Is English a Virus from Outer Space?

Last week, I attended talks for the Society of Anthropology of Paris meeting here in Montpellier. This has been an interesting experience for many reasons. For one, the talks have shown some interesting differences in the politics of anthropology in France compared to the United States.

The society was founded by Paul Broca in May, 1859, six months before Darwin published the Origin of Species. Broca discovered the language-associated area of the brain that bears his name, and was the one of the first to study the Cro-Magnon fossils, discovered in France in 1868.

While the society carries the general name of Anthropology, it now focuses on Biological Anthropology. The talks were mainly what in America we would call archaeology: analysis of bones and food residues from historic and prehistoric graves and occupation sites. Interesting stuff, but a bit narrow in scope. Few talks focused on human behavior, apart from a session of evolutionary psychology talks Thursday morning. In contrast to the American Physical Anthropology meetings, there were no talks on nonhuman primates. Most strikingly, there was no sociocultural anthropology at all; they have different meetings. Apparently, the divide between quantitative, evolutionary anthropology and qualitative, interpretive anthropology is even more stark in France than in the US. It seems more like an old, nearly-forgotten divorce than the uncomfortable marriage-on-the-verge-of-separation that still exists in American anthropology.

Another interesting aspect of the meetings was the use of language. The audience was mainly French, so I expected all the talks and slides to be in French. One speaker, based in England but not a native English speaker, gave her talk in English, but most of the language on her slides was French. The other speakers spoke in French, but for many of the talks, some or even all of the slides were in English. They frequently used English for technical terms, or when citing the title or findings from papers published in English. This was all very typical of what I have been seeing in departmental seminars at the University of Montpellier. The audience is mainly French, and most of the talks are in French, but visiting speakers usually give their talks in English, which everyone in the audience seems to understand reasonably well. And even when the speakers are French, their slides are sometimes entirely in English.

Before coming here, I had the impression that the French were highly protective of their language. They have laws requiring the use of French in commercial communications. They have L’Académie française, which tries to keep the language contaminated from foreign words like “le sandwich” and “les airbags.”  Government agencies strive to come up with replacements for English words like “buzz,” “chat,” and “newsletter.” And in a recent study, France ranked right at the bottom of the heap of European countries for English language proficiency. And there’s a stereotype that the French are hostile towards people who can’t speak French properly (meaning most of us Americans).

In contrast to what I expected, though, most of the people I’ve encountered seem to have a very positive attitude towards English. People who know some English are eager to practice it. It’s not like northern Europe, where almost everyone in the cities seems to speak perfect English, but enough people speak English that in many situations, I have to make an effort to keep using French. The books in the lab library are mainly in English. My French colleagues read and publish their papers in English-language journals. Lab meetings and social interactions are mainly in French, but everyone can switch to English when needed (like when I give up in my struggle to explain something in French, which often happens). Outside of academia, English words and phrases occur in ads and on signs, and English-language songs dominate the radio (which is required by law to have 40% of songs in French during prime hours).

On a global scale, French has fallen dramatically from its 19th Century peak as a major language of empire, diplomacy, learning and culture. The percentage of American and British students studying French as a foreign language has dropped dramatically in recent decades. In much of North America, place names from Indiana (La Fontaine) to Minnesota (the redundantly named Mille Lacs Lake) reflect a long-lost empire, where French has been reduced to a declining minority language in Louisiana and even in Canada, where the proportion of native French speakers has dropped to 22% of the population. Even in Africa, where France had a vast colonial empire, French may be losing ground compared to other languages. In formerly French North Africa, Arabic competes with French for status as the primary language. South of the Sahara, French is still widely used as an official language, but Rwanda dropped French in favor of English, both in protest to French actions during the Rwandan genocide, and as part of an effort to build closer ties to the Anglophone East African Community. English is an official language of Africa’s most populous country (Nigeria) and the biggest economy (South Africa), and is the language of higher education in Africa’s second most populous country, Ethiopia, even though Ethiopia was never part of the British Empire. In Asia, English is widely spoken in South and Southeast Asia, including the second most populous country on the planet, India, whereas French has a small and declining number of speakers in former French Indochina.

In the thousand year-old rivalry between English and French, English seems to be gaining the upper hand.

Which has me wondering: what makes a language expand or contract? Does it mainly have to do with features outside the language, such as politics, demography, military conquest, and migration? Or does it also depend, at least to some extent, on features of the language itself?

I remember a night more than twenty years ago, during my first field season in Africa, studying baboons in Kenya. Gathered around the dinner table with American and Kenyan researchers, eating by the warm glow of kerosene lanterns, conversation turned to why English was so widely spoken. One of my American colleagues suggested that it was because English was so open to new words and ideas. Instead of trying to keep out foreign words, English readily adopts new words, like America adopts new immigrants.

I thought this was a funny thing to be saying in Kenya, where English was widely spoken not because the language is so open and friendly, but because it was the language of the British Empire, which colonized Kenya and much of the rest of Africa, as well as most of North America. The reason Kenyans and Americans had English as a common language had more to do with British seafaring, commerce, and military might than with any particular virtues of the language they spoke.

Similarly, all sorts of languages that might be hard for non-native speakers to learn have spread widely due to non-linguistic factors, such as the military might and demographic growth of their speakers. English speakers generally consider Russian, Chinese, and Arabic all hard to learn, but that didn’t stop these languages from spreading widely as their respective empires expanded.

All the same, thinking more about language from a Darwinian perspective makes me wonder whether, in the competition among languages, languages might change in ways that affect their relative competitive ability.

A language, like a biological species, has a life cycle, and is in competition with other languages. A language may spread widely and diversify, leaving numerous descendant languages, as Latin gave rise to the Romance languages, or Sanskrit to many modern Indian languages. Or it may shrink and die.

Growth or decline for languages occurs much the same way as it does for species: through births, deaths, and migration. Each time a child is born and learns her mother tongue, a new speaker is added to the language. If a language is no longer being transmitted to the young, but is only spoken by old people, the language will die with the last aging speakers.

Languages also migrate with their speakers. One reason English is spoken so widely is because seafaring English speakers established colonies around the world. In some of these colonies, English speakers became numerous and eventually swamped not only the native populations but also all subsequent immigrants. Some linguists call America a “language graveyard” because speakers of so many different languages come to America, only to have their children learn English and forget their mother tongue.

The total population of French speakers appears to be growing. In evolution, though, what really matters is relative growth rate. Genetic fitness, for example, is essentially a measure of relative growth rate of particular variants of genes (“alleles”) in a population. Alleles that have a high relative growth rate become increasingly common in the population, and may eventually reach fixation, present in essentially all members of the population. An allele, or a language, can become less common in the population if it is increasing at a slower rate than the population as a whole.

But unlike genes, language isn’t transmitted only from parents to offspring. Language can also be transmitted to completely unrelated people. In this way, a particular language is more like an infection.

As William S. Burroughs wrote and Laurie Anderson sang, “language is a virus from outer space.”

This is a thought-provoking image. Like a virus, a particular language is not part of the host’s own genome, but it uses the host to spread itself. However, it is wrong on two counts.

First, even though human language is an extremely peculiar and probably unique form of communication among earth species, invoking space aliens as an explanation is sort of the reverse of Occam’s razor: “among competing hypotheses, the hypothesis with the fewest assumptions should be selected.”

Second, even though language has some virus-like properties (it is can be transmitted from one person to another), it is really more like a plasmid than a virus.

Viruses are parasites that hijack the cellular machinery of other organisms to make more copies of themselves. But they usually don’t do anything to help the host, and in fact they often harm the host. A cold virus has been making the rounds of my family, and it has done nothing good for any of us. Instead, it lurks in our cells, churning out more copies of itself, and manipulates our bodies to ooze those copies out into the world to be spread to other people through coughing, sneezing, and running noses.

