Posts Tagged ‘Neanderthals’
back to bonobos – and sex
Canto: We’re reading Rebecca Wragg Sykes’ brilliant book, Kindred, an almost up-to-date account (published in 2020) of all the new discoveries about our close relatives the Neanderthals, and the speculations resulting from them. And of course we’re always alert to the slightest mention of bonobos in any works of anthropology…
Jacinta: Yes, we’ve been a bit timid about talking too much about bonobos and sex, but a few mentions in Kindred have emboldened us.
Canto: W’ve seen the odd photo or video of chimps or bonobos with erect penises, and it was a scary but also puzzling sight, but we’ve not really explored the difference between theirs and ours, so now is the time to do so. So here’s some interesting comments linking humans, Neanderthals and our chimp/bonobo rellies:
Anatomically, pelvic dimensions point to vaginas very similar to ours, and as penises are tailored to fit, those too were probably more like living men’s equipment than that of chimpanzees.
Luckily for all concerned, unlike chimps Neanderthal males lacked the genes for ‘penis spines’. While in apes they’re more like tiny hardened pebbles than spikes, their presence does affect copulation: marmosets have sex and orgasms that last twice as long when the spines are removed.
We should probably therefore picture Neanderthal sex as more leisurely and satisfying than chimp-style rapid thrusting bouts. Not forgetting clitorises – organs solely existing for pleasure – unluckily for Neanderthals, like us they probably lacked bonobo-like versions that make face-to-face orgasms easier. But masturbation in some form is pretty much guaranteed, whether during sexual encounters as is found among humans, or more generally for social bonding and diffusing tensions, as in bonobos where it takes place between pretty much anyone.
Kindred, Rebecca Wragg Sykes, p 271
Jacinta: So this makes me want to know more about the bonobo penis, and ‘penis spines’. It sounds like it isn’t ‘made for pleasure’, which helps to explain why female-female sex is the most practised type among bonobos.
Canto: Then again chimps have the same penises as bonobos but they’ve evolved differently. So here we go with ‘penile spines’. First, Wikipedia:
Many mammalian species have developed keratinized penile spines along the glans and/or shaft, which may be involved in sexual selection. These spines have been described as being simple, single-pointed structures (macaques) or complex with two or three points per spine (strepsirrhines). Penile spine morphology may be related to mating system.
This is news to me, but fascinating.
Jacinta: Just up our alley, so to speak. So to elaborate on this last quote, again using Wikipedia (largely), strepsirrhines are a suborder of primates including lemurs, galagos or bushbabies, pottos and lorises. Sexual selection is, I presume, a form of mating system, which Darwin reflected upon in The Descent of Man, inter alia. Macaques are a type of Old World monkey, with 23 known species. Interestingly, they’re matriarchal and frugivorous, like bonobos.
Canto: Apparently they’re a feature of felines – penile spines, that is. In cats, it’s speculated that they may contribute to pregnancy, as they ‘rake the walls of the female’s vagina [during withdrawal], which may serve as a trigger for ovulation’. I’m wondering, though, how that might relate to sexual selection. ‘A spiny dick, nothing turns me on more.’
Jacinta:
It all works below the conscious level, mate. I mean, female bowerbirds hang out with the males with the best display, but I don’t think they’re thinking about sex, especially considering how much of a nothing bird sex generally is. But getting back to bonobos, Wragg refers in the above quote to ‘bonobo-like’ clitorises that make face-to-face orgasms easier than it was for Neanderthals and, more to the point, we H sapiens. How could we have missed this in all our explorations of the bonobo world?
Canto: Hmmm. I blame the prudery of researchers. Including ourselves. Anyway, it probably all gets back to genes and their expression. So we need to explore – but should we look at penises first or clitorises – is that the plural?
Jacinta: Not sure, I can only cope with one at a time. So here’s something we should never have missed:
Bonobo clitorises are larger and more externalized than in most mammals; while the weight of a young adolescent female bonobo “is maybe half” that of a human teenager, she has a clitoris that is “three times bigger than the human equivalent, and visible enough to waggle unmistakably as she walks”. In scientific literature, the female–female behavior of bonobos pressing genitals together is often referred to as genito-genital (GG) rubbing. This sexual activity happens within the immediate female bonobo community and sometimes outside of it. Ethologist Jonathan Balcombe stated that female bonobos rub their clitorises together rapidly for ten to twenty seconds, and this behavior, “which may be repeated in rapid succession, is usually accompanied by grinding, shrieking, and clitoral engorgement”; he added that it is estimated that they engage in this practice “about once every two hours” on average. As bonobos occasionally copulate face-to-face, evolutionary biologist Marlene Zuk has suggested that the position of the clitoris in bonobos and some other primates has evolved to maximize stimulation during sexual intercourse. The position of the clitoris may alternatively permit GG-rubbings, which has been hypothesized to function as a means for female bonobos to evaluate their intrasocial relationships.
Canto: What can I say?
Jacinta: So this quote, from Wikipedia, compares the bonobo clit to the human one, but says nothing about chimps. I mean, it occurs to me that this enlarged clit, and the pleasure derived from it, would help to explain female-female sexual bonding, leading to social bonding, leading perhaps to matriarchy, if we can call it that. But if chimps have the same-size female pleasure-place, that thesis collapses.
Canto: Good point. So, googling ‘chimp clitoris’ takes me first to an essay from nearly 40 years ago on ‘The external genitalia of female pygmy chimpanzees’, an early term for bonobos. The abstract actually compares Pan paniscus (bonobos) and Pan troglodytes (chimps) as if just to resolve your dilemma:
The external genitalia of four adult female pygmy chimpanzees (Pan paniscus) were examined during a 2-year period. It was found that the labia majora are retained in adults of this species and that, when tumescent, the labia minora effectively relocate the frenulum and clitoris so that they point anteriorly between the thighs. When detumescent, the configuration of the labia minora and clitoris resembles that of immature common chimpanzees (P. troglodytes). It is suggested that the simple, structural relocation of the clitoris from the normal [sic] condition noted in adult P. troglodytes makes possible the homosexual, intergenital rubbing observed in P. paniscus, when ventroventral juxtaposition of the individuals permits eye-to-eye contact. In addition, this change probably increases sexual stimulation of the female during heterosexual, ventroventral copulations.
