.  As a consequence, we are far less diverse in comparison.  Another important factor, is that humans migrate quickly when compared to the great apes.  Consequently our rate of gene flow between populations is much higher than between populations of great apes.  Gene flow always decreases diversity and genetically homogenizes a species, and as it turns out, our species is a great case example of that effect.

Founder effect dictates degrees of human genetic diversity within our species

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Founder effects generate genetic bottlenecks.  In order to imagine this, picture that you have one large population, and a few individuals within that population separate from the mother group and start a new population that interacts only indirectly with the parent population.  The population that separated from the parent population will have relatively lower genetic diversity than the mother population because a few individuals will now represent the birth of a new, relatively distinct gene pool.  With enough time and a high degree of isolation, this is how new species usually form.  However, the founder effect for humans has been so rapid that it just created decreased genetic diversity for each founding group.  As a result a decrease in genetic diversity is correlated with temporal patterns of continent-sized human migration events.  The following is a representation of most genetic diversity to least genetic diversity by continent:

Africa > Europe/Middle East/South Asia > East Asia > Oceania > Americas

Molecular anthropologists already knew that the oldest human lineages and the most diverse human lineages were in Africa.  This made intuitive sense because East Africa was the birthplace for our species.  However, it was interesting to find that subsequent founder effects continually decreased genetic diversity throughout our species.

Neanderthals and Denisovans were technically modern humans

humans

We’ve all heard of Neanderthals, and we have all heard narratives explaining the likely relationships between our species and theirs.  But recent insights have indicated Neanderthals contributed to the modern human gene pool. In fact, all non-Africans share approximately 1-4% of their genes with Neanderthals.  That is not much, but it is evidence of interbreeding.  So were they really a separate species?  Well, that depends on your classification scheme.  But since we interbred and produced fertile offspring, imagining them as a distinct population may be superficial.  This could be massively relevant information in regards to current debates stimulated by geneticist George Church.

Interestingly, these genetic insights also give us insight in terms of where interbreeding occurred.  Since Neanderthal genes are equally distributed among all non-Africans, interbreeding likely occurred in the Middle East, not Europe.  If interbreeding occurred in Europe, we should expect contemporary Europeans to have higher frequencies of Neanderthal genes than other non-African populations.  However, since the distribution is even, the first human migrants out of Africa likely interbred with Neanderthals, and carried those genes with them into Asia, Australia, Europe and the Americas.

Denisovans are a lesser known hominid.  They were recently discovered and their genome was sequenced last year.  We know that they lived in Siberia (but we don’t know their full range).  We also know that they are sister taxa to the Neanderthals, but they are still genetically unique enough to have been classified as a different species.  However, like Neanderthals, we know that modern humans had sex and produced fertile offspring with them.  Interestingly, Denisovan genetic variants appear at higher frequencies within Australian aborigine populations.  As a result of this finding, it is likely that the first migrants to journey through Asia to Australia interbred with Denisovans along the way.  Similarly to our situation with understanding Neanderthal taxonomic classification, these results indicate that Denisovans were also modern humans, that were just as ancient as the Neanderthal lineage.

Understanding what it means to be human

So is their a need to popularize anthropology?  I hope this article was a brief example of the benefits of communicating anthropological knowledge to a wider audience.  Insights in all subfields provide us with an opportunity to contemplate our past, and gain a better understanding of our current world. In the future, anthropological research should continue to uncover clues from the past that can help us to piece together our origin.  If learning about human genetics was new, I hope that it piqued your curiosity about where we came from and about what we can learn from anthropological inquiry.

Love anthropology?  Follow Cadell Last on Twitter for anthro-related ramblings!

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Evolution of Suicide

I recently came across an article in the Guardian by Jane Powell about male suicide rates.  Specifically, Powell noted that of the 51,401 suicides in England and Wales from 2001-2011, 38,621 of them were of males over the age of 15.

Jaw-dropping statistics like that are sobering, and reveal that suicide really is a “gender issue.”  Throughout the article she explains why she thinks this is the case:

“Poverty and mental health issues affect both genders. The variable factor is culture and society; how we expect men to act, and how they feel they can behave. Suicide prevention work must, therefore, address this. Men, regardless of age group, often don’t recognise when they are depressed. Depression in men is likely to be signalled by anger, so won’t be recognised either by men themselves or by women as depression. Ironically, they may end up in jail rather than a GP’s surgery. For a man to ask for help is seen as failure, because by convention men are supposed to be in control at all times.”