In contrast, at least as far as transmission is concerned, a language is more like a plasmid than a virus. Plasmids are little circular bits of DNA found in the cells of bacteria and other organisms.

http://en.wikipedia.org/wiki/Plasmid
http://en.wikipedia.org/wiki/Plasmid

Plasmids encode genes that provide handy tricks for the host, such as resistance to an antibiotic, or the ability to make a toxin. Plasmids can enable their hosts to live in what would otherwise be a hostile environment. Plasmids are useful to the host, rather than harmful, probably because of their mode of transmission: they can only be transmitted when the host reproduces (by dividing, in the case of bacteria) or when the host connects to another cell specifically to obtain new genes.

http://en.wikipedia.org/wiki/File:Conjugation.svg
http://en.wikipedia.org/wiki/File:Conjugation.svg

Like a plasmid, a language can do all sorts of useful things for its host. So much so that I’ve been making considerable effort to infect myself with a new one (French).  The infection is far from complete (and is progressing rather more slowly than I might have hoped), but it’s far enough along that I can do a number of useful things with it, like order coffee and chocolate croissants, or renew my commuter rail pass, or get a new inner tube for the wheel of my jogging stroller, all of which would be harder to do using only the infection that I inherited (English).

The idea of language as a virus, or plasmid, or other transmissible agent is closely related to the term “meme,” which Richard Dawkins coined in The Selfish Gene, to make an analogy between cultural and biological evolution. The word has caught on, happily, to refer to Internet pictures of LOLcats and such, which are memes in exactly the sense that Dawkins originally meant: little bits of information that are able to get themselves propagated, and which undergo mutations and evolve overtime in branching lineages, just as genes do. In this sense, a language is basically a big complex of memes.

In this view, the individual words in a language are memes. Like genes, they evolve, becoming more or less frequent in a population over time, and undergoing mutations, and sometimes becoming extinct.  Words compete with other words in the meme-pool.

The word computer, for example, is a Latinate word that came into English from French around 1646. At that time, the word “computer” referred to a person, not a machine: someone whose job it was to do calculations. Three hundred years later, when electronic calculating machines were invented, English speakers described the machines as “computers.” This sense of the word spread from English into a number of other languages, like Russian (kompyuter) and Swahili (kompyuta). But in France, the original home of the term “computer,” they instead use “ordinateur,” a word created in 1955 at the bequest of IBM France, because the term “computer” seemed “too restrictive in regard to the possibilities of these machines.”

So while languages have memes like viruses have genes, and like viruses they can be transmitted from one person to another, languages are usually useful to their host, rather than harmful. Why is that the case?

One reason might be the mode of transmission. A virus that is transmitted via saliva and snot is mainly interested in making its host produce lots of saliva and snot, and sneezing and smearing those fluids as widely as possible. The virus doesn’t share any genes in common with the host, and its reproductive success doesn’t depend on the reproductive success of the host. (Except for sexually transmitted viruses; though here, the interests of the host and virus still diverge, since the host doesn’t necessarily reproduce each time it has sex. A sexually transmitted virus benefits if the host lives long enough to keep having sex with more partners, but its own success doesn’t depend on whether the host actually reproduces successfully.)

In contrast, the surest means of language transmission is through the reproduction of the speaker. Languages take a long time to acquire (as I am painfully aware), and even though people say little kids learn languages quickly, it still takes years from them to learn their mother tongue properly, and from what I’ve seen in my own family, acquiring a new language is no trivial matter even when young. Because transmitting language from parent to child depends on successful raising of the child,  the interests of the language closely coincide with the interests of the host.

But unlike a host’s own genome, a language can be transmitted horizontally as well as vertically: from host to host, rather than just host to offspring. It is in this respect that a language is more like a plasmid than either a virus. Like a plasmid, a language is useful to its host, it is transmitted to the host’s offspring, and it can also be transmitted to other unrelated hosts.

Of course, languages aren’t exactly like plasmids. It’s just an analogy, and any analogy can be pushed too far. But to me it seems a helpful analogy for thinking about the relative growth rates of different languages.

In an environment full of a particular antibiotic, such as penicillin, bacteria that acquire the penicillin-resistance plasmid will survive and reproduce, whereas bacteria without that plasmid will die out.

Likewise, in a world where English provides access to information, jobs, and money, people will have a strong incentive to acquire English.

On balance, I would guess that most of the reasons for the success of English have little to do with any particular properties of English. English is not, of course, intrinsically a “better” language than French, or Swahili, or Basque, or any other language. All of these languages can be used to communicate any idea. Most of the current advantages of English have to do with the social and political environment, which depends more on the happenstance of the British Empire spreading English across the world and planting colonies in fertile places, and the resulting the wealth and power of the United States and its impacts on global commerce, popular culture, science and technology. Currently a huge factor must be frequency dependent selection. As English becomes more widely spoken, it becomes increasingly advantageous to know it. This produces a snowball effect, benefiting English at the expense of other languages.

Still, are there some linguistic features that have helped English become widespread? Has English itself evolved in ways that make it more contagious? Perhaps the early history of contact with other languages, like Brythonic, Old Norse, and Norman French, helped to eliminate some features that were harder for non-native speakers to learn (most aspects of gender and case, for example). Elimination of tricky features seems to have happened with other languages. Swahili, for example, emerged as a trading language between Africans speaking Bantu languages and traders from Arabia, Persia and elsewhere. Many Bantu languages related to Swahili have tones, but Swahili doesn’t, perhaps as a result of interaction with Arabic and other languages.

Perhaps the combination of Germanic grammar and Romance vocabulary helps to make English easier for speakers of these two major branches of European languages to learn.

And also, given that much of the innovation in science, technology, and other ideas happens in Anglophone countries, and is communicated in Anglophone channels, English is rich in vocabulary useful for talking about these new things and ideas.

But another way that English might help propagate itself is through the production of little bits of language that are highly infections in their own right: songs, books, movies, and the like.

Popular music, and music videos, seem especially virus-like. A pop song doesn’t provide obvious benefits to the listener. Instead, it exploits the listener’s sensory biases in ways that make the listener want to repeat the experience.

Take the music video for Gangnam Style, for example. I watched it many times.  I haven’t learned anything useful from it, except perhaps an explanation for why all the kids at the disco are dancing like they are riding ponies. This mainly Korean language video went viral, in part due to its catchy little hook of weird English.

In the book Plagues and Peoples, historian William H. McNeil argued that a key factor in history was the diseases carried by different peoples. The Eurasian landmass provided a massive Darwinian breeding ground for particularly nasty infectious agents, passed from domestic animals to people, and transmitted over thousands of miles of steppe by mobile horsemen. When Europeans first traveled to the Americas, they carried these highly infectious agents with them, with disastrous results for the Native Americans.

In a similar way, the vast Anglophone world serves as a global breeding ground for particularly infectious memes. I’ve talked with people who say they learned their English from listening to rap, or watching TV.

Perhaps official efforts to protect French actually serve to weaken the language, reducing its ability to resist infection, and reducing pressure on the producers of songs, books, movies and other cultural artifacts to be maximally infectious.

 

 

Green Porno and Disgust

Isabella Rossellini is doing a show, Green Porno, in which she performs the mating behavior of a whole range of other species, such as honey bees and spiders. The show is based on a series of videos that she has been making since 2008.

Isabella Rossellini and friend.
Isabella Rossellini and friend.

Holy cow. These are awesome – and biologically accurate, in a whimsical, funny way. Rossellini clearly did her homework. But sexy? Not so much, I think. Rossellini herself says that though the bits are called “Green Porno,” “There is nothing porno about them.”

I teach a course on Sex, Evolution and Behavior, in which I occasionally illustrate key points with short video clips of the mating behavior of other species, from slugs to albatrosses. Not for titillation, mind you, but for education. In fact, while such video clips may be weird, or interesting, or comical, or gross, or some combination of these, they are pretty much never even remotely titillating. At least in my opinion. And my impression is that for most people, sex in other species is generally much more icky than sexy.

Which makes me wonder: why might this be the case?

The world is big, and has many kinds of people in it, and perhaps somewhere on the Internet there are sites for people who really do find the mating behavior of lobsters arousing. But I expect those sites are vastly outnumbered by sites depicting the mating behavior of our own species.

So why do we perceive sex in other species to be disgusting rather than sexy?

One possible explanation is that this disgust response is part of an evolved psychological mechanism that promotes mating decisions that enhance, rather than reduce, fitness. If we found slug sex really sexy, rather than disgusting, we might try mating with slugs, which (among other things) would be a real waste of mating effort.