Jacinta: Wow. So bonobos separated from chimps between 1 and 2 million years ago. And in that time a kind of structural change took place in the positioning of the clitoris. Is that plausible? And what about the swelling?
Canto: Hard to get clear info, but the general genital swellings of chimps versus bonobos differ in one respect – in chimps, they’re indicative of fertility, or ovulation, but bonobos, like humans have ‘concealed’ ovulation. A wonder that this can occur in the relatively short time since the split. Or maybe not, I’m no primatologist.
Jacinta: Apparently bonobos and humans aren’t the only primates with concealed ovulation – it also occurs in Vervet monkeys, but the very concept of ‘concealed ovulation’ is a bit controversial – as if it’s being done deliberately, which would surely be absurd. But it certainly does mean that, in those primates that don’t exhibit clear signs of ovulation, copulation occurs through all stages of the menstrual cycle. It could be a way of preventing males from being aware of their own offspring, thus reducing the infanticidal tendencies found in male, and sometimes female, chimps. As for the position of the clitoris, its shift to a more ‘accessible’ spot for genito-genital rubbing in bonobos is often mentioned as a great development for female bonding, but I can find nothing much on how this anatomical change could’ve happened.
Canto: Well, think of Darwin’s finches in the Galapagos. Certain beak shapes were more adaptive to the particular vegetation on particular islands, and birds with those beak shapes outbred other birds and became dominant, and ultimately the outright winners. With bonobos, okay this different clitoral positioning might not have led directly to those females outbreeding other females, since it might not have made it easier for males to have sex with females (though where there’s a willie there’s a way), but it might have led indirectly to females becoming dominant through sexually stimulated female bonding, allowing the females with the most changed and, to females, most alluring clitorises to choose the most male partners and so produce the most offspring.
Jacinta: Female rather than male choice. Or even females ‘sexually assaulting’ males? Definitely sounds interesting. But as always, more research is required…
References
Rebecca Wragg Sykes, Kindred: Neanderthal life, love, death and art. 2020
https://pubmed.ncbi.nlm.nih.gov/3985376/
https://en.wikipedia.org/wiki/Strepsirrhini
https://en.wikipedia.org/wiki/Macaque
https://en.wikipedia.org/wiki/Bonobo
https://www.scientificamerican.com/article/bonobo-sex-and-society-2006-06/
language origins: some reflections
smartmouth
Jacinta: So a number of readings and listenings lately have caused us to think about how the advent of language would have brought about something of a revolution in human society – or any other society, here or on any other planet out there.
Canto: Yes, we heard about orangutan kiss-squeaks on a New Scientist podcast the other day, and we’re currently reading Rebecca Wragg Sykes’ extraordinary book Kindred, a thoroughly comprehensive account of Neanderthal culture, which we’ve clearly learned so much more about in recent decades. She hasn’t really mentioned language as yet (we’re a little over halfway through), but the complexity and sophistication she describes really brings the subject to mind. And of course there are cetacean and bird communications, inter alia.
Jacinta: So how do we define a language?
Canto: Yeah, we need to define it in such a way that other creatures can’t have it, haha.
Jacinta: Obviously it evolved in a piece-meal way, hence the term proto-language. And since you mentioned orangutans, here’s a quote from a 2021 research paper on the subject:
Critically, bar humans, orangutans are the only known great ape to produce consonant-like and vowel-like calls combined into syllable-like combinations, therefore, presenting a privileged hominid model for this study.
And what was the study, you ask? Well, quoting from the abstract:
… we assessed information loss in proto-consonants and proto-vowels in human pre-linguistic ancestors as proxied by orangutan consonant-like and vowel-like calls that compose syllable-like combinations. We played back and re-recorded calls at increasing distances across a structurally complex habitat (i.e. adverse to sound transmission). Consonant-like and vowel-like calls degraded acoustically over distance, but no information loss was detected regarding three distinct classes of information (viz. individual ID, context and population ID). Our results refute prevailing mathematical predictions and herald a turning point in language evolution theory and heuristics.
Canto: So, big claim. So these were orangutan calls. I thought they were solitary creatures?
Jacinta: Well they can’t be too solitary, for ‘the world must be orangutan’d’, to paraphrase Shakespeare. And interestingly, orangutans are the most tree-dwelling of all the great apes (including us of course). And that means a ‘structurally complex habitat’, methinks.
Canto: So here’s an even more recent piece (December 2022) from ScienceDaily:
Orangutans’ tree-dwelling nature means they use their mouth, lips and jaw as a ‘fifth hand’, unlike ground-dwelling African apes. Their sophisticated use of their mouths, mean orangutans communicate using a rich variety of consonant sounds.
Which is interesting in that they’re less close to us genetically than the African apes. So this research, from the University of Warwick, focused a lot on consonants, which until recently seemed quintessentially human productions. Researchers often wondered where these consonants came from, since African apes didn’t produce them. Their ‘discovery’ in orangutans has led, among other things, to a rethinking re our arboreal past.
Jacinta: Yes, there’s been a lot of focus recently on vowel and consonant formation, and the physicality of those formations, the muscles and structures involved.
Canto: Well in this article, Dr Adriano Lameira, a professor of psychology who has long been interested in language production, and has been studying orangutans in their natural habitat for 18 years, notes that their arboreal lifestyle and feeding habits have enabled, or in a sense forced, them to use their mouths as an extra appendage or tool. Here’s how Lameira puts it:
It is because of this limitation, that orangutans have developed greater control over their lips, tongue and jaw and can use their mouths as a fifth hand to hold food and manoeuvre tools. Orangutans are known for peeling an orange with just their lips so their fine oral neuro-motoric control is far superior to that of African apes, and it has evolved to be an integral part of their biology.
Jacinta: So they might be able to make more consonantal sounds, which adds to their repertoire perhaps, but that’s a long way from what humans do, putting strings of sounds together to make meaningful ‘statements’. You know, grammar and syntax.