— Jane Powell

As a male, I didn’t really know what to think of Powell’s explanation.  Are men committing suicide at dramatically higher rates just because of stereotypically-masculine social norms?  After analyzing my own psychology, I became more conflicted.  I believe I am a male with a relatively high emotional intelligence; does that mean I am at lower risk for committing suicide in the future? For some reason I became skeptical that it was that simple.

Powell isn’t the first person to realize that males commit suicide at higher rates than females.  In the 19th century, sociology pioneer Émile Durkheim discovered that males (especially middle-aged unmarried males) committed suicide at much higher rates than females.  If these trends have been consistent over time, and across populations, I started to wonder if evolution had any answers to this suicide disparity.

Among evolutionary scientists suicide is an extremely complicated and controversial topic.  Not only is suicide difficult to study, it also appears to contradict basic evolutionary theory.  If evolutionary processes program organisms to survive and reproduce, how could something as detrimental as suicide be selected for?

Some theorists believe they have solved this issue by applying suicide to concepts of inclusive fitness.  In highly social organisms, suicide should become adaptive when future reproductive potential is low and continued existence is a detriment to the reproductive success of close kin.  This theory, first proposed by Denys deCatanzaro, is still championed by some evolutionary biologists today.  But is there evidence for it?  And can it tell us anything about high rates of male suicide in contemporary times?

There is some evidence that highly social animals like bees commit suicide.  Whenever a bee stings another organism, it tries to pull its stinger out and fly away.  However, as a result it ends up pulling out its innards and dies.  Also, when a bee is parasitized by conopoid flies, they abandon their colony and fly off into isolation to die.  In both cases, deCatanzaro’s theory of suicide seems to be supported.  The bee is protecting the hive from predators and a disease outbreak, and by extension, its own genes.  But are these examples of suicide?  And do they have any relevance to human behaviour?

In order to find out, it is best to look at the data collected from non-human primate researchers.  Although no specific study has been conducted, there has never been a confirmed case of non-human primate suicide.  In certain stressful, artificial environments (e.g., biomedical laboratories, zoos, etc.) there are documented cases of self-injurious behaviour (SIB).  However, no primate has ever engaged in self-inflicted lethal displays. As psychologist Jesse Bering stated:

“There are no cases in which a chimpanzee has been observed to climb the highest branch it could find—and jump.”

— Jesse Bering

This is a big blow to evolutionary theories that claim suicide is adaptive.  If deCatanzaro’s hypothesis is correct, there are a number of highly social primates that should have suicide rates.  To me, this evidence seems to suggest that what we observe in highly social animals like bees isn’t analogous to human suicide.  After all, the examples of bee suicide seem to be more suitably compared to a human dying for a nation-state in combat, or voluntarily quarantining him/herself after contracting a deadly disease.

Another theory that I think comes closer to explaining the origins of human suicide proposes that suicide acts as a social red flag.  This theory proposes that suicide is a by-product of selected deep sadness.  If this theory is correct we should expect the attempted suicide rate to be higher than the suicide rate, and we should also expect kin-support after a suicide attempt to be significantly higher than normal.  Interestingly, this theory is overwhelmingly supported by data collected over the past decade.  Attempted suicide is much more frequent than “successful” suicide.  And after a suicide attempt many close kin usually do step in and try and make that individuals life better.

But what about the gender issue?  If suicide is an evolutionary by-product of deep sadness acting as a red flag for close kin’s support, why do we see suicide gender differences in contemporary times?

Interestingly, Powell’s initial assessment may be right; culture seems to play a massive role in determining gender differences in suicide rate.  This can best be illustrated by the fact that males have a high suicide rate in western countries, but in some areas of the world (e.g., China, Afghanistan) female suicide rate is higher.  Also, females typically attempt suicide at the same rate as males, but are less “successful.”  This could be because males typically attempt suicide through more effective violent means (e.g, guns, knives, etc.), whereas females typically attempt by overdosing on medications.