If this hypothesis is right, that disgust at other species’ sexuality is a reproductive isolating mechanism, an adaptation to keep us from mating with the wrong species, then we should find the sexuality of species closely related to us to be particularly disgusting. After all, we probably couldn’t really mate with a slug even if we wanted to, but mating with something more closely related to us, like a chimpanzee, at least seems within the realm of possibility.

Back when the world had multiple species of humans living at the same time, such as our ancestors and the Neanderthals, interspecies mating would have been a real option. And studies of fossils and ancient DNA indicate that such matings did occur, at least on occasion. Given that hybrids can have various genetic problems, such as infertility, individuals are likely to have more offspring if they reliably mate with their own species, rather than some other species. And indeed, many aspects of animal behavior and anatomy appear to be related to species isolating mechanisms: courtship behavior, species-specific coloration patterns, and genitalia designed to fit like a lock and key, so that the parts only fit with the right partner.

So, what about this prediction, that if disgust is a reproductive isolating mechanism, we should find the sex of species closely related to us to be particularly disgusting? I don’t know of any formal studies of this, but from watching and listening to people’s reactions to monkeys at zoos, I get the strong impression that in general, people really do find monkey sex disgusting, as well as funny and embarrassing.

As a primatologist, I have seen lots of monkey sex: baboons, rhesus monkeys, chimpanzees, gelada monkeys, and so on. All these animals have sex in the open, in public, for everyone to see, so you don’t need to be a creeping pervert to see them going at it. In many cases, you would have to make a real effort to avoid it. And none of it, really, is very sexy, from a human point of view. In chimpanzees, mating is a furtive event that lasts six or seven seconds on average, which often ends with the female screaming and darting away from the male, as if she is terrified that he might beat her up. Which he might well do.

In my first field season as a primatologist, studying baboons in Kenya, I spent quite a bit of time looking at baboon bottoms. Not because I am particularly interested in baboon bottoms, but because (1) if you are following baboons, you’re going to see a lot of baboon bottoms, just that’s what you see when they’re walking in front of you, and (2) baboon bottoms display a whole lot of really valuable information about their reproductive state. You can tell whether a baboon is male or female, for example, just by looking at their bottom, even if they are just little kids. Baboons have a region of bare, tough skin going across their top of their bottoms that serves as a seating pad: the ischial callosities.

Males have a continuous seat pad surrounded by a patch of grey skin:

Back side of a male baboon
Back side of a male baboon

 

 

 

 

 

 

 

 

Whereas females have two separate pads, for the left and right cheeks, separated by the genital opening:

Female baboon at Gombe with bright red pregnancy sign.
Female baboon at Gombe with bright red pregnancy sign.

 

 

 

 

 

 

You can tell where a female is in her ovulatory cycle, as when a female is approaching her fertile time, the skin of her perineum swells up into a big pink sexual swelling, which looks extremely uncomfortable. And if a female is pregnant, the bare skin above her ischial callosities turns from grey to bright crimson.

When I was first habituating baboons (following them at a distance so they would get used to us and let us observe them at closer range), one afternoon we managed to get close enough to our group to see them resting on the face of the steep cliff where they would spend the night. Peering through my binoculars, I could see one female with what appeared to be a raw, festering sore by the base of her tail. As the weeks went by and the baboons let us get closer, I realized that this “sore” was just the bloody red pregnancy sign. It doesn’t look nearly so nasty when you are close enough to see that is not in fact a festering sore.

So during my ten months of following baboons around, I spent a lot of time looking at their bottoms, drawing pictures of their bottoms, taking notes of their bottoms to learn who was who and what their reproductive state was. At first, some features of baboon bottoms seemed kind of gross. I got used to that. And eventually I learned what sort of bottoms looked especially appealing to male baboons, by seeing who made special efforts to mate with.

Ahabazi grooming Ubergiji, who has a full sexual swelling.
Ahabazi grooming Ubergiji, who has a full sexual swelling.

 

 

 

 

 

 

But never in my loneliest days in the field did I find baboon bottoms sexy. Sorry babs, that just how it is.

On the other hand, many examples of hybrids exist. For example, as Kate Detwiler has documented, blue monkeys and redtail monkeys at Gombe and several other sites mate and produce hybrid offspring. My first experience studying primates involved a class project looking at the behavior of the hybrid offspring of a sooty mangabey and a mandrill: a mangadrill. So if disgust is part of a reproductive isolation mechanism, it clearly doesn’t always work.

Whether or not disgust is a reproductive isolating mechanism, it certainly plays a big role in regulating sexual behavior. Even within our own species, we perceive many categories of mating behavior as well, kind of gross. Or really gross. Little kids often seem to think that even kissing is pretty gross, much less the other things that grown-ups are rumored to do in private.

And much of the human disgust response makes sense from an evolutionary perspective. For example, various studies have found that women are considerably less interested in graphic depictions of mating than men are. Many men enjoy looking at graphic, impersonal depictions of anatomical function. Many women find that sort of thing disgusting. Instead, they prefer reading romance novels, or watching romantic movies, where sex occurs in the context of relationships developing between realistic characters. Or with vampires. Or werewolves. Whatever.

Is there a reproductive isolation mechanism at work here?
Is there a reproductive isolation mechanism at work here?

 

 

 

 

 

 

The emphasis is on the relationship first, anatomy second.

A recent example of this sex difference in action is the case of the politician Anthony Weiner, who sent pictures of his privates to women who were not his wife. One can imagine him thinking, “Hey, I’d love to have women send me naked pictures of themselves! Surely they would like me to do the same for them!” And maybe there are women who would like that. But I think this response by a blogger is more typical: “The truth is, guys, your ‘junk’ is one of the last things we want to see up close via digital or printed media.”

The Golden Rule, “Do unto others as you would have done unto you,” doesn’t work so well in cases where people have strong differences of opinion about what they would like to have done unto them.

And from an evolutionary perspective, this sex difference makes sense. If it is important to be choosy about mating, then being aroused by random sexual images would be counter-productive. In humans, women tend to be choosier than men. This makes sense, because men and women face much different costs from mating. A man who has sex with a random stranger might get the evolutionary “win” of impregnating her without having to do any work bringing up the baby. A woman who has sex with a random stranger may get stuck doing all the work. Thus for men, sex with strangers is an opportunity, whereas for women it is a risk, and best to be avoided. (Unless, for example, that stranger is so amazing that having his baby would be worth the trouble. Elvis, say, or Magic Johnson.) Disgust at random male junk may thus be an important mechanism guiding mating decisions that prove beneficial, at least on an evolutionary timescale.

Even for men, though, sex with strangers can be risky, if those strangers are infected with nasty diseases. So both sexes should be equally disgusted by anything that indicates such an infection, like festering sores.

In humans and certain other animals, including many bird species, sex often happens within a long-term relationship, rather than with random strangers. And just as in many birds and some mammals, like wolves, male humans do a lot of parental care. If a man has good reason to think his wife is mating only with him, and is uninterested in mating with other men, then he will have good reason to believe that her children are his, and that he should invest in them, by bringing them meat, or carrying them around, or changing their diapers, or whatever.

In contrast, among chimpanzees, males and females both mate promiscuously. Males don’t provide any parental care (apart from defending a group feeding territory), so females are always stuck doing all the work of parenting. However, males sometimes kill babies of females that they haven’t mated with. So females have a strong incentive to mate with all the males of her community, to convince them all that they might be her baby’s daddy.

Given this difference in mating strategies, if female chimpanzees used smart phones, they might like nothing better than to receive photos of male chimpanzee private parts. I suppose that’s an experiment that could be done.

Recently, disgust has gotten lots of attention as one of the key moral emotions. In college, I sat in on J. Z. Smith’s Religion in Western Civilization class.   In talking about Leviticus, the Biblical book of rules, many of which seem baffling beyond belief, Smith argued that “the complaint of the writers of Leviticus was not, ‘God, why have you made me such a sinful being.’ No, it was more like, ‘Why have you made me with so many holes?’” Humans leak all sorts of disgusting substances from their various orifices, and many of the rules of Leviticus involve proper regulation of these fluids.