Canto: Yes, well, that’s definitely going to the next level. But getting back to those kiss-squeaks I mentioned at the top, before we get onto grammar, we need to understand how we can make all the sounds, consonantal and vowel, fricative, plosive and all the rest. I’ve found the research mentioned in the New Scientist podcast just the other day, which compares orangutan sounds to human beatboxing (which up till now I’ve known nothing about, but I’m learning). Dr Lameira was also involved in this research, So I’ll quote him:
“It could be possible that early human language resembled something that sounded more like beatboxing, before evolution organised language into the consonant — vowel structure that we know today.”
Jacinta: Well that’s not uninteresting, and no doubt might fit somewhere in the origins of human speech, the details of which still remain very much a mystery. Presumably it will involve the development of distinctive sounds and the instruments and the musculature required to make them, as well as genes and neural networks – though that might be a technical term. Neural developments, anyway. Apparently there are ‘continuity theories’, favouring gradual development, probably over millennia, and ‘discontinuity theories’, arguing for a sudden breakthrough – but I would certainly favour the former, though it might have been primarily gestural, or a complex mixture of gestural and oral.
Canto: You’d think that gestural, or sign language – which we know can be extremely complex – would develop after bipedalism, or with it, and both would’ve evolved gradually. And, as we’re learning with Neanderthals, the development of a more intensive sociality could’ve really jump-started language processes.
Jacinta: Or maybe H sapiens had something going in the brain, or the genes, language-wise or proto-language-wise, that gave them the competitive advantage over Neanderthals? And yet, reading Kindred, I find it hard to believe that Neanderthals didn’t have any language. Anyway, let’s reflect on JuLingo’s video on language origins, in which she argues that language was never a goal in itself (how could it be), but a product of the complexity that went along with bipedalism, hunting, tool-making and greater hominin sociality. That’s to say, social evolution, reflected in neural and genetic changes, as well as subtle anatomical changes for the wider production and reception of sounds, perhaps starting with H ergaster around 1.5 million years ago. H heidelbergensis, with a larger brain size and wider spinal canal, may have taken language or proto-language to another level, and may have been ancestral to H sapiens. It’s all very speculative.
Canto: Yes, I don’t think I’m much qualified to add anything more – and I’m not sure if anyone is, but of course there’s no harm in speculating. Sykes speculates thusly about Neanderthals in Kindred:
Complementary evidence for language comes from the fact Neanderthals seem to have had similar rates of handedness. Tooth micro-scratches and patterns of knapping on cores [for stone tool-making] confirm they were dominated by right-handers, and this is also reflected in asymmetry in one side of their brains. But when we zoom in further to genetics, things get increasingly thorny. The FOXP2 gene is a case in point: humans have a mutation that changed just two amino acids from those in other animals, whether chimps or platypi. FOXP2 is definitely involved with cognitive and physical language capacity in living people, but it isn’t ‘the’ language gene; no such thing exists. Rather it affects multiple aspects of brain and central nervous system development. When it was confirmed that Neanderthals had the same FOXP2 gene as us, it was taken as strong evidence that they could ‘talk’. But another, subtler alteration has been found that happened after we’d split from them. It’s tiny – a single protein – and though the precise anatomical effect isn’t yet known, experiments show it does change how FOXP2 itself works. Small changes like this are fascinating, but we’re far from mapping out any kind of genetic recipe where adding this, or taking away that, would make Neanderthals loquacious or laconic.
Rebecca Wragg Sykes, Kindred: Neanderthal life, love, death and art, pp 248-9
Jacinta: Yes, these are good points, and could equally apply to early H sapiens, as well as H ergaster and H heidelbergensis. Again we tend to think of language as the full-blown form we learn about in ‘grammar schools’, but most languages today have no written form, and so no fixed grammar – am I right?
Canto: Not sure, but I understand what you’re getting at. The first English grammar book, more like a pamphlet, was published in 1586, when Shakespeare was just starting out as a playwright, and, as with ‘correct’ spelling and pronunciation, would’ve been politically motivated – the King’s English and all.
Jacinta: Queen at that time. Onya Elizabeth. But the grammar, and the rest, would’ve been fixed enough for high and low to enjoy Shakespeare’s plays. And to make conversation pretty fluid.
Canto: Yes, and was handed down pretty naturally, I mean without formal schooling. It’s kids who create new languages – pidgins that become creoles – when necessity necessitates. I read that in a Scientific American magazine back in the early eighties.
Jacinta: Yes, so they had the genes and the neural equipment to form new hybrid languages, more or less unconsciously. So much still to learn about all this…
Canto: And so little time….
References
Kindred: Neanderthal life, love, death and art, by Rebecca Wragg Sykes, 2021
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8478518/
https://www.sciencedaily.com/releases/2022/12/221220112426.htm
https://www.sciencedaily.com/releases/2023/06/230627123117.htm
https://en.wikipedia.org/wiki/Origin_of_language
https://humanorigins.si.edu/evidence/human-fossils/species/homo-heidelbergensis
humans and neanderthals and chimps and bonobos
We now know for sure that humans and neanderthals interbred. How much, we don’t know, nor do we know the nature of the interbreeding. The spectrum presumably goes from love and flowers to warfare slaughter and rape, and I recently heard one pundit arguing for the latter option, and I tend to agree, especially given what information ancient DNA is providing about human populations over the last 50,000 years or so – that’s to say, it appears that it was much less a case of cultures and practises spreading from one place to another than populations replacing earlier populations. And it may well be that we’ll get a more gory-detail picture of human-neanderthal intimacies in the foreseeable.
We’ve also learned that chimps and bonobos bonked after their separation due to the creation of the Congo River between one and two million years ago. I wish I’d been there to see it. My guess is that would’ve been far less traumatic, though perhaps not too lovey-dovey either.
So if we accept that violence was involved – who were the perps and who the victims? My feeling is that humans were the rapists, for the simple reason that we’re still here. Neanderthals disappeared some 40,000 years ago, though a remnant population appears to have survived in the Iberian Peninsula for another few thousand years. With chimps and bonobos it was probably more fifty-fifty, though I’m prepared to accept that nothing is ever that simple.