This may mean that the current high rate of male suicide in the western world, could be reduced through culture.  As Powell noted, men that seek help in western society are currently seen as failures.  If I am any indication, I hope that this type of masculine social conditioning is deteriorating.  I know that I personally have no problem seeking help (medical or otherwise) if I need it, and I try and surround myself with a positive support network that I can lean on when I’m down.  I do not feel any weaker or “less of a man” because I can discuss my emotions and feelings.  I hope that other men can adopt this perspective.  If they do, perhaps suicide will cease to be a gender issue in the western world during my lifetime.

Evolution has provided us with massive brains.  More so than any other animal, we are aware that we are alive.  Consequently, we are also more aware than any other animal that we can end our own lives.  However, we should be thankful that current data seem to indicate that suicide itself is not adaptive; it seems to be a last resort effort for us to reach out for help.  It also seems promising that males are not biologically destined to always suffer from higher rates of suicide.  With that knowledge, it makes it all the more imperative that we create a culture that is open and mature enough for both sexes to feel comfortable discussing emotions and feelings.  Nobody should be made to feel inadequate for feeling depressed.  Suicide is a serious issue, and I think the current gender disparity in suicide rates demands more attention from all of us.

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The Real Culture Wars

culture wars

When we think of culture, we tend to think about material products of human civilization and/or variation of traditions, rituals, and beliefs between different human populations. And of course, these are products of human culture. But does culture distinguish humans from all other animals? Are any other animals cultural? These questions have produced a “culture war” within academia that has deep implications for how we imagine what it means to be human.

Surprisingly, our contemporary understanding of culture is quite new. It was developed during the as a way for European intellectuals to describe differences in human behaviour throughout the world (Tomasello, 1994). The term wasn’t necessary in the same way during the pre-modern era because cultural diffusion was largely constrained by geography. As a result, very few people knew, or interacted with, people from vastly different cultural backgrounds.

Either way, throughout modern intellectual history, the term “culture” has been used as a defining characteristic of the human species. But is it? Are there behavioural patterns in animal communities that evolve and are transmitted in analogous ways to human societies?

Clues that we were not the only species to possess culture came from early studies of our closest relatives: chimpanzees. In the 1960s, primatologist Jane Goodall observed chimpanzees at Gombe Stream National Park making and using tools. At that time humans were defined as “man the tool maker.” After she told her mentor, paleoanthropologist Louis Leakey about her discovery, he famously replied:

“Now we have to redefine man, redefine tool, or accept chimpanzee as human.”

— Louis Leakey

Of course, under any taxonomic classification scheme it would be foolish to redefine chimpanzees as humans, so we instead reclassified our species. We were no longer the only species that made and used tools, but did that also mean we were not the only species to possess culture?

As the top evolutionary scientists in the field pondered this question, it became evident that culture was a more complex term than had previously been thought. What was culture exactly? And if our closest relatives made tools, what else could they do?

Researchers without a clear grasp on what it meant to call a non-human cultural, started to refer to chimpanzee behaviour as “pre-cultural” or “proto-cultural.“ However, others were skeptical of this classification and believed they were observing cultural beings.

Here is an example of one such observation from the field notes of primatologist Christophe Boesch (1985):

“Nova inserts her index finger in the soft soil and then sniffs it carefully. She starts removing slowly a layer of the soil so as not to alert the driver ants in their nest. She breaks a small branch of a sapling and cuts it with her teeth to produce a stick about 30 cm long. She starts dipping it quietly up to 2-3 cm into the nest entrance, watching as the ants climb up the tool. Once they have reached about 10 cm up the tool, she rapidly turns the end of the stick upwards into her mouth, hastily chewing the ants, and then dipping further.”

— Christophe Boesch

Boesch was observing the practice of “ant fishing.” He knew that not all chimpanzee populations knew how to fish for ants. This was a population-specific behaviour. Afterwards, he wondered: how do such population specific behaviours appear? And do they represent chimpanzee cultures? (Boesch, 1996).

Primatological inquiry into these questions met resistance within anthropology. But evolutionary biologists were making equally perplexing discoveries in other species. Research on cetaceans like whales, dolphins, and porpoises, as well as birds like sparrows, starlings, and crows, revealed they possessed population-specific vocalizations and feeding behaviours that appeared to be socially transmitted.

These were thought-provoking results, but were these behaviours cultural? Using social transmission as the only criteria for culture allowed biologists like Charles Lumsden and Edward Wilson to conclude that more than 10,000 species, including some bacteria, could be deemed “cultural.”

The culture wars were just starting.