Smith seemed to think that these rules involved a fairly arbitrary sense of disgust, rooted more in aesthetics than reason. For example, he argued that Jewish dietary law forbade eating pork because pigs are disgusting animals. They wallow in filth, they eat trash, we shouldn’t incorporate such filthy animals into our bodies. Smith argued that the argument that such laws protected Jews from trichinosis was an invention of 19th century Reform Jews who wanted to find more rational foundations for traditional beliefs.

More recently, Paul Rozin and others have argued that rather than being arbitrary, disgust really is rooted in evolutionary logic: many things that we find disgusting are dangerous: rotting meat, maggots, festering sores, snot, feces and the like can all transmit pathogens. If we eat such things, or even touch them, they can make us sick, or dead. From an evolutionary perspective, it makes sense to have emotional mechanisms that make us avoid such potentially dangerous substances. In this view, feelings of disgust originally based in avoidance of pathogens have expanded to provide one of the main foundations of moral feeling.

A moral emotion like disgust can guide behavior more quickly, and more reliably, than rational arguments. If we had to stop to think and debate amongst ourselves whether rotting carcasses, for example, were safe to touch, we might pick them up and expose ourselves to all sorts of pathogens before we have persuaded ourselves that maybe that’s not such a good idea. The same way with many moral actions: if people think an immediate, gut response of disgust to pedophilia, or rape, or murder, they will be inhibited from even giving it a try.

Disgust seems to involve both learned and innate components, and develops gradually as children mature. Toddlers, for example, seem to find nothing disgusting. But pretty much everyone eventually grows up to find rotting meat and vomit disgusting. People seem to have a natural disposition to develop feelings of disgust towards things that carry a strong risk of infection.

More recently, Jonathan Haidt and others have argued that disgust is at the heart of the six moral foundations or dimensions: care/harm, fairness/cheating, liberty/oppression, loyalty/betrayal, authority/subversion, and sanctity/degradation. In this view, disgust is involved mainly in the sanctity/degradation dimension.

Much of the current political debate about gay marriage involves tension between these different moral foundations. People who emphasize the first three moral dimensions see gay marriage mainly in light of care (we shouldn’t cause emotional harm to people by denouncing their private life choices as sinful), fairness (it’s only fair that people who love each other should be allowed to marry), and liberty (people should be free to be who they are and love who they love). People who emphasize the other dimensions see gay marriage mainly as an issue of authority (scripture says it is wrong) and sanctity (heterosexual marriage is a sacrament; homosexual marriage is wrong). Thus, people on both sides of the debate are morally outraged by the arguments of people on the other side.

And from an evolutionary point of view, an aversion to same-sex mating seems to make a certain amount of sense: such mating doesn’t produce offspring. But it turns out that evolution is more complicated than that. For some species, homosexual mating is not a preference or orientation for a portion of the population; it’s obligatory. For example, New Mexico whiptail lizard reproduces parthenogenetically; the species has only females, and they are all virgins. Nonetheless, even though their eggs are not fertilized, females still have go through the motions of mating, with another female, in order to produce eggs. (Incidentally, this unusual mating system seems to be a result of the hybridization between two other lizard species.)

And even in species that have both males and females, homosexual behavior occurs in a wide range of species. Among Laysan albatrosses in Hawaii, for example, there appears to be a shortage of adult males. Raising a baby albatross takes a huge amount of work. Mom and dad have to take turns flying far away to get fish to feed baby, while the other parent stays with the nest. A single parent just can’t manage. As a result, many females pair with other females. They mate with males who are paired with other females, but nest and raise chicks together with their female life partner.

Rossellini says her Green Porno doesn’t have a political agenda. It is more about educating people about what the world is like for other species. But her videos do an excellent job of illustrating that in nature, sex involves an enormous range of diversity, from the exploding kamikaze penises of honeybees to the playful, anything goes sex of dolphins.

And learning more about the sex lives of other animals is useful for getting a broader perspective for the behavior of our own species, whatever we might personally find to be disgusting. Or not.

Frodo (30 June 1976 – 10 November 2013)

Several of my blog posts have featured Frodo, the iconic alpha male chimpanzee of Gombe National Park. Frodo also figures prominently in several of my research papers, given that he has been a major player in aggression at Gombe, both within his own community, and during attacks on the neighbors. I’m sorry to report that Frodo died on Sunday, 10 November 2013. Perhaps fittingly, given Frodo’s aggressive behavior in life, aggression seems to have contributed to his death. Necropsy revealed that he had a scarred scrotum and infected testis, probably due to what seems to have been a canine puncture wound received in August 2013. As ye sow, so shall ye reap. [Edit (23 May 2022): subsequent results from pathology indicated that Frodo died from renal failure, not from infection from his scrotal wound.]

Jane Goodall named Frodo for the noble, humble, diminutive hobbit from the Lord of the Rings, which she had been reading to her son. From a cute little baby chimpanzee, Frodo grew to be a hulking brute, a despotic alpha male, and a fearless hunter of monkeys.

Frodo was born on 30 June 1976, the second of Fifi’s nine offspring. Fifi was a highly successful mother and was for many years the highest-ranking female of Gombe’s Kasekela community. As an infant, Frodo proved mischievous, disrupting Jane Goodall’s efforts to record data on mother-infant relationships by grabbing at her notebooks and binoculars. As he grew older, Frodo developed a habit of throwing rocks, charging at, hitting, and knocking over human researchers and tourists. In 1988, Frodo grabbed and pulled at cartoonist Gary Larson’s arm when he visited Gombe, and the next year Frodo severely beat Goodall herself.

In his prime, Frodo weighed 55 kg (121 lbs), larger and stronger than any of his peers. Frodo rose quickly in the ranks as he matured and won the position of alpha male by overthrowing his brother Freud in October, 1997. Frodo reigned as alpha male for 5 years, until weakened by sickness in December 2002. We knew the game was up for Frodo when he gave submissive pant-grunts to the next alpha male, Sheldon, in January 2003.

As alpha male, Frodo ruled by brute force. Unlike his brother Freud, who frequently groomed lower ranking males in apparent efforts to win their support, Frodo rarely groomed any other males, but instead frequently presented himself to be groomed by them.

Frodo competed vigorously for mating opportunities throughout his life, fathering his first offspring, Zeus, when he was 17, and his last, Samwise, when he was 25. He even forced his attention on his own mother, fathering an infant, Fred, who lived for less than a year before dying in a mange epidemic. Frodo fathered both of Gremlin’s twins, Golden and Glitta, the only wild chimpanzee twins known to have survived to adulthood. Frodo’s son Titan follows in his father’s footsteps by throwing rocks at baboons, chimpanzees and people, and has recently challenged the current alpha male. In total, Frodo fathered eight offspring, more than any other male at Gombe but Wilkie (who fathered 10). Frodo’s offspring were born to six different females: Trezia, Patti, Gremlin, his own mother Fifi, Sparrow and her daughter Sandi.

After being deposed in 2003, Frodo spent months by himself recovering, and when he rejoined the other males he had fallen to low rank. He continued to show keen interest in competing for mates and hunting monkeys, but he mellowed considerably, and in his last years rarely showed any signs of aggression towards people.

Frodo was the first chimpanzee that I saw in Gombe, and I recognized him instantly, with his silvery grey back, the round ruff of silvery hair framing his face, and his large size. Frodo taught me what life is like for most chimpanzees: you must constantly be aware of where the alpha male is, because he might charge any time, and may beat you up. The first time he came charging past me, I wondered why everyone was running away; as a kid I had read George Schaller’s descriptions of gorillas, and how when they charged you must stand your ground, and only people who ran got bitten. I assumed the same must be true for chimps. And sure enough, when I studied chimpanzees for my dissertation research in Kibale Forest, Uganda, the alpha male Imoso would simply veer around me if I got in his way, acting as if that was what he meant to do. But not Frodo. He saw that I wasn’t moving and went straight at me, knocking me into the bushes. He beat on me briefly with his fists, but in a surprisingly gentle way. He could have easily done real damange, but he acted as if his only goal was to show me who was boss. Him.

My next day in the forest, I was extremely wary of Frodo. I managed to avoid him for most of the morning. However, during a hunt, someone else ended up with the carcass of a redtail monkey, and Frodo was angry. He charged around, displaying. He charged past a whole line of researchers to get to me, where he knocked me into the bushes yet again.

