Everything One Needs to Know about Palaeoanthropology, Some of
which you can’t get from Wikipedia (a “Monograph” in the Style of Spike
Milligan)
The story of palaeoanthropology begins when the homo genus begins…
Or it would, if this weren’t a vexed question. Truth is it’s hard to say when
the story begins.
One might have thought the obvious place to
begin our story would be the “Chimpanzee Human Last Common Ancestor (CHLCA)”. Alas,
anyone who might have thought this is ignorant, since the “Chimpanzee Human
Last Common Ancestor” is not known! [1]
The attempt to pinpoint the CHLCA is
seriously complicated by the fact that hybridisation between species belonging more
distinctly to either the “Homo” or the “Pan” genus lasted until perhaps 4
million years ago. In any case, the idea of a Last Common Ancestor is actually
a way sexy idea than it maybe first appears. It becomes less cool, I think,
when you reflect more deeply on how genetics works throughout massive stretches
of time – recognising for example, that the last common ancestor between two
phylogenetic trees moves back as we move back in time (the common ancestor between
Homo erectus and the ancient chimp ancestors contemporaneous with it would have
been probably a fair bit farther back in history than the CHLCA), or
recognising the fact that the CHLCA, ‘whoever’ it was, is only infinitesimally
closer to us genetically than its contemporaries and in that sense not super
‘special’ (this schematic diagram of Mitochondrial
Eve’s relationship to us marginally helps in getting your head around the
idea of a last common ancestor way back in the past: https://en.wikipedia.org/wiki/Mitochondrial_Eve#/media/File:MtDNA-MRCA-generations-Evolution.svg).
Anyhow, the following Wikipedia page is
a lapidary review of the research on the CHLCA, and the difficulties
surrounding this research topic: https://en.wikipedia.org/wiki/Chimpanzee–human_last_common_ancestor
(Wikipedia is a pretty good source for palaeoanthropology nowadays, with proper
sourcing and useful hyperlinked phylogenetic trees and the like. It’s a really
excellent recent development. I cannot be made to feel embarrassed about using
Wikipedia as a major source on this shit, because it’s really good.).
It’s worth mentioning that some people say
dodgy shit involving this phrase “Chimpanzee Human Last Common Ancestor” –
usually, dodgy shit of the epistemically arrogant kind (suggesting that we know
more than we in fact do). For example, I am told that this tiny-brained,
probably-not-bipedal species from 7 million years ago (https://en.wikipedia.org/wiki/Sahelanthropus),
is often called the last Chimpanzee Human Last Common Ancestor (we note here
that people sometimes use this word “ancestor” to mean ancestral species, which
certainly confuses matters in this context). The truth is we (by which I mean
people who are actually experts in these topics) have no idea whether there is
another more recent species some of whose members are common ancestors to
humans and chimps. My research suggests that the rational attitude to hold
would be that there probably is,
since there are plenty of proto-hominin and proto-pan species from this vintage
which are lost to time! Here’s a disturbing fact: we will never learn anything about
99+% of the big interesting creatures that have ever existed (let alone the
small uninteresting ones), because we will never uncover any evidence that
testifies to their existence.
Personally, I don’t really give a shit about
chimpanzees; I am way more interested in the uncanny-valley creatures that
clearly couldn’t be classified within the “Pan” genus and have skulls larger
than the piddling 320-380cm3 of the Sahelanthropus tchadensis. The next two
species in our timeline don’t really have very big brains, but at least they’re
distinctly more “Homo” than “Pans”. I am here talking about the two species
we’ve found[2]
that we’ve decided to classify as members of the Ardipithecus genus, “A. ramidus, which lived
about 4.4 million years ago[2] during the early Pliocene, and A. kadabba, dated to
approximately 5.6 million years ago (late Miocene)”. Now, once again, the Wikipedia article on
this genus is actually much more useful than me (this will not be the case
nearly so much when it comes to Homo erectus and beyond, which constitutes one
of the two reasons why it is not completely pointless for me to write this
engaging monograph; the other is that I make you laugh) so I would recommend
you consult that now: https://en.wikipedia.org/wiki/Ardipithecus. Obviously, even though this Wikipedia article possesses much more
information on this genus than I can provide (even after having read it myself,
because I don’t have an eidetic memory ☹) I can still also intelligently draw attention to
the most interesting extracts from this article and analyse them in the context
of my extensive auxiliary knowledge. Here is the part of the article where the
things that make this genus non-chimpanzee-like are discussed, which I find
particularly interesting:
“The teeth of A. ramidus lacked the specialization of other apes, and suggest that it was a generalized omnivore and frugivore (fruit eater) with a diet that did not depend heavily on foliage, fibrous plant material (roots, tubers, etc.), or hard and or abrasive food. The size of the upper canine tooth in A. ramidus males was not distinctly different from that of females. Their upper canines were less sharp than those of modern common chimpanzees in part because of this decreased upper canine size, as larger upper canines can be honed through wear against teeth in the lower mouth. The features of the upper canine in A. ramidus contrast with the sexual dimorphism observed in common chimpanzees, where males have significantly larger and sharper upper canine teeth than females.[9]
“The teeth of A. ramidus lacked the specialization of other apes, and suggest that it was a generalized omnivore and frugivore (fruit eater) with a diet that did not depend heavily on foliage, fibrous plant material (roots, tubers, etc.), or hard and or abrasive food. The size of the upper canine tooth in A. ramidus males was not distinctly different from that of females. Their upper canines were less sharp than those of modern common chimpanzees in part because of this decreased upper canine size, as larger upper canines can be honed through wear against teeth in the lower mouth. The features of the upper canine in A. ramidus contrast with the sexual dimorphism observed in common chimpanzees, where males have significantly larger and sharper upper canine teeth than females.[9]
The less pronounced nature of the upper canine
teeth in A. ramidus has been used to infer aspects of
the social behavior of the species and more ancestral
hominids. In particular, it has been used to suggest that the last common ancestor of hominids and
African apes was characterized by relatively little aggression between males
and between groups. This is markedly different from social patterns in common
chimpanzees, among which intermale and intergroup aggression are typically
high. Researchers in a 2009 study said that this condition "compromises
the living chimpanzee as a behavioral model for the ancestral hominid
condition."”
As you journey through this monograph (this
word elevates what will really turn out to be a madcap ramble), you’ll notice
that one of the key themes of palaeoanthropology is what an idiot might term the magic of teeth. Stripping away the
dumb jokes (enamel) from this sentence, the hard calcium core of what I’m
saying is simply this: teeth can tell you a lot. … Incidentally, my grandpa was
a dentist. He died in 2014 but his genes (which are, sadly, mildly degenerate
in that they seem to be associated with a really shitty nose phenotype and a
proneness to going deaf, even if they are also associated with intelligence
(both sides of my family are high-intelligence, which explains my cosmic intellect))
live on. A Homo sapiens man continuing the line going back 200-350,000 years… Reely
maeks u think.
Returning to the science (said with snooty, shade-throwing emphasis
by the grumpy, middle-aged superego-version of me), it is super interesting that although these Ardipithecus monsters
were probably not bipedal, the teeth (and the diminished sexual dimorphism)
suggest to us that they were not living a chimpanzee