Cultural anthropologists were unconvinced by all these data and reasoning. They insisted that linguistic mediation was the key to achieving culture. They further argued that imitation of other members of a group couldn’t be correlated with culture.

Discussion of animal culture was becoming polarized, and evolutionary anthropologists were stuck in the middle. An understanding of the human condition was at stake.

In an attempt to break this stalemate, primatologists proposed a “nonarbitrary definition.” (Laland & Hoppit, 2003). This definition sought to incorporate the importance of context; imitation alone was not enough. Also, in order to claim that a behaviour was cultural, researchers first needed to control for ecological and biological determinants of behavioural observations.

In order to apply these ideas to field research, primatologists developed the “method of exclusion.” By using this method, researchers would document behaviours between groups and then infer whether what they were observing was cultural by eliminating any possible ecological and/or genetic cause for its occurrence.

A big breakthrough in this research came in 1999, when several evolutionary scientists from six different long-term chimpanzee field sites compiled their behavioural data and attempted to determine how much cultural variation there was between chimpanzee populations in Africa (Whiten et al., 1999).

Their results were startling. They found 39 different behavioural patterns, including tool usage, grooming and courtship behaviours that appeared to be unconnected to either ecological or biological determinants.

cultural variation

From: Cultures in Chimpanzees

For example, chimpanzees at Budongo, Mahale, and Tai Forest performed rain dances. Chimpanzees at Gombe and Kibale had developed traditions for inspecting wounds and removing parasites (a form of self-medication now termed zoopharmacognosy). Other groups had different feeding traditions; in the west chimps frequently constructed anvils to break open nuts and constructed tools to fish for ants. In the east, they developed different tools to fish for termites. Their was also extreme variation in different social traditions and courtship rituals.

These results indicated that not only were chimpanzees cultural, but the complexity of their culture was without parallel throughout the rest of the animal kingdom. Research over the past decade has validated their results and increased our understanding of cultural variation within our closest relatives. For example, one group of western chimpanzees in Senegal constructs spears to hunt other primates (Pruetz & Bertolani, 2007). The ability to construct spears is taught, and context for the use of the spear is the difference between life and death.

Theorists that accept these discoveries as proof of culture in animals have now moved past the simple cultural dichotomy erected during the culture wars. If chimpanzees and other animals possess complex culture, what makes us so different?

Although research into the question of cultural complexity is still in its infancy, some research believe that the key is the cultural “ratchet effect.” Human culture appears to be characterized by a generational increase in complexity and/or efficiency. These is little evidence that any other animals have ratcheting culture.

Of course, we have been wrong before. If scientists had a chance to studyAustralopithecus africanus or Homo erectus they might have concluded that those species had no ratcheting culture just because of how slow and gradual complexity evolved in their technologies and traditions. For example, Homo erectus tool technology remained remarkably stagnant over a period of one million years. Therefore, future research on generational transmission of culture within and between groups may reveal new insights. Also, there are many chimpanzee populations that have never been studied, and research on other great apes like gorillas, bonobos, and orangutans, has only just begun. As is typical of scientific inquiry, one answer, usually leads to even more interesting and perplexing questions.

The understanding of what culture is, and what separates human culture from animal culture, is one of the most important aspects of our quest to understand the human condition. Exploring these questions is the point of The Ratchet.

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Are Chimpanzees Fair?

Originally posted by Jane Goodall Institute of Canada’s Change Is In You Blog

Humans care about fairness.  I know for me personally, if there are a limited number of resources (e.g., food, shelter), I would feel bad making a decision that gave me more resources at the expense of a close friend or family member.  Of course, that is an anecdotal example of human fairness, but it has been studied scientifically!

Researchers have studied this scientifically by designing “the ultimatum game.”  This game tests whether humans always act in their material self-interest.  In the game, one person must decide how to divide a sum of money and/or resources between two people.  The first person (proposer) makes a proposal, and the second player (responder) either accepts or rejects the proposal.  If the responder rejects the proposal, both players receive nothing.  When human adults play this game, they typically split the resources equally.  This demonstrates that humans are sensitive to fairness.  However, primatologists are still unsure of whether our closest relatives, chimpanzees and bonobos, behave in the same way.