That was the last time that Frodo bothered me, though. He seemed to accept that I was part of the gang of people that followed him and his community all around the forest, and that I sufficiently acknowledged his magnificence.

Frodo resting on the trail in June, 2009.
Frodo resting on the trail in June, 2009.

Frodo was one of several F-family chimpanzees that rose to high status. Most of Fifi’s offspring that survived to maturity rose to high ranks, with three of them becoming alpha male: Frodo’s older brother Freud, Frodo himself, and the current alpha male, Ferdinand. Fifi’s daughter Flossi is one of the highest ranking females in the Mitumba community. Frodo is survived by four sons (Zeus, Titan, Tarzan, and Sindbad), three daughters (Golden, Glitta, and Samwise), his brothers Freud, Faustino, and Ferdinand, sisters Fanni, Flossi, Flirt at least two grandchildren, and numerous nephews and nieces.

Frodo grooming his daughter Glitter (June 2012).
Frodo grooming his daughter Glitter (June 2012).

Researchers and filmmakers followed Frodo throughout his life, making him one of the most thoroughly documented wild chimpanzees in history. Numerous books and scientific articles described Frodo’s success as a hunter, fighter, and alpha male. Frodo first appeared in films as an infant in People of the Forest: The Chimps of Gombe (1991, Discovery Channel). Frodo knocks presenter Charlotte Uhlenbroeck off her feet in The New Chimpanzees (1995, National Geographic). The films Fifi’s Boys (1996, BBC) and Chimpanzee Diary (1997, BBC) depict Frodo’s rising power and rivalry with Freud. Frodo dominated the giant screen feature Jane Goodall’s Wild Chimpanzees (2002, Imax), filmed at the peak of his powers. More recently, Frodo was featured in The Dark Side of Chimpanzees (2004, BBC), Return to Gombe (2004, Discovery Channel) and Chimpanzee Family Fortunes (BBC, 2006).

Gombe just won’t feel the same with Frodo gone.

La Vie en France

Currently I am on sabbatical in France, hosted in the lab of Michel Raymond at the University of Montpellier-2.

I have been working on papers on chimpanzees and aggression, but also trying to learn French, which has me thinking a lot about language, including the evolution of language, and parallels between biological evolution and linguistic evolution.

I didn’t study French in school, apart from a few weeks in grad school, but over the years have tried, in fits and starts, to learn the language on my own. I have studied two evolutionary cousins of French, Spanish and Italian, which both helps and hurts. There are lots of similarities in the vocabulary and grammar of these languages, but my wife complains that I speak French like a Spaniard.

Languages are like biological species, in that they change over time, and are related to other languages in a tree-like pattern. Just like humans and chimpanzees share a common ancestor that lived around 6 million years ago, French and English share a common Indo-European ancestor that was spoken something like five or six thousand years ago, before the Italic and Germanic branches of Indo-European diverged.

http://www.hartleyfamily.org.uk/IE_Language_Tree_by_Warnow.jpg
Indo-European Language Evolution

 

 

 

 

 

 

Words are a bit like genes, in that they are units of inheritance. A language is made up of words, much like a genome is made up of genes. Like genes, words change gradually over time, in their meaning and pronunciation. With written languages, we can track these changes with spelling, just as we can track genetic changes with differences in the letters of the genetic alphabet of base pairs (A, T, G and C).

Like our genes, we usually get our language from our parents. But unlike genes, we can also get bits and pieces of language, and even entire languages, from people who are completely unrelated to us.

Unlike animal species (but like some organisms, like bacteria), languages can “mate” freely and exchange words. Thus, English and French have been exchanging words freely over the past thousand years, even though they are from different branches of the Indo-European language family.

One of the fascinating (and sometimes frustrating!) things about French is this long history of interaction with English. After the French-speaking Normans invaded England in 1066, French enjoyed several hundred years as the primary language of the ruling class in England, and English borrowed many thousands of words from French. As a result, written French looks a bit more like English than other Romance languages do; and written English looks rather more like a Romance language than other Germanic languages do. And ever since the Norman invasion, English and French have been trading words back and forth.

Like genes, words accumulate tiny changes over time. Over long periods of time, words with a shared ancestry can drift apart and become very different in spelling, pronunciation, and/or meaning.

Just like in biological evolution, when populations are separated, they gradually begin to accumulate differences and diverge. Just like these changes can lead to the formation of distinct species, they can lead to the formation of distinct languages.

Over time, these repeated branchings from common ancestors lead to tree-like patterns for both languages and species. Historical linguists were the first to appreciate this, for example in this very early depiction of language evolution, which appeared about 60 years before Darwin published an evolutionary tree as the only figure in his Origin of Species.

Tree of Languages by Félix Gallet, c. 1800
Tree of Languages by Félix Gallet, c. 1800

 

Dawin's Tree
Dawin’s Tree

 

 

 

 

 

 

 

Just like in biological speciation, the process is gradual and boundaries are often fuzzy. American English is a bit different from British English. French people tell me they need subtitles to understand French movies from Quebec.

Many words are spelled pretty much the same in both French and English, especially anything ending in –tion (nation, séduction, production) or –ism(e) (capitalisme, socialisme). These are often words that were recently invented and borrowed.

Older borrowings, which have had more time to evolve, can look quite different. For example, castle and château both come from the Latin common ancestor, “castellum.” The English word is still pretty similar to the Old North French word “castel,” while in French, the hard “c” has turned to a soft “ch” sound and the “s” has disappeared, signaled only by a sort of fossil of an accent mark, the circumflex (ˆ) on the “a,”  which shows there used to be an “s” there.

French has borrowed lots of words from English, which are sometimes obvious (le sandwich, le weekend, le cocktail) but not always: le foot (football), le pull (pullover, sweater).

Many words that English borrowed from French mean quite different things in modern French. Sometimes this is because the English adopted a quite different meaning of the word from how it is used in French. (An entrée is the entry to a meal in French, just a light little starter course, but for some reason an entrée has come to mean the main dish in English.)

But sometimes this is because the French word has continued to evolve in its own course, or been abandoned altogether for another word.

Like dandelion. English borrowed this from the French phrase, dent-de-lion, “lion’s tooth,” a lovely name that must refer to the toothy looking leaves. But apparently, the French don’t call dandelions “dent-de-lions” anymore. Instead, they call them pissenlit – literally, piss-in-bed, because of the plant’s diuretic properties.

Pissenlits in bloom.
Pissenlits in bloom.

Thanks a lot, evolution.

Hunting and Fighting

In chimpanzees, intergroup aggression and hunting look quite similar in several ways. Both hunts and intergroup attacks are mainly the business of males. In both cases, groups of males climb, leap, and run after a victim, which, if they catch, they will bite and pummel until it stops moving. Attacking males bristle their hair like fighting cats, making them look even bigger than they really are. They bare their teeth in fearful grimaces and scream.

Red colobus leaping to escape chimpanzees.

Since the 1970s, researchers have speculated that hunting and fighting in chimpanzees are related, resulting, perhaps, from the same psychological mechanisms. For example, chimpanzees’ close relatives, bonobos, have not been observed to kill other bonobos, and bonobos rarely hunt. Perhaps the two behaviors are linked? For example, my thesis advisor Richard Wrangham has speculated that as bonobos evolved from a chimpanzee-like ancestor, “males lost their demonism, becoming less aggressive to each other. In so doing, perhaps they lost their lust for hunting monkeys, too.” (Wrangham & Peterson 1996: 219)

Ten years ago, when I was a post-doc with Anne Pusey, in the early stages of extracting records on intergroup aggression from the long-term data at Gombe, I looked at seasonal patterns of intergroup encounters, as part of an effort to understand why such encounters occurred. From the limited sample of years for which I’d extracted data, intergroup encounters occurred most often in the late dry season (September and October) with a smaller spike in the middle of the wet season (February). When I compared notes with Anne’s graduate student, Ian Gilby, I was struck that he had found essentially the same pattern with hunts: the number of hunt attempts per follow peaked in the late dry season and mid wet season. Additionally, comparing five years for which we both had data, we found that years with more hunting success also had more patrols. Was this because hunting and intergroup fighting were caused by the same factors?