The fact that many of us – I don’t know about me – have some neanderthal DNA is probably a mixed blessing (some genes for absorbing sunlight may have predisposed us to skin cancer, others may have affected our ability to process carbs), but it hasn’t prevented us from quadrupling our population in the last century. And since we’ve produced the first whole-genome sequence of the neanderthal genome, they’ll soon be back with us, so no worries. Unfortunately, their memories of what we did to them will have been wiped, but we’re working on it.
Seriously, humans most likely were one of many contributors to neanderthal extinction. The two species shared similar European territories for the last few millennia before their disappearance, with human numbers apparently growing as neanderthals dwindled. Maybe they were out-competed in hunting big game, and small, as their diets would’ve been more or less identical to ours. Studies of neanderthal teeth from different environments (north-west and south-west Europe) indicate that they were opportunistic dieters, eating more meat in some regions, less in others, not all-out carnivores as previously thought, so this brings them even closer in line with humans, and in competition with them when habitats overlapped. And if anything, ancient DNA is telling us that our human ancestry was even more violent than previously thought – and we’ve long known how bad it was.
We don’t have any direct evidence that modern humans killed neanderthals, and we may never have such evidence. Professor Chris Stringer of London’s Natural History Museum argues that, as we now know that both species inhabited Western Europe for about 10,000 years before neanderthals died out, there was more likely a kind of awkward balance between the two species for much of that time. So, maybe killing but not outright extermination. Of course the same can be said for the large mammals that humans hunted. There was never any intention to exterminate them, but the pressure they were put under did for them in the end.
With chimps and bonobos, that seems to me even more of a mystery. What does a chimp look like to a bonobo, and vice versa? Most of us wouldn’t be able to tell one from the other, but that’s because we’re humans. In the past, Europeans used to say that all Chinese looked the same. Back in Darwin’s day and before, the people of Africa, Australia and Indonesia were collectively termed ‘savages’ by ‘white’ people. It’s taken a while for us dumb humans to become more discriminating. So it’s hardly surprising that bonobos weren’t recognised as a separate species from chimps until well into the twentieth century. Speciation itself is a rather more complicated and questionable affair than it was thought to be in the time of Linnaeus – and it wasn’t particularly simple then. Here’s an interesting quote from a Science article on chimp-bonobo interbreeding:
These findings come on the heels of other genome analyses—such as between coyotes, dogs, and wolves—showing such gene flow between species. “The more we look at genomes, the more it seems to be found,” [Professor Jim Mallet] says. “It’s going to be pretty common,” he predicts.
An article in earth.com, a popular science site, linked below, provides a summary of the physical and social differences between bonobos and chimps, though I can’t vouch for its accuracy – for example it claims that bonobo males and females are ‘much closer in size’ than chimp males and females. I’d always thought that the sexual dimorphism difference was slight, now I’m not so sure. Another interesting difference, that I’d not noticed before in my reading, is that bonobos have dark faces from birth, whereas chimps’ faces are lighter, and darken with age. I can well believe though that there are individual differences, in this as in robustness and gracility, bonobos being in general more gracile. Of course, chimp males are more dominant, so I can well imagine chimp-bonobo interbreeding to be a violent affair. And with bonobo females tending to stick together it would’ve been difficult to pick off an isolated female. Perhaps we should build a few Pan-friendly bridges across the Congo River and see what happens….
References
https://www.americanscientist.org/blog/science-culture/neanderthals-in-prime-time
https://www.science.org/content/article/chimps-and-bonobos-had-flings-and-swapped-genes-past
https://www.earth.com/earthpedia-articles/chimpanzees-vs-bonobos-whats-the-difference/
a bonobo world etc 28: finding connections through difference
some of the language and cultural groups in modern China
Our human world is divided into many nations – 195 or so according to the UN, but this all depends on how you define the term. We know that there are many peoples who see themselves as separate and distinct from the nations they happen to inhabit, and prefer to consider themselves a nation of some sort, and some have named their nation – the Uyghurs of East Turkistan, the Kurds of Kurdistan, the Catalans of Catalonia, the Basques of Cantabria (and many other names) and the Samaritans of Samaria, to name a few – while others, such as the Hazaras, the Rohingyas, the Yorubas and the Tamils, may or may not have specific named territories they would like to claim as their own. In Australia, some have spoken of hundreds of Aboriginal nations, generally associated with language groups. And since we know of about 7,000 existent languages, each associated with particular cultures, there seems to be something of a barrier to any simplistic notions of globalism and global problem-solving.
This is the difference between human apes and other apes. We have divided into distinct groupings, which it seems, our ancestral hominins, going back to CHLCA – the chimpanzee (and bonobo)-human last common ancestor – didn’t do. But is this true? Could it be that the neanderthals and others formed separate cultural groupings within themselves? And how is it that language, which creates such barriers among peoples today, became so diversified as we went forth and multiplied?
Clearly language is a near-unique human capacity. The neanderthals, though, are now known to have possessed a hyoid bone – a horseshoe-like bone in the neck – which may argue for speech capacity. Hyoid fossils have also been found attributed to Homo heidelbergensis and dated back half a million years. If these extinct hominins had language, was it the same language? Language is a means not only of communication but of instilling and handing down cultural praxis, so who knows? The idea of sub-dividing Homo heidelbergensis, Homo neanderthalensis and perhaps others into distinct language and cultural groups really makes the brain spin.
Today, with the greater ease of travel, and with the general tendency of humans, and most other species, to migrate from regions of great danger and few resources to regions of greater resources and fewer dangers, we find that the most economically successful countries are becoming increasingly multicultural, and naturally those countries seek to make a virtue out of necessity.
There are clearly positives and negatives about multiculturalism. Minority cultures understandably seek the comfort of their familiars, leading to ghettoism. They also have vulnerabilities that are exploited by the dominant culture, taking on low-paid or under-the-counter work eschewed by others, and accepting poorer housing and other conditions. Discomfort with difference works both ways of course, and it has been the case that, going back to the days of the early slave-dependent cultures of Greece and Rome, slaves were considered something less than human even by the intelligentsia (and women in somewhat similar ways). The difference today is, or should be, that we know how nonsensical those attitudes were. And yet they persist, in muted form.