In order to find out, researchers from the University of London decided teach a modified ultimatum game to chimpanzees and bonobos (Kaiser, I. et al., 2012).  Individual apes were exposed to two different food resources: their own, and another individual’s.  In each scenario, one ape had to make a decision of whether to eat their own food, or to eat their own food and steal the other individual’s food.  The team found that neither chimpanzees nor bonobos cared about fairness in this experiment and generally stole a portion of food.  They concluded that “our sense of fairness” must be a derived trait (meaning that it was absent in the human/chimp/bonobo common ancestor).

Open and shut case right?  Perhaps not.

A team of researchers at Yerkes National Primate Center led by primatologists Darby Proctor and Frans de Waal decided to design their own ultimatum game to re-test the hypothesis that our sense of fairness is derived (Procotor & de Waal, 2013).  The study was conducted with six adult chimpanzees and the ultimatum game was much more similar to the human-version of the ultimatum game when compared to the Kaiser et al. study.  The chimpanzees had to choose between coloured tokens that could be exchanged for food rewards.  One token offered equal rewards to both players.  However, a second token would give more resources to the player proposing the deal, at the expense of resources allocated to the second player.  No food reward would be given until both individuals agreed to use one of the two coloured tokens.

So what did the results show?  Chimpanzees behaved in the same way adult humans do.  When a partner’s cooperation was required, they would allocate resources fairly.  So it seems that Kaiser et al. may have prematurely concluded that fairness is a derived behaviour for modern humans.  In retrospect, it shouldn’t be surprising that chimpanzees display empathy and act fairly to one another.  All chimpanzee groups live in highly social groups, and antisocial behaviour would be detrimental to prolonged group cohesion.  In fact, wild behavioural studies have shown that chimpanzees do have a tendency to distribute various foods equally among kin (e.g., Pruetz & Lindshield, 2011).  Western chimpanzees in Senegal have been observed to share plant food, honey, meat, and tools based on elaborate hierarchies that have yet to be fully understood.

In the future more wild behavioural research may need to be conducted to better understand how sharing behaviours function with a chimpanzee community, and how their sense of fairness relates to our human sense of fairness.  So although we do not have all the answers yet, it seems likely that our common ancestor with chimpanzees had a similar sense of fairness in regards to resource allocation.  And we should feel lucky that that is the case because that means our sense of fairness is a deeply ingrained aspect of what it means to be fair.

You might want to follow Cadell Last on Twitter.

References:

Kaiser, I., et al.  2012.  Theft in an ultimatum game: chimpanzees and bonobos are insensitive to unfairness.  Biology Letters, DOI: 10.1098/rsbl.2012.0519

Proctor, D & de Waal, F..  2013.  Gambling and Decision-Making Among Primates: The Primate Gambling Task.  Proceedings of the National Academy of Sciences.

Pruetz, J.D. & Lindshield, S.  2011.  Plant-food and tool transfer among savanna chimpanzees at Fongoli, Senegal.  Primates, DOI: 10.1007/s10329-011-0287-x

A New Era

Last year I had a chance to visit the Fauna Foundation, a sanctuary in Montreal for chimpanzees “retired” from research laboratories and entertainment.  The Fauna Foundation received a lot of press after writer Andrew Westoll wrote The Chimps of Fauna Sanctuary, which is an account of his time as a volunteer at the sanctuary (I recommend reading it!).  This sanctuary serves an important function because they offer peace and relative freedom to chimpanzees that have only known a caged existence as test subjects in biomedical facilities.  As an outspoken critic of this research, I am enormously grateful for these sanctuaries.  In biomedical facilities chimpanzees often live in unsanitary conditions, without areas for foraging, or an ability to interact with other members of their own species.  Many chimpanzees that are eventually transferred to sanctuaries suffer from post-traumatic stress syndrome.

That is why I was very happy to hear yesterday that the United States would be largely phasing out biomedical research on chimpanzees.  The U.S. is the only country that still keeps chimpanzees for this type of research.  Austria, New Zealand, the Netherlands the United Kingdom introduced bans on using chimpanzees for biomedical research in 2006.  This is not just because using chimpanzees as guinea pigs is morally abhorrent.  It is also because chimpanzees as models offer us nothing that can’t be gained from using other animals as models (e.g., rats, hamsters, guinea pigs).  Considering that it is cheaper, more efficient, and useful to use rodents in biomedical research, there is really no reason to continue large-scale research on our closest relatives.