We agreed we should work on this further, and now that work has born fruit: a forthcoming paper in Animal Behaviour by Gilby, Wilson and Pusey.

Frodo being groomed by Apollo.

A key inspiration for this work was one male chimpanzee, Frodo. Frodo was the best hunter at Gombe when Ian was doing his dissertation research. Frodo was involved in all four intergroup killings that I described in my first Gombe paper (Wilson et al., 2004). I had watched video, frame by frame, of Frodo brutally attacking a young male chimpanzee from the Kalande community. Maybe Frodo was a great hunter because he was a great fighter? Frodo was also exceptionally persistent in pursuit of estrous females, and genetic studies found that Frodo had fathered more babies than any other Gombe male. I began to wonder if in chimpanzees, hunting and fighting were both byproducts of selection for skills needed to achieve mating success.

Male red colobus monkey jumping down to chase Titan, Fundi and Frodo.

Ian kept Frodo very much in mind when he went on to work as a post-doc with Richard Wrangham on data from Kanyawara. Ian proposed that a key part of group hunting in chimpanzees was the presence of particular individuals who really liked to hunt – which Ian termed “impact males.” As a group-level activity, hunting suffers from potential collective action problems. Hunting is risky and dangerous. Red colobus monkeys don’t want themselves or their babies to get eaten, and they fight back fiercely, biting with their sharp teeth. Individuals therefore might be tempted to free-ride – let others do the hunting, and then get meat afterwards, by begging, stealing, or scavenging what’s left when others are done eating. But if everyone free-rides, no one will hunt. So how does hunting get started? Ian proposed that some individuals, the impact males, are strongly motivated to hunt – and once they get started, others are encouraged to join in, because the costs of joining a hunt already in progress are less than the costs of starting the hunt.

Titan, Fundi and Frodo looking at red colobus monkeys, deciding whether to hunt.
Titan, Fundi and Frodo looking at red colobus monkeys, deciding whether to hunt.

The logic of “impact males” made sense to me, not only for hunts, but also for territorial behavior. Patrolling boundaries is energetically expensive and potentially dangerous, as patrols can meet a big group of hostile neighbors. Patrols therefore seem vulnerable to the same collective action problems as hunts. So maybe they are solved the way: some individual males are strongly motivated to go on patrols, reducing the costs for everyone else to join in. After all, if I know at least one of my buddies is going on patrol, I know I won’t be alone at the edge if I go with him. And perhaps – maybe these are all correlated for the same reason? Maybe the same males are impact hunters and impact patrollers? And maybe these same males are the ones who are really good at winning dominance interactions, gaining high rank, and getting access to fertile females and fathering lots of babies? Maybe these are all correlated traits, parts of an overall personality profile or behavioral syndrome of what it takes to be a successful male chimpanzee?

We now had lots more data to work with than we did a decade ago: 32 years of data on both hunting and boundary patrols. And we found that hunting and patrolling boundaries were indeed correlated, not just on a monthly basis, but also on a daily basis. However, it turned out that hunting and patrolling were mainly correlated because of the influence of other variables. Both hunting and patrolling were more common when males were in large parties – which we expected, because parties with more males are more likely to succeed, both in hunts and in intergroup encounters. But the main reason hunting and patrolling were correlated was because both involved long-distance travel. When chimpanzees patrol their borders, they necessarily travel a long ways. And when they travel a long ways, they are more likely to encounter monkeys.

We found that there were indeed impact males for both hunting and patrolling. But only one of the males who was an impact hunter was also an impact patroller. And surprisingly, good old Frodo was neither an impact hunter nor patroller. He had a positive impact on hunting probability, but not enough to merit status as an impact hunter. And the probability of patrolling was the same, with and without Frodo in the party.

So these results suggest that hunting and fighting, despite their many resemblances, may result from different psychological mechanisms. In some ways this is not really surprising, given that in species whose brains have been studied in detail, such as rats and cats, aggression and predation involve quite different regions of the brain. Additionally, Marissa Sobolewski has looked in detail at the hormones of male chimpanzees from the Ngogo community, going on two different kinds of patrols: hunting patrols, in which males are looking for monkeys, and border patrols, in which males are presumably looking for neighbors. Marissa found that testosterone levels were elevated for border patrols, but NOT for hunting patrols. This strongly suggests that hunting and fighting do indeed result from different psychological mechanisms in chimpanzees.

Our findings from the long-term data are thus rather different from what we thought we’d find. This illustrates the importance of looking at data, not just theory, when doing science. It’s easy to fall in love with hypotheses, but they need to stand the test of empirical work. Nonetheless, I still suspect there may be interesting links in the psychology of hunting and fighting. For example, tendencies towards pugnaciousness and risk-seeking seem likely to benefit both hunting and fighting (and acquiring mates). But from the data we’ve examined so far, being a top hunter doesn’t automatically make one an influential boundary patroller.

(For more on Frodo, see Ian’s biography of Frodo, Lisa O’Bryan’s description of Frodo in retirement and this picture of baby Frodo.)

Chimpanzees and humans have similar gut microbes

The human gut hosts numerous species of microbes (the microbiome) — so many that in our bodies, microbe cells outnumber human cells ten to one. Many of these microbes appear to be important for digesting our food and maintaining health, while others have been implicated in disease, such as Crohn’s disease and irritable bowel syndrome. Recent studies have found that human microbiomes can be broadly classified into three enterotypes based on the relative abundance of different microbe species. This finding raised the question: are these enterotypes the product of a long history of co-evolution between microbes and humans, or are they a recent product of changes in diet, such as those resulting from agriculture and processed foods?

Frodo feeding in an oil palm tree.

I played a small role in a recent study led by Howard Ochman that looked at this question. Ochman’s team examined chimpanzee fecal samples collected at Gombe as part of the ongoing study of SIVcpz led by Beatrice Hahn. By comparing the microbiomes of humans and chimpanzees, Ochman’s team found that the microbiomes of wild chimpanzees can be classified into similar enterotypes to those in humans. This suggests that these patterns of microbiome communities are evolutionarily ancient, predating the common ancestor of humans and chimpanzees (some 5 to 7 million years ago).

 

Going Down

23 June 2012

On Saturday, it was time to leave Guassa for the next leg of my journey: Gombe National Park, Tanzania. After breakfast (pancakes with canned peaches and molasses) and packing my bags, I sat with Peter and Tyler in the kitchen tent, asking them about the names of monkeys in my photos, and wondering if the driver would really show up. The project doesn’t have a car in Guassa, so if the car we had hired in Addis failed to turn up, my only option would be to take a walk to the road and take a bus, or try hitching a ride, either of which would mean I would miss my flight to Dar-es-Salaam, and would also miss the two subsequent flights I needed to take to get to Kigoma, before taking the boat to Gombe.

Bus driving through Guassa

Around 10:30 am, the car arrived. The driver had left Addis at 5:00 am to get to Guassa on time.

The drive down was basically terrifying. We rolled into Taitu at 3:18 pm. We left Guassa around 10:45 so that’s 5.5 hours, not bad time. The driver drove typical African style: as fast as possible, on whichever side of the road seemed better paved or reduced curves, honking to alert livestock, cars and pedestrians that he was coming through. The drive was almost entirely downhill, the first few hours especially steep. The road wound in hairpin turns, often with a steep cliff falling away to the side – usually the passenger side. My side.

For most of the way on the gravel road (the first third or so of the drive), there were no barriers at all on the edge of the road to keep a car from driving off into oblivion. On the paved road, several different kinds of barriers existed: stone and concrete rectangles built like castle fortifications, thick concrete posts, metal stakes, and the sort of metal ribbon we are used to in America. And almost every single one of these barriers showed signs of having been run into at high speed. We passed one truck with a double trailer dangling off a bridge, and several other trucks in various states of damage along the side of the road, rocks under the tires to keep them from rolling further, and more rocks and tree branches placed around the disabled truck as a helpful barrier and warning sign to oncoming traffic.