There’s also the view, put forward for example by Sam Harris in The moral landscape and, in different form, by David Deutsch in The beginning of infinity, that some cultures are objectively superior than others, especially in terms of law, science and progress. Their general argument is that those cultures that are static or archaic in terms of lore and ideology need to ‘get with the program’ being followed by most developed countries in terms of the pursuit of deeper and richer knowledge and the tools and technologies that flow from that knowledge. And yet, paradoxically, some of that knowledge and research informs us that indigenous cultures in particular, such as existed for tens of thousands of years in Australia, developed practices and technologies over that period which allowed them to live in relative comfort in a landscape that new arrivals from Europe found inherently inhospitable – though of course those new arrivals didn’t by any means give up, and eventually found ways to exploit enough of the land and resources to become populous and dominant.
In reflecting on all these differences and tensions, we need, I think, to always keep in mind how situated we are. None of us chose the cultures we were born into, and this heavy fact should help determine our sympathy for those born into more or less different cultures, as well as those born better or worse off in our own. And there are many features common in our humanity. As a teacher of international English, I’ve taught students from scores of different nations and cultures, and clearly from a range of different positions within those cultures, and I’ve been struck by the broad lines of humanity they share, in terms of humour, ambition, anxiety, desire and wonder. All of these emotions or traits are a kind of human substrate, a permanent foundation upon which human cultures, which come and go and transform and so forth, are constructed, sometimes obscuring the view of the basic humanity that really connects us.
The language barriers may be about to erode, by means of technology – at least the barriers between major languages, such as Mandarin and English (the minority languages will inevitably get the rough end of this particular stick). Electronic translators are a long way from the Babel fish thought up by Douglas Adams in The hitch-hikers guide to the galaxy, a device like Apple’s AirPods which instantly translates every language in the universe into your own, but earpiece translators are already with us, and are bound to improve. It’s surely better than having everyone learn the same, dominant language. But the real promise of this technology is the promise of collaboration, and the reduction of truly artificial, or human-created, differences, and strengthening that human foundation that underlies those differences. Something to hope for.
References
Madelaine Bohme, Rudiger Braun & Florian Breier, Ancient bones, 2020
Human ancestry 2 – a meander through a couple of million years’ time and a world of space
Man is descended from a hairy, tailed quadruped, probably arboreal in its habits.
Charles Darwin
So in this second post I’ll take a little look at Paranthropus and then try to make sense of the move from Australopithecus whateva to Homo whateva, and so on….
There’s a lovely vid about Paranthropus here, which I’ll take much of the following from. There are three known species, P aethiopicus (about 2.7 to 2.3 mya), P boisei (2.3 to 1.4 mya), both only found so far in eastern Africa, and P robustus (2 to 1.2 mya), in southern Africa. They’re all robust species, as opposed to the gracile species A africanus. They have large cheekbones, jaws and teeth, and a prominent sagittal crest across the top of the cranium, a feature shared by gorillas and orang-utangs, and which evolved to attach strong chewing muscles down to the jaw. Apart from these robust characteristics, they shared many features with australopithecines, and have even been defined as robust australopithecines by some. It’s always difficult to split up (or lump together) specimens when only small fragments are found, so there’s a hunt on for more, and bigger, bits and pieces. From what they’ve got, though, it’s estimated that they had a cranial capacity of 475-545 cc, not much more than the average chimp, with a height of about 156cm (just over 5 feet) and a weight of 40-50kg. Smallish perhaps, but I’d be willing to bet they had a pretty impressive muscle to fat ratio. They also appear to have been sexually dimorphic to a greater degree than humans, suggestive of dominant males fighting over females, as in the case of gorillas. There’s also some evidence that the females lacked or had a less prominent sagittal crest.
How are the Paranthropus species related to modern humans? Surprise surprise, we don’t know, and the pathways to and between the various types of Homo just get more complicated. They may simply have died out, as the more recent Neanderthals did. Researchers desperately await more finds, and more techniques for connecting the dots.
So, leaving Paranthropus behind, it’s clear from my last post on the subject that tracing the path from our common ancestor with bonobos (my fave ape) has been a fraught process of speculation and disputation, but of course we have no choice but to keep on trying to trace that path. So, what’s the most recently-lived species of Australopithecus, and the most ancient of the Homo species, as far as we know?
The species A africanus and A sediba seem currently to be in competition to be the immediate ancestor to Homo habilis along the pathway to H sapiens, though there may have been an intermediate, as yet undiscovered, species.
A africanus is known from four sites, all in South Africa, but dating the specimens has been difficult and controversial. The first discovery, the Taung child (1925) is still not clearly dated, and claims for it suffered at the time of its discovery, and for decades afterwards, due to the Piltdown hoax, which I won’t go into here. However, in the mid 1930s the first adult australopithecine was found, and eventually given the A africanus moniker. Evidence of bipedality in this and another adult female, found in 1947, together with evidence of a cranial capacity of about 485 cc for both, was striking evidence that bipedality long preceded brain growth (it has since been mooted as a result of reduced forestation and increased savannah-like environments through climate change, though bipedal traits seem to have existed even before this). A lack of facial projection in these specimens was suggestive of advancement towards modern humanity. And just by the bye, evidence of tool-making among hominins now goes back to 3.4 mya, associated with the A afarensis species. A fourth specimen, ‘Little Foot’, dated to around 3.7 mya, was found in the nineties, but there’s debate about whether it belongs to A africanus or a ‘new’ species, A prometheus (actually suggested by Raymond Dart decades ago). There’s an interesting piece on this here.
I wouldn’t want to be quoted on this, but it seems that the A africanus fossil of a skull now known as ‘Mrs. Ples’ is the most recent A africanus fossil ever found, dated to about 2mya. But what about A sediba? This is the most recently discovered australopithecene, mostly associated with Lee Berger (and his young son), who discovered the first bones in 2008, in South Africa. It has been argued, by its discoverers, to be the most likely transitional species between A africanus and either Homo habilis or H erectus (and it should be noted that many consider H (or A) habilis to be an australopithecine, its placement as Homo being largely based on the use of flaked stone tools, at a time when tool use by australopithecines wasn’t known).
