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a bonobo world, etc 17 – good and bad hierarchies, human superiority and extinction threats

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Robert Sapolsky on hierarchies – always worth listening to

One might say that bonobo society isn’t democratic, it’s hierarchical. But of course being hierarchical isn’t the opposite of being democratic. Every human society has been and is hierarchical. The hierarchy in earliest human times was probably based on raw prowess in providing resources and maintaining effective order in the group, the tribe, the village. Whoever managed to do so obtained prestige for himself, his family or breeding partners and his heirs, until such time as it all fell apart and competitors proved more effective. History, some former toff wrote, is a graveyard of aristocracies, but as human society became more formalised, those aristocracies often survived beyond their utility (to everyone but the aristocratic clique), as witness various hereditary power systems. Arguably the most unequal and rigid hierarchies were based on land ownership and control, when societies were largely agricultural, in feudal Europe and no doubt elsewhere. The more one family was able to concentrate power in its hands, as in medieval Britain and Czarist Russia, the more steps there would be in the ladder to the bottom, where the majority slaved away. 

Nowadays, of course, we’re more slaves to our devices than to any human overlords. Most of us have never seen a harvest, but our homes are full of fruits and wines, basics and treats. Where our ancestors were treated as little more than effluent, we now feel ourselves to be relatively affluent, even with part-time work in service or tech industries. Where our forebears worried about the breadline, we’re more concerned about our waistline, and where we’ll put all our stuff. In his indispensable book The origin of feces (I had to buy it), David Waltner-Toews points out that, with some 7.5 billion human apes on the planet, we’re producing over 400 million tonnes of shit per year. Add to that our ever-increasing loads of sheepshit, bullshit, horseshit and chickenshit, and the figures for these are as mucky as the topic, and you might start to worry whether it’s the effluent of affluence that will finally bury us. 

However, the prospect of spaceship Earth gradually filling up with the brown-and-yellow, or any other stuff, shouldn’t concern us, not because it’s all more or less biodegradable, but because spaceship Earth is just a bad metaphor, according to David Deutsch in The beginning of infinity. For Deutsch, the problem with the metaphor is its emphasis on finite resources, finite space, finite everything, and the idea that we humans are abusing the spaceship’s finite ‘design’. Deutsch is a boundless admirer of Jacob Bronowski and his 70s series ‘The ascent of man’, by which he means we human apes. Basically, Deutsch and Bronowski share the vision of a Danish prince written about some centuries ago: 

What a piece of work is a man! How noble in reason, how infinite in faculty! In form and moving how express and admirable! In action how like an angel, in apprehension how like a god! The beauty of the world. The paragon of animals.

There seems to have been a bit of sarcasm at play there, but Deutsch is very much an optimist about human capacities, as his book’s title implies. The ascent of human apes isn’t like an ascent to the mountain’s summit, even less up the stairway to heaven, it’s the rise and expansion into a human-created infinity of invention and creation – a forever bubble blown out of human ingenuity, as progress accelerates and earth-boundness becomes hide-boundness and shit turns to sugar through the magic of science that is not magic.

And yet there are still human hierarchies, on an individual and even a national level. There are the OECD nations, for example, and those who don’t make the grade. There are the G8 or G7 nations and the not-so G7 nations. And there are the stateless and the non-nationalists, who might sometimes wish they were bonobos. Or would if they only knew… 

Meanwhile, bonobos, hierarchical but also inclusive. Huddled together lovingly, mostly, and besieged, perhaps without knowing it. Did the last Neanderthals, perhaps huddled together in Gibraltar’s caves, know, or have any inkling, that they were the last? The African Wildlife Foundation (AWF) describes bonobos as Africa’s forgotten ape. Many people I know hadn’t even heard of them. It might well be their remoteness, compared to chimps. The southern bank of the Congo bears little resemblance to la rive gauche of Paris, and long may it remain so, but for years the region has been threatened by human warfare, slash and burn agriculture, and bushmeat hunting. The current wild population is hard to assess, but it is at least larger than perhaps the smallest ethnic group of humans, the Samaritans, who number less than a thousand. The Samaritans, however differ from bonobos in that their numbers are very gradually rising, without the need for them to be protected in zoos. Bonobos also manage to be charitable without religion. 

Truly the threats to the bonobo community are no laughing matter, and I hope in my way to provide them with a pinch more of publicity. There’s competition of course. The solitary orang-utans of Sumatra and Borneo are under severe threat from deforestation and palm oil production, and Madagascar’s unique biodiversity is being devastated, again by slash and burn agriculture, as well as mining, climate change, invasive species, overharvesting and habitat fragmentation. Andy Isaacson writes about it in Cosmos magazine: 

Madagascar’s endemic lemurs are now the most threatened group of primates on Earth, and nearly all of its species (94%) are at risk of extinction because of habitat loss and unsustainable hunting. 

As always, there are human heroes, local and international, struggling to protect and improve the lives of these cousins of ours. Bonobos are facing an upsurge of hunting, according to AWF’s Jacqueline Conciatore:

For a long time, local taboos against hunting bonobos, who are so human-like, protected the peaceable apes. But those mores are dropping off under the influence of cultural outsiders and with tradition’s weakening hold on the young. Today, commercial bushmeat hunting, supported by ever more trade routes, joins habitat loss as a top threat to bonobos. Some researchers estimate that tons of bushmeat are extracted daily in bonobo range areas. The number of bonobos killed for bushmeat is limited compared to other species, but because bonobos reproduce slowly, bushmeat hunting poses a dire threat.

Spaceship Earth may seem ever-expandable for the all-conquering, infinitely capable human ape, and of course I accept that we aren’t under threat here in the way that the Ehrlichs’ book The Population Bomb notoriously predicted, but it’s notable that David Deutsch makes no mention of the plight of other species, let alone other apes, in his book about the future. Perhaps we can do without them?

References

https://www.awf.org/blog/endangered-bonobo-africas-forgotten-ape#:~:text=Bonobos%20battle%20bush%20meat%20hunting%20and%20shrinking%20habitats&text=Throughout%20their%20range%2C%20bonobos%20are,15%2C000%2D20%2C000%20wild%20bonobos%20remaining.

https://en.wikipedia.org/wiki/Neanderthals_in_Gibraltar#:~:text=Gibraltar’s%20Neanderthals%20may%20have%20been,Neanderthal%20populations%20elsewhere%20in%20Europe.

https://en.wikipedia.org/wiki/Samaritans#Demographics

Andy Isaacson, ‘Food to save Madagascar’s future’, in Cosmos, issue 88

David Waltner-Toews, The origin of feces, 2013

David Deutsch, The beginning of infinity, 2011

Written by stewart henderson

December 17, 2020 at 8:15 pm

Human ancestry 2 – a meander through a couple of million years’ time and a world of space

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Man is descended from a hairy, tailed quadruped, probably arboreal in its habits.

Charles Darwin

Homo neanderthalensis, with a very bad toothache

 

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.

  1. 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.
  2. 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 .
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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

Written by stewart henderson

October 30, 2019 at 9:59 pm