Eucalyptus plantation

We passed through Eucalyptus plantations growing on the steep hills. These exotic trees are planted widely in Africa, and valued because they grow quickly, and also sprout new shoots from the stump when you cut the tree down. The many small trunks growing from older stumps seem to be the main source of the scaffolding used in the many new buildings going up in Addis: spindly trunks of

Scaffolding on new construction in Addis Ababa

young trees roughly lashed together to provide a rickety framework for new multi-story concrete office and apartment buildings. We passed trucks belching black exhaust and diesel fumes with bundles of Eucalyptus poles tied to the truck bed, the leafy treetops extending far over the cab of the truck.  Donkeys carried loads of smaller Eucalyptus branches, maybe for use in building the framework for wattle and daub houses.

In Addis, I took a long hot shower, my first since leaving the city on Monday. It was just too cold to bathe in Guassa. Then I had dinner. I ordered Special Tibs again. On previous nights, the mound of spicy meat and sauce and two rolls of injera seemed like more food than I could possibly manage, and I ended dinner stuffed and defeated before finishing it all. But now with a Guassa stomach, the meal looked disappointingly small. But with the addition of some extra njera the tibs proved highly satisfying.

Wolves

22 June 2012

After a long and rewarding day with the monkeys, the sun began to dip towards the horizon. Tyler suggested we leave the monkeys early to go looking for wolves. Ethiopian wolves are one of the highlights of Guassa, and Tyler didn’t want me to leave without seeing one.

Ethiopian wolves, like gelada monkeys, are endemic to the Ethiopian highlands: they don’t occur anywhere else. The highlands are so different and isolated from the surrounding lands that all sorts of unusual things have evolved here.

They are small for a wolf. They don’t get much bigger than 40 pounds. They eat mainly rodents, which are abundant at Guassa. The wolves don’t seem to pose any sort of threat to gelada monkeys, despite being depicted as hunting geladas in at least one nature documentary.  They look more like a large fox or a coyote than a wolf, with a reddish coat. And indeed, when speaking English, Ethiopians seem to mainly call them “red foxes.”

But genetically, they are closely related to grey wolves, having diverged from them some 3-4 million years ago. And they are extremely rare. Only about 550 of them survive in the wild, of which something like 30 live at Guassa.

Before we left the monkeys, Tyler talked to Tayler, who has been searching for wolves on his days off. Taylor recommended several spots, including the big valley close to camp. So we left the monkeys and walked back towards camp, stopping now and then to look for wolves. As we approached the valley, we left the road and climbed a hill that gave a broad view across the valley. Tyler scanned the valley with binoculars, and before too long, found a pair of wolves on a distant ridge. With some help, I eventually found them too.

We sat on the hillside and watched the wolves, which were far beyond camera range. After a few minutes, the wolves trotted up the hill and out of view. Tyler said the wolves were shy, and I wasn’t expecting get close enough to take pictures; I was excited just to have caught a glimpse of these rare creatures.

We sat and scanned the valley some more, and eventually Tyler spotted two more wolves, some six or seven hundred meters away, on the other side of the valley, close to the road. People herding cattle or driving down the road didn’t seem to notice the wolves at all. I wondered how many times we had walked past wolves without seeing them. Despite their reddish-orange and white coats, they blended easily into the green-grey heathland.  When I put the binoculars down to rest my eyes a bit, I couldn’t see the wolves at all with my naked eyes, and had trouble finding them again with the binoculars.

Peter commented that these four wolves represented nearly 1% of the entire population of the species. They are reasonably well protected on Guassa, but still face threats, such as rabies, which has killed hundreds of wolves, and cars, which occasionally kill wolves crossing the road.

Tyler speculated that these two wolves we were looking at now might be the grown offspring of the pair we had seen earlier. After watching the wolves through binoculars for a good long time, Tyler suggested we try moving closer to them. We walked slowly down the hill. Tyler suggested we walk towards a ridge that ran between us and the wolves, so we could get closer to them without them seeing us. The plan worked a little too well.  By the time we climbed the top of that ridge, we found that one of the wolves walking right past us, and it startled, running another hundred meters or so away from us before turning back to look at us. We watched it slowly walk away, then began making our way to camp.

I lagged behind to put my camera away and take a GPS reading. Tyler and Peter walked ahead to the road. Suddenly I heard them calling “Mike! Mike!” I wondered if they worried I was lost. I called out, “I’m here!” then saw why they were yelling: a wolf was running right toward me! I hurried to get my camera out. Putting the camera away seemed to be a sure way to attract wolves.

Peter and Tyler had caught this wolf by surprise, and it quickly ran away, off towards the same direction where the other wolf had gone. Now it got another surprise: me. But though it seemed startled to see me, it didn’t seem especially concerned. It trotted past me, then turned to look at me, letting me take some pictures.

 

Ethiopian wolf sitting

It even sat down and scratched itself a bit.

 

 

 

 

 

 

 

 

Hunting for rats

Then it hunted in the heather for rats: peering into the heather and then making funny bouncing hops towards its prey. It failed to catch anything, then trotted away at a leisurely pace.

 

 

 

Who’s Your Daddy?

22 June 2012

I slept in the same clothes I’d been wearing for days: t-shirt, long-sleeved flannel shirt, long-sleeved field jacket, field pants and thick socks, huddled in a sleeping bag with a thick wool blanket on top. No mosquitos, no malaria, no snakes, no warmth – is this really Africa? Hardly feels like it.

Researchers arriving at Darjeeling as the morning fog starts to clear

Soon after breakfast, a thick fog rolled in. We started the hike down to Darjeeling Cliff where the geladas had spent the night. I wore the waterproof rainboots I had worn the previous two days, but found were killing my feet. It didn’t look like rain, so I returned to camp and put on the Kiboko soccer cleats that I had brought for Gombe. Much more comfortable.

We hiked several kilometers down to the cliffs, and found some of the geladas already up at the top, basking in the sun, grooming, and starting to feed. We followed them as they traveled in a long circuit through the open hills. This southern area looked strangely like the Great Basin in the American West: grassy hills and open plains studded with stark masses of rock, the bushy grey-leaved Helichrysum filling in for sagebrush.

Gelada female picking grass

The geladas ate and ate, sitting on their bottoms, plucking grass and herbs with their nimble hands and stuffing their mouths. So many monkeys plucking grass at once made a surprisingly loud munching sound, rather like a horde of locusts.

Geladas have such an interesting social system – one with some interesting parallels with human society. Like humans, geladas live in a multi-level society with strong bonds between males and females. They travel in herds made up of one-male units (OMU’s). Each OMU has a leader male, a ‘harem’ of females, their offspring, and sometimes one or more follower males. Each leader male tries to keep all the females in his harem to himself. But because the OMUs travel together in herds that may have hundreds of monkeys, there are always other males around, particularly the bachelor males, who hang around the periphery in menacing groups of unattached males.

In my own research, I focus on chimpanzees, which are much more closely related to humans than are gelada monkeys. The last common ancestor of chimpanzees and humans lived something like five to six million years ago, whereas the last common ancestor of humans and Old World Monkeys such as geladas lived perhaps 30 million years ago. But social structure can evolve quickly in response to ecological conditions and other factors. And in some ways, geladas, living in open country, may face ecological circumstances that are rather similar to those faced by our hominin ancestors, who also lived in the more open habitats of East Africa, compared to chimpanzees, which live in forests and woodlands.

In chimpanzees, males and females don’t have strong social bonds or anything like marriage. Instead, females attempt to mate with many different males. Males may try to keep other males from mating with a particular fertile female, but unless the male is especially intimidating, or manages to sneak off on consort with a female, the female usually mates with multiple males. The result is that chimpanzee males don’t know for sure who their children are, and no chimpanzee knows for sure who his or her father is. Even the researchers studying chimpanzees, keeping close tabs on every mating, couldn’t be sure who the fathers were before the advent of genetic paternity tests.

In contrast, in gelada monkeys, males and females do have strong social bonds. Each leader male grooms and herds and mates with and jealously guards the females in his harem. As a result, gelada monkeys likely do know who their daddies are.

There are other primates, like gibbons and titi monkeys, in which males and females live in monogamous pairs, with strong male-female social bonds. And there are other species, like gorillas and blue monkeys, where groups usually have a single male and harem of females. What is unusual about geladas is that they, like humans and a few other species, live in societies with strong bonds between males and females, not as isolated family units, but as members of complex multi-level societies.