So I think I’ll skip this controversy for now, as I want to get to the more recent radiation of Homo species. Having said that, immediately I start looking at the earliest forms given the Homo moniker, such as H habilis, H erectus and H ergaster, I encounter vast uncertainty and controversy, not to mention my own ignorance. I’ve already discussed H habilis; H ergaster (1.9 to 1.4 mya), according to Wikipedia, ‘is now mostly considered either an early form, or an African variety, of H erectus‘. Oh dear, I thought H erectus was African!
In fact, the first fossils identified with H erectus were found in Eurasian Georgia and in China, but the species may have back-migrated to Africa. Or maybe not. I’m on the verge of giving up here, but I’ll extricate myself from the mess by listing and briefly discussing the various forms of Homo that have been postulated. These aren’t necessarily in chronological order.
- H habilis (approx 2.1-1.5mya) – short but with longer arms compared to modern humans, with a cranial capacity of around 700 cc. Used stone tools. Relatively robust, compared to H ergaster. Contested classification. Probably co-existed with H erectus. Only found in Africa.
- H ergaster (approx 1.9-1.4mya) – I’ve used the Wikipedia existence range here, but the Australian museum suggests that arguments about existing classification of specimens may extend that range up to 700,000 ya. They also point out that some don’t accept this classification at all, preferring H erectus. They were relatively hairless and more closely resembled modern humans than earlier types. Possible specimens found in modern Kenya, Ethiopia, South Africa, and most notably in Georgia (Eurasia), which suggests first emergence of early humans from Africa occurred about 1.7mya. Cranial capacity, about 860cc .
- H erectus (approx 1.8mya- 100,000ya?) – first found in Java, other specimens found in Indonesia, China and Africa. Short and stocky with heavy brow ridges. Sometimes hard to separate from H ergaster, especially the African specimens. H erectus is now more widely believed to be a side-branch, and H ergaster our more direct, if more ancient, ancestor. Cranial capacity about 1050cc.
- H rudolfensis (approx 2.4mya- 1.8mya) – specimens found in modern Malawi and Kenya. A contested classification, could be lumped in with H habilis. There is always a difficulty when dealing with limited specimens, which might be atypical, juvenile or of unknown gender. Anyway, estimated cranial capacity, about 750cc. Size and shape insufficiently known.
- H heidelbergensis (c700,000-300,000 ya) – evolved in Africa, but in Europe by 500,000 ya (African fossils are mostly older). Lived and worked in co-operative groups, using a variety of tools. Specimens found in England, France and Spain as well as in the region of Heidelberg, Germany. Possibly as far east as northern India. Also in Zambia and South Africa. Physically tall, up to 180 cms, suggesting descent from H ergaster. Brain capacity approx 1250cc.
- H neanderthalensis (?800,000-40,000 ya) – some have argued that they were around as recently as 28,000 years ago. The first fossil was found in the 1820s, and was the first fossil of any extinct hominin ever found. Their cranial capacity, at 1500cc, is larger than that of H sapiens, not surprisingly due to their larger overall build (shorter but much more solid). No specimens found as yet in Africa, but a large number of finds throughout Europe and the Middle East (and possibly in China) allow us to build a clearer picture of Neanderthals than any other extinct hominin. They used a variety of tools, which they may have obtained through trade with modern humans. They wore animal hides and used fire for warmth, cooking and protection. Physically they were thickset, with heavy brow ridges and a relatively receding forehead, a forward-projecting face, a large, broad nose, and strong neck muscles. It’s now known, of course, that they interbred to some degree with modern humans, but it’s also likely that they competed with them for scarce resources, especially during ice ages. Though we don’t now consider them to be ‘nasty, brutish and short’ it may well be that the greater resourcefulness of H sapiens hastened their demise.
- H rhodesiensis (c800,000-120,000 ya) – now generally seen as an African subspecies of H heidelbergensis, with specimens found in Rhodesia/Zambia, Ethiopia and Tanzania.
- H cepranensis (c900,000-800,000 ya) – based on one fossil skull cap, or calvaria, unearthed near Ceprano, Italy in 1994. Others are for H heidelbergensis. The dating is also highly contested, with some arguing for around 450,000 ya. There’s probably quite a few more of this sort – but every new find is exciting.
- H denisova (? – 15,000 ya) – This isn’t an agreed taxonomic title, but the Denisovan finds are certainly exciting, with mitochondrial DNA being recovered from the first find (in a Siberian cave), the finger-bone of a juvenile female (how do they know that??). Other specimens have been found in the same cave, and another has been found in Tibet. There’s not enough material for us to picture this species, but the DNA tells us that they interbred with Neanderthals, and to a lesser degree with Melanesians, Papuans and Aboriginal Australians.
- H floresiensis (c190,000-50,000 ya) – found only on the Indonesian island of Flores. Another exciting, and puzzling, recent find. Could they have been killed off by those passing though on their way to Australia? Researchers are still hoping to recover mitochondrial DNA from the most recent specimens. Physically, these were unique humans with a very small stature and a cranial capacity of 380cc (chimp size), though with an enlarged Broadman area 10, which is associated with complex cognitive abilities. Other skull features, though, suggest a primitiveness going back more to H erectus. Tools found at the site have raised controversy. Do they belong to H floresiensis? They don’t easily equate with such a small brain. There is no precedent. Much still to be learned.
So I’ve raised far more questions for myself than I’ve answered. Hope to come back to this topic in future, with a focus on bipedality, climate effects, the beginnings of ‘culture’, and migration, among other things.
References
https://australianmuseum.net.au/learn/science/human-evolution/ (a great site, with links to details on particular species)
Paranthropus evolution (video), by Stefan Milo, 2019
https://en.wikipedia.org/wiki/Australopithecus
https://en.wikipedia.org/wiki/Australopithecus_africanus
https://en.wikipedia.org/wiki/Australopithecus_sediba
https://en.wikipedia.org/wiki/Homo_ergaster
http://humanorigins.si.edu/evidence/human-fossils/species/homo-habilis
modern humans are getting less modern, in unexpected places
Taken from the website of Science magazine
In recent years we’ve been almost overwhelmed by paleontological discoveries (and re-analyses of earlier discoveries), from giant worm jaws to a new subclass of cephalopod to a new semi-aquatic non-avian dinosaur to the oldest fossils yet found of that strange species, Homo sapiens.