The United States new proposed federal rules wouldn’t limit all research, but it does place a stranglehold on new research.  Here is the statement from Working Group on the National Institutes of Health (NIH) website:

“NIH will not fund any new or other competing projects (renewal and revisions) for research involving chimpanzees and will not allow any new projects to go forward with NIH-owned or supported chimpanzees.”

Of the 451 chimpanzees currently being used by the NIH, 50 of them will be kept for scientists seeking to develop a vaccine for hepatitis C.  However, it is unknown how the 401 retired chimps will be funded or where they will go.  Some have already been transferred to Chimp Haven in Louisiana, but this sanctuary does not have enough space or funding for all of the chimpanzees.  Congress will need to make a decision in 2013 about where to get the 20,000 a year required for the care each chimpanzee.

Although these are fantastic developments, we still need to make sure that all organizations involved follow through on their promise to phase out biomedical research on chimpanzees completely.  As the final report by Working Group states: “[animal] models will continually raise the scientific bar for justifying the use of chimpanzees.”  Just because chimpanzee share 98% of our genome does not mean they are ideal candidates for vaccine development.  Eventually, the United States should push for a final complete ban on this research, as has already been done by the countries mentioned above.

However, I would take this one step further.  As amazing as sanctuaries like Chimp Haven and the Fauna Foundation are, they are only temporary solutions to a greater problem: chimpanzees in North America.  Chimpanzees evolved to live in rainforests and savanna in sub-Saharan Africa.  They do not belong on this continent.  In the future, I hope that once biomedical lab research on chimpanzees is completely in our past, we can work towards a transition from North American to African sanctuaries.

In African sanctuaries, chimpanzees can be offered the ability to enjoy the outdoors year round, which is something they cannot enjoy in North America.  Also, once in Africa, we can work towards reintegrating future generations into wild populations.  As I have written about before, genetic analysis now gives us the ability to identify the populations that chimpanzees originate from.  This would be useful for both the personal lives of the chimpanzees themselves, and for the long-term health and survival of chimpanzees in the wild.

Chimpanzees in biomedical labs, and chimpanzees in North America more broadly, are the product and extension of a colonial infrastructure.  They were stolen from their homes in the wild for entertainment purposes in zoos, theme parks, and the circus.  Throughout the 20th century, many scientists deprived chimpanzees of a real existence.  We must learn from what Jane Goodall taught us: these animals have a concept of self; they have feelings and emotions that are as real and deep as any humans.  She has been a constantly outspoken critic of what our system has done to our family:

“If we do not do something to help these creatures, we make a mockery of the whole concept of justice.”

— Jane Goodall

I suppose that is why my happiness today is still only a partial happiness.  It is a big victory, and perhaps a new era, for those that care about chimpanzees.  However, more work needs to be done.  In the 21st century, I hope that we can undo the wrongs of the 20th century.

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21st Century Neanderthals

A few months ago I pondered what it would have been like if other species within the genus Homo had survived into contemporary times.  Over the past 100,000 years, several members of within our genus became evolutionary dead ends as a result of our global conquest.  I proposed that we should view these past events as “fortunate extinctions.”

Why?

Well, our species has a long and disturbing history of cultural, ethnic, and racial conflict.  Throughout history we were barely able to tolerate different groups within our species.  What would modern era war mongers like Napoleon, Hitler, Stalin, Pol Pot, or Mao have thought of sharing this planet with another species?

My guess is that they wouldn’t have thought very highly of them.

That is why a part of me cringed when I heard that Harvard geneticist and synthetic biology pioneer George Church said he was close to bringing a Neanderthal into the 21st century (cue the redundant media coverage).

Here is Church’s explanation of how it could be done:

“The first thing you have to do is to sequence the Neanderthal genome, and that has actually been done. The next step would be to chop this genome up into, say, 10,000 chunks and then synthesize these. Finally, you would introduce these chunks into a human stem cell. If we do that often enough, then we would generate a stem cell line that would get closer and closer to the corresponding sequence of the Neanderthal. We developed the semi-automated procedure required to do that in my lab. Finally, we assemble all the chunks in a human stem cell, which would enable you to finally create a Neanderthal clone. ”

— George Church

After the media’s reaction to these statements, Church was quick to emphasize that he is not looking for an “adventurous female” to carry a Neanderthal: “I’m certainly not advocating it. I’m saying, if it is technically possible someday, we need to start talking about it today.”

There has been little insightful analysis and discussion about what bringing a Neanderthal into the modern world would mean for our species. Until now, Neanderthals have been the object of evolutionary anthropological inquiry and the creations of science fiction writers. Can they actually be members of our human-machine civilization?

According to Church, Neanderthals would be welcomed and would be good for society because they would increase diversity. I’m all for diversity, and I believe we can prevent people from ‘othering’ through education, but I really don’t think we are ready to live in a multi-intelligent species world.

I am open-minded enough to admit that I could be wrong on this one. I may even be in the minority. I’m sure lots of people love the idea of sharing this world with Neanderthals. And maybe Church is right and Neanderthals would offer us a new perspective and a new way to see the world that will benefit our species. But if history is any indication, there is a good chance that conflict would win the day. Of course, tolerance of difference is measurably increasing throughout the world. Stephen Pinker eloquently explained this in his recent book The Better Angels of Our Nature. However, religious bigotry, homophobia, and racial and ethnic tension are still major issues throughout the world. How would most people treat another species? And would Neanderthals struggle to find an identity in a world dominated by Homo sapiens?

These are important questions to ponder.

As anyone who regularly reads The Ratchet knows, this perspective is not coming from a luddite. I believe technology is going to dramatically change what it means to be human this century. Synthetic biology will be a part of this revolution (I have Church’s new book and I am ready to learn more about what role it will play in my life this century). I don’t think we should fear or prevent technological progress (I did request to join Svbtle after all!). I just think we should learn from history and make a prudent, well-informed decision before we bring the Palaeolithic into the Anthropocene.  If Dr. Church is looking for thoughtful discussion regarding this issue, this is my two cents.

You might want to follow Cadell Last on Twitter.

Also posted via Svbtle:

 

Universality of Preadaptation for the Human Condition

Originally posted on  the Scientific American Guest Blog (16/01/13)

I have often wondered about whether key human adaptations (e.g., bipedalism, large brain size, opposable thumbs) represented universal traits for the development of high intelligence and technological complexity.  In (2012) by evolutionary biologist Edward O. Wilson, he posits that they are.  Wilson argues that highly intelligent, technologically complex species have been so rare in the history of life because there are specific universal preadaptations required to produce the human condition.  He contends that without these preadaptations, a species intelligent enough to “build a microscope, deduce the oxidative chemistry of photosynthesis, or photograph the moons of Saturn” is an impossibility (Wilson, 2012: 45).  From Wilson himself:

“Overall, it now seems possible to draw a reasonably good explanation of why the human condition is a singularity, why the likes of it has occurred only once and took so long in coming. The reason is simply the extreme improbability of the preadaptations necessary for it to occur at all. Each of these evolutionary steps has been a full-blown adaptation in its own right. Each has required a particular sequence of one or more preadaptations that occurred previously. Homo sapiens is the only species of large mammal – thus large enough to evolve a human-sized brain – to have made every one of the required lucky turns in the evolutionary maze.”

— Wilson, 2012: 45

So what are these “lucky turns”?  And are they as universal as Wilson supposes?  First I think it is appropriate to explain what is meant be an “evolutionary maze.” An evolutionary maze is a metaphor to understand the probability of an organism acquiring a certain trait (i.e. large size, flight, echolocation, intelligence, etc.).  By using this metaphor we can say with certainty that descendants of contemporary pigs could become aquatic, but will never be able to fly.  This is because their ancestors acquired adaptations that “closed the door” to flight as a future adaptation through the evolutionary maze.  In essence, Wilson uses this metaphor to illustrate how many, and what type, of preadaptations it took for evolution to produce a highly intelligent, technologically complex species.  So that brings us back to “lucky turns”. What were they for us?  And can we deduce that these preadaptations represent a universal process for biological evolution?  Is the human condition a singularity?  According to Wilson there were four major turns, and these turns can be seen as prerequisites for biological evolution to produce another species with our abilities:

1. Land

The first of Wilson’s lucky turns is an adaptation to a terrestrial environment.  This is the first key preadaptation because Wilson argues that technological evolution past simple stone tools requires fire.  This means that in the evolutionary maze aquatic species could develop technology, but could never develop technologies with evolutionary trajectories of their own.  Therefore, no descendant of the octopus or dolphin could deduce oxidative chemistry of photosynthesis, or photograph the moons of Saturn, without first adapting to land.

2. Large body size

Wilson’s next preadaptation is large body size.  The reason for this adaptation is fairly self-explanatory: in order for a species to develop human-level intelligence, they must have a body that can support the evolution of a human-sized brain.  Wilson draws on his experience studying the highly complex societies of ants, bees, and termites to support the inclusion of this preadaptation: “[body size is the] one reason why leafcutter ants, although the most complex of any species other than humans, and even though they practice agriculture in air-conditioned cities of their own instinctual devising, have made no significant further advance during the twenty million years of their existence.” (Wilson, 2012: 46).  In contrast, we acquired this adaptation gradually over time within the order primates.

3. Grasping hands

The third preadaptation is grasping hands.  For Wilson, a species that has not acquired this ability will never be able to manipulate the environment in the way necessary to produce complex technologies.  Of course, this is a preadaptation that our lineage acquired within the order primates.  Grasping hands distinguishes primates from all other mammals.

4. Meat/Control of Fire

The fourth preadaptations are the consumption of meat and control of fire.  Meat is a necessary adaptation for Wilson because it yields higher energy per gram eaten, and because of the cooperation between individuals required to acquire meat.  In our lineage, meat was first consumed regularly within the genus Homo.  Before this the australopithecines subsisted off of vegetation, although they were potential scavengers as well.  Regular consumption of meat was followed shortly by the control of fire.  For humans, control of fire allowed us to catch larger game, and created a central common cooking space, which facilitated the development of an even more complex social environment dependent on altruistic sharing of resources.

The Evolutionary Maze

The metaphor of the evolutionary maze is a useful one.  It can help us conceptualize biological evolution.  However, Wilson depicts the human journey through the maze to be the only possible way for biological evolution to produce both high intelligence and technologically complex species.  Of course, I agree that the maze towards these evolutionary developments is narrower than the maze towards less complex adaptations.  I also agree that a great number of preadaptations are necessary for a species to achieve high intelligence and technological complexity.  However, the human condition may not be a singularity.  Unfortunately, we know of only one species that has developed high intelligence and technology with an evolutionary trajectory of its own.  Therefore, our sample size is too small to be definitively sure that our path through the maze was the only one.

As a consequence, I believe questions about the universality of the human condition must be relegated to a grey borderland between philosophy and empirical science.  Are there universal preadaptations?  I think it is possible, but we can’t scientifically determine that yet.  Take for example Wilson’s first preadaptation: adaptation to land.  Is it impossible for a lineage adapted to an aquatic setting to develop high intelligence and technological complexity?  I am just not sure how we can scientifically rule that out.  Just because it hasn’t happened on Earth, doesn’t mean that it can’t happen in the future, or on some other planet similar to our own.

As Wilson point out in the book, alien scientists studying our planet three million years ago would likely think nothing special of the australopithecines.  However, they were part of the maze that ended up producing us.  Could our species be making a similar mistake as Wilson’s hypothetical alien scientists if we conclude that the evolutionary maze to high intelligence and technological complexity is shut to the descendants of octopuses and dolphins?  Furthermore, we can’t conclude that consumption of meat and control of fire are necessary preadaptations, even though they were for us.  Although meat yields higher energy per gram eaten when compared to vegetation on Earth, it may not be the case on other planets.  I would argue the same with the preadaptation for control of fire.  It was important for our lineage, but could technology develop without control of it in an aquatic setting?  We don’t have the data to rule it out.

On the other hand, I believe the preadaptations Wilson explored do give us important insight.  For example, I would think it to be highly unlikely for a species with a small body size to develop human-level intelligence.  As he mentioned, the lack of advance among the social insects is likely attributable to this variable.  Also, I am in general agreement with Wilson that a species like us would require some type of grasping preadaptation.  Of course, grasping hands could be supplemented for the evolution of some other type of appendage (e.g., fin, tentacle, etc.) that could be used to manipulate the external environment.

This means all intelligent science fiction aliens should be equipped with some type of grasping appendage, in order to be scientifically appropriate.  Jokes aside, this type of question is worth exploring.  However, I think we should be cautious and hesitant to make any broad conclusions.  A scientific consensus will not likely be reached until we have more data, and that requires understanding life off of our island of life: Earth.

You might want to follow Cadell Last on Twitter.

References

Wilson, E.O.  2012.  The Social Conquest of Earth.  New York: W.W. Norton.