Danzig in the heather showing off his fangs

Because competition for mates is intense, males are big and showy, nearly twice the size of females, with massive canines and flowing manes of hair. With their big hair and strutting posture, they look like heavy metal rockers, and they have been giving fitting names: Lars, Danzig, Ulver, Mustaine.

In the mid-afternoon, the geladas plucked short grasses from a meadow strewn with yellow flowers. Around 120 monkeys foraged together. We were closest to a one male unit led by Ptolomy. Though he was clearly the leader male, he still had to contend with two follower males: Cthulu, who had briefly reigned before Ptolomy deposed him, and Tony, who had enjoyed a long reign before being overthrown by Cthulu.

A female with a full red chest, Tatanga, presented to Ptolomy. He started to mate with her, but then he looked over and saw Tony, some thirty yards away, flashing his eyelids at him. How dare he! Though Ptolomy had just begun mating, he dismounted Tatanga and strode threateningly to Tony, who flipped his upper lip over his teeth, staring back at Ptolomy. Cthulu stood behind Tony, lending his support. Tony carried a baby on his back – probably one of his own babies, since he had enjoyed a long tenure as leader male. Males often use infants in fights with other males, though nobody really knows why they do this.

Tony flipping his lip at Ptolomy, with Cthulu behind and a baby on his back.

Ptolomy walked right up to Tony and stared into his face. Tony kept his lip flipped up and opened his jaws, showing off his huge canines. Cthulu flipped his lip and showed off his own fangs. This was the last straw for Ptolomy, who lunged right at both of them – and soon ran off into the hills, with the other two males chasing right behind him. To me, it looked like Ptolomy had been chased off by the other, lower ranking males, which surprised me. Peter explained, though, that such interactions often ended up that way. The leader males often ran ahead, letting the lower ranking male chase them. Maybe the leader males do this to show off their stamina.

Ptolomy (left) facing off with Tony and Cthulu

So Tony, despite being an old deposed former leader male, could still get away with interrupting the new leader male’s mating efforts. And Tony seemed always to be surrounded with little kids, who were almost certainly his.

 

Ptolomy and Tony lunging at each other

 

 

 

 

 

Ptolomy showing Tony and Cthulu who's boss by running away from them.

Vertigo

20 June 2012

I woke up several times in the night, but I finally woke up to see dawn light filtering into the tent, instead of the pitch black of night. Used to studying chimpanzees, who often leave their night nests before dawn, I felt I had overslept.  I unzipped the tent and went into the kitchen tent. Tyler was there heating water for tea and oatmeal. I thought everyone else must have already left for the monkeys. But no, as it turns out, geladas are lazy monkeys. As Taylor says, “they are solar powered.” They sleep on cliffs, and bask in the morning sun before climbing up to the grasslands above. Even then they may sit around socialize a while before starting the day’s main business: feeding.

The others came in one by one and fixed their breakfast and lunch. Unlike dinner, each person fixed their own breakfast and packed their own lunch, some more elaborate than others. Taylor eagerly prepared a sardine and salad sandwich from one of the five cans of sardines Tyler had bought for him in Addis. For our first day at Guassa, Tyler and I wouldn’t be going out all day, so we would come back for lunch.

It takes time for a body to adjust to 11,000 feet. There’s a lot less oxygen in the air. “I’m sucking wind just walking up the hill a bit,” Tyler commented ruefully.

The geladas had been spending a lot of time in the south of their range, but Tyler wanted me to see the north, with its spectacular views. So for our first day out, we went on a gentle hike, together with Peter.  But even this left me winded. I stopped frequently to look at plants, take pictures and catch my breath.

Helichrysum flowers

Up close, Guassa looks like a giant herb garden. Thyme covers much of the ground, along with Helichrysum, bushy little plants with silvery gray leaves and bright yellow flowers, and other low-growing plants: clover, daisies, dandelions, two kinds of carrots, an onion, and many others I didn’t recognize.

Tyler and Peter watching geladas, with giant lobelias.

Occasional stands of giant lobelias made clear that we were in the African mountains. These odd herbs look a bit like Joshua trees. Peter says that the ones at Guassa grow until they flower and then die, to be replaced by clones of the original plants. I knew these plants from the books and magazine articles on mountain gorillas by George Schaller and Dian Fossey that first made me want to become a primatologist.

We walked along a path through flowers and herbs, through stands of giant lobelias and giant celery. I asked Peter what the strange bushy plant with scaly leaves, and he said it was heather – which just confirmed my impression that we had somehow ended up in Scotland by mistake.

Tyler on ridge looking at cliffs and valley.

I had imagined that above the cliffs where the geladas slept, the grassland would be a gently rolling plateau. There were some places like that, but for the most part, here the cliffs were topped with steep hills, including the one that we were walking along. It was a long way down. Peter and Tyler said it was too bad about all the haze; you could normally see much further. But it looked like we could see plenty far down as it was.

View of the farms far below us.

At one point where we stopped, Peter said it was about a full kilometer down to the valley bottom. I’ve been up to the observation decks of a few skyscrapers, but the tallest of these, the Sears Tower in Chicago, is just over 440 meters, less than half the height that we now stood above the valley. We looked down to fields and round farmhouses topped with conical thatched roofs, spread out like a map below us.

Tyler spotted gelada monkeys on the steep slope of a hill above the cliff across from us. It seemed impossible to get from here to there without falling off the hill into the abyss. But still we went – and for the most part, found that even though the hills looked impossibly steep, if you stepped the right way, you could get around.

We met the geladas at closer range as they came up the hill. They let us come close, so they were used to seeing people, but they weren’t named individuals from study groups.

Gelada male showing off his bare chest and orange eyeshadow.

Geladas are strange monkeys. The females look rather like small olive baboons, but with thick, fluffy hair, and strange bare patches of red skin on their chest. The males look like little lions. They have long manes and tufted lion tails. Like females, they have bare red patches on their chests. They also have orange shadow all around their eyes, and when making threats, they raise their eyebrows to show off the orange.

Female geladas and a baby

Baboons display lots of information about their reproductive status on their bottoms. Females have bright red swellings that indicate when they are ovulating, and a pregnancy sign that turns red when they have a baby on board. Geladas, though, spend much of the day scooting around on their bottoms, eating grass. A big swelling would get in their way while scooting, and you couldn’t see it anyway. So they display their reproductive condition on their chests instead. (They do get little swellings on their bottoms, just nothing as dramatic as baboons.)

In The Naked Ape, Desmond Morris argued that over the course of human evolution, a similar relocation of reproductive signals occurred. Just as in baboons, in our closer cousins, chimpanzees and bonobos, females signal ovulation with big swellings on their bottoms, suggesting that our common ancestor also may have had sexual swellings on their bottoms. Chimp swellings don’t look terribly comfortable or convenient, but as they mainly get around by walking on all fours, using their feet and knuckles, the swelling doesn’t get in the way much. With the evolution of a bipedal gait, however, the area that swells in chimps ended up between the legs, where a big swelling would make it hard to walk – and a small swelling would be hard to see. So, Morris argued, the main female visual signals, and corresponding male interest, shifted up from the bottom to the chest.

If Playboy published editions for chimps and baboons, they would feature lots of rear views. Playboy Gelada, however, would be all about the frontal shots.

Later, back at camp, I met a group of four bachelor males who were foraging in the grass just beyond the kitchen tent. If these were Gombe baboons, they would be racing into the kitchen tent to steal all our food. But gelada monkeys don’t seem to care about our food. They were content to skirt the camp, just looking for grass and herbs to eat.

At one point, I heard strange high-pitched calls coming from up the hill. The gelada bachelors noticed too – they looked up and stared towards the calls. Walking into camp, I found others looking up the hill. “Did you hear the wolves calling?” they asked.

So, just like when camping up in northern Minnesota, there’s a chance of hearing wolves here. But Ethiopian wolves are much smaller, and have a high-pitched whistling call, much different from the haunting howl of the gray wolf. Still, it was tremendously exciting to hear the call of these rare creatures, which only live in the Ethiopian highlands.

 

thoughts on primates, people, and evolution