I’ve decided to focus on the last example, for now. Homo sapiens fossils discovered at Jebel Irhoud in Morocco in the sixties, and long thought to have been some 40,000 years old, came under increasing ‘suspicion’ from palaeontologists, beginning in the eighties, due to various curious anomalies. More intensive searching at the Jebel Irhoud site recently has led to a wealth of discoveries, ‘including skull bones from five [human-like, though with a different brain-case, especially at the back] individuals who all died around the same time’. And thanks to the new thermoluminescence dating technique, which is applied to heated or burned substances (it’s a measure of accumulated radiation), a date of 300,000 years was calculated for the tools found near the fossils, and by association for the fossils themselves. This makes them over 100,000 years older than those found in Ethiopia. The Ethiopian fossil discoveries gave rise to the idea that ‘modern’ humans began life in a small region of East-Central Africa and gradually spread, but the revelation about the Moroccan fossils means a revision, or overturning, of that hypothesis.
You’ll notice I’ve put modern in skeptical quotes. It seems to me nobody will agree on what a modern human really is, or whether it’s decided entirely on anatomical or physiological features. If you found yourself suddenly transported to the days of Sargon and the Akkadian civilisation, only 4,500 years ago, you probably wouldn’t have the impression you were living among modern humans – depending on how prepared you were for the culture shock. Of course, paleontologists would have different measures for modernity – brain size, skeletal features and such – but these are necessarily imprecise given individual variation and the sparsity of really good fossils. And there’s also the matter of incremental, barely discernible change. For example, our 300,000-year-old Jebel Irhoud specimens are, perhaps, the oldest known modern human specimens, but it would be silly to argue that their parents weren’t just as modern – and what of their grandparents? And in this way we can go back another 10,000 years, or maybe 50,000, without seeing much difference. This has always been the most difficult thing to get my head around, not only for H sapiens but for any species. When does Australopithecus afarensis start/stop being Australopithecus afarensis? When did a chimp distinguish herself from a bonobo, and when did they both get differentiated from their predecessor? Are we taking hard and fast taxonomy too seriously? Maybe I’ll return to that some time…
Meanwhile, another recently revealed discovery has added to the ‘out of Africa’ confusion, which many thought was becoming less confused, with something like a consensus that H sapiens emerged from Africa between 70 and 100 thousand years ago and dispersed globally, with the oldest Australian human possibly dating back as far as 65,000 years.
The discovery of a human jawbone and teeth in Israel that date back nearly 200,000 years has messed up that simplifying story, and it’s only one of a number of finds that are making the experts get confused – and excited – again. The jawbone find, combined with sophisticated tools and weaponry, is solid evidence of H sapiens coming out of Africa much earlier, and perhaps on an irregular basis depending on climatic conditions and resources. Human teeth found in China, and human fossils in Sumatra, dating to at least 70,000 years ago, tend to confirm this hypothesis. Other fossil discoveries in Israel are complicating the picture. The Eastern Mediterranean seems to have been a crossroads where various early human species may have interacted.
These new discoveries appear to confound the genetic evidence that we’re all related to an out-of-Africa population that emerged well under 100,000 years ago, but it seems these early populations died out or returned to Africa.
Yet there are so many mysteries still to solve. What about the strange Denisovans? We have so little fossil evidence, yet enough to map almost the entire nuclear and mitochondrial genome – a testament to modern technology. Analysis of their mtDNA suggests that they migrated out of Africa much earlier than the modern humans above-mentioned, but later than H erectus. They apparently branched off from the human line 600,000 years ago, and from Neanderthals about 400,000 years ago. The fullness and fascinating richness of the Wikipedia article on the Denisovans, garnered from such minute fossil evidence, is a source of great wonder to me. The specimens (of four distinct Denisovans) were well preserved due to the icy temperatures in the Siberian cave, near the Mongolian-Chinese border, where they were found. The finger bone, dated to about 40,000 years BP (Before Present, a new designation to me, and a welcome one), has yielded both mitochondrial and nuclear DNA, which has shown the Denisovans to be distinct from both Neanderthals and modern humans, and that they share a common ancestor with Neanderthals. Other excavations of the cave show that it was inhabited at least 125,000 years ago. mtDNA analysis has apparently revealed that the three, H sapiens, Denisovans and Neanderthals, shared a common ancestor about 1 million years ago. I’m writing these facts, if they are facts, as I find them, while wondering what they mean, and especially how the evolutionary tree can be visualised, but it’s pretty difficult, especially when you consider interbreeding. Looks like I’ll have to write and do the research for half a dozen posts before I start to get it straight in my own head. Anyway, here’s one interesting chart I’ve found.
There are clearly more mystery hominids to be found, to fill out the complicating picture. And of course I’ve mentioned the genetics and genomics only in passing, but again it’s astonishing what they can find these days by comparing these genes with what we know of some modern human populations. For example, studies of the Denisovans genome found ‘a region around the EPAS1 gene that assists with adaptation to low oxygen levels at high altitude’, already known from analysis of modern Tibetan genes.
Hoping to keep myself up to date with all this, if I don’t get too distracted by the zillions of other fields of enquiry worth keeping up with…
References
https://en.wikipedia.org/wiki/Denisovan
All the excitation about Trump having tried to sack Mueller annoys me because it makes me – well, too excited. I have to learn to be patient. The Mueller enquiry will end when it does, and it’s sure to end dramatically. Still, I hunger for another indictment, or equivalent headline. One point worth worrying about though, is what happens when Trump goes? The whole administration should go, but that’s not what happens in the US. No snap elections, no double dissolution. Another weakness of the Presidential system, it seems to me. In the US, you vote for a personality, and that personality gets to build a team around him (it’s always been a bloke), whereas in most advanced western nations, the country’s leader has risen through the ranks of the team, much like the captain of a soccer team, who’s given the captain’s armband, not because she’s the best player – though she quite often is – but because she’s the most inspiring leader. If that captain falls afoul of the law, another competent team member can take on the job. In the case of the US Presidency, the team is tainted by the captain’s failings because he’s personally chosen the lot of them – in this case largely because of their political ignorance, which he regards as a positive.
When was the first language? When was the first human?
Reading a new book of mine, Steven Pinker’s The sense of style, 2014, I was bemused by his casual remark on the first page of the first chapter, ‘The spoken word is older than our species…’. Hmmm. As Bill Bryson put it in A short history of nearly everything, ‘How do they know that?’. And maybe I should dispense with ‘they’ here – how does Pinker know that? My previous shallow research has told me that nobody knows when the first full-fledged language was spoken. Furthermore, we’re not sure about the first full-fledged human either. Was it mitochondrial Eve? But what about her mum? And her mum’s great-grandad? Which raises an old conundrum, one that very much exercised Darwin, and which creationists today love to make much of, the conundrum of speciation.
Recently, palaeontologists discovered human-like remains that might be 300,000 years old in a Moroccan cave. Or, that’s the story as I first heard it. Turns out they were discovered decades ago and dated at about 40,000 years, though some of their features didn’t match with that age. They’ve been reanalysed using thermoluminescense dating, a complicated technique involving measuring light emitted from escaping electrons (don’t ask). No doubt the dating findings will be disputed, as well as findings about just how human these early humans – about 100,000 years earlier than the usual Ethiopian suspects – really are. It’s another version of the lumpers/splitters debate, I suspect. It’s generally recognised that the Moroccan specimens have smaller brains than those from Ethiopia, but it’s not necessarily the case that they’re direct ancestors, proof that there was a rapid brain expansion in the intervening period.
Still there’s no doubt that the Moroccan finding, if it holds up, is significant, as at the very least it pushes back findings on the middle Stone Age, when the making of stone blades began, according to Ian Tattersall, the curator emeritus of human origins at the American Museum of Natural History. But as to tracing our ancestry back to ‘the first humans’, we just can’t do this at present, we can’t join the dots because we have far too few dots to join. It’s a question whether we’ll ever have enough. Evolution isn’t just gradual, it’s divergent, bushy. Where does Homo naledi, dated to around 250,000 years ago, fit into the picture? What about the Denisovans?
Meanwhile, new research and technologies continue to complicate the picture of humans and their ancestors. It’s been generally accepted that the last common ancestor of chimps and humans lived between 5 and 7 million years ago in Africa, but a multinational team of researchers has cast doubt on the assumption of African origin. The research focused on dental structures in two specimens of the fossil hominid Graecopithecus freybergi, found in Greece and Bulgaria. They found that the roots of their premolars were partially fused, making them similar to those of the human lineage, from Ardepithecus and Australopithecus to modern humans. These fossils date to around 7.2 million years ago. It’s conjectured that the possible placing of the divergence further north than has previously been hypothesised has much to do with environmental factors of the time. So, okay, African conditions were more northerly in those days…
So these new findings and new dating techniques are adding to the picture without clarifying it much, as yet. They’re like tiny pieces in a massive jigsaw puzzle, gradually accumulating, sometimes shifted to places of better fit, and so tantalisingly offering new perspectives on what the whole history might look like. I can imagine that in this field, as in so many others, researchers are chafing against their own mortality, as they yearn for a clearer, more comprehensive future view.
Meanwhile, speculations continue. Colin Barras offers his own in a recent New Scientist article, in which he considers the spread of H sapiens in relation to H naledi and H floresiensis. The 1800 or so H naledi fossil bones, discovered in a South African cave four years ago by a team of researchers led by Lee Berger, took a while to be reliably dated to around 250,000 years (give or take some 50,000), just a bit earlier than the most reliably dated H sapiens (though that may change). Getting at a precise age for fossils is often difficult and depends on many variables, in particular the surrounding rock or sediment, and many researchers were opting for a much earlier period on the evidence of the specimens themselves – their small brain size, their curved fingers and other formations. But if the most recent dating figure is correct (and there’s still some doubt) then, according to Barras, it just might be that H sapiens co-existed, in time and place, with these more primitive hominids, and outcompeted them. And more recent dating of H floresiensis, those isolated (so far as we currently know) hominids from the Indonesian island of Flores, has ruled out that they lived less than 50,000 years ago, so their extinction, again, may have coincided with the spread of all-conquering H sapiens. Their remote island location may explain their survival into relatively recent times, but their ancestry is very much in dispute. A recent, apparently comprehensive analysis may have solved the mystery however. It suggests H floresiensis descended from an undiscovered ancestor that left Africa over 2 million years ago. Those who stayed put evolved into H habilis, the first tool makers. Those who left may have reached the Flores region more than 700,000 years ago. The analysis is based on detailed comparisons with many other hominid species and earlier ancestors.
I doubt there will ever be agreement on the first humans, or a very precise date. We’re not so easily defined. But what about the first language? Is it confined to our species?
Much of the speculation on this question focuses on our Neanderthal cousins as the most likely candidates. Researchers have examined the Neanderthal throat structure as far as possible (soft tissue doesn’t fossilise, which is a problem), and have found one intriguing piece of evidence that makes Neanderthal speech plausible. The semi-circular hyoid bone is located high in the human throat, and is found in the same place in the Neanderthal throat. Given that this bone is differently placed in the throat of our common ancestors, this appears to be an example of convergent evolution. We don’t know the precise role of the hyoid in speech, but it certainly affects the space of the throat, and its flexible relationship to other bones and signs of its ‘intense and constant activity’ are suggestive of a role in language. Examination of the hyoids of other hominids suggests that a rudimentary form of language may go back at least 500,000 years, but this is far from confirmed. It’s probable that language underwent a more rapid development between 75,000 and 50,000 years ago. It’s also worth noting that a full-fledged language doesn’t depend on speech, as signing proves. It may be that a more or less sophisticated gestural system preceded spoken language.
a selection of primate hyoid bones
Of course there’s an awful lot more to say on the origin of language, even if much of it’s highly speculative. I plan to watch all the best videos and online lectures on the subject, and I’ll post about it again soon.
References
https://www.sciencedaily.com/releases/2017/05/170523083548.htm
https://www.vox.com/science-and-health/2017/6/7/15745714/nature-homo-sapien-remains-jebel-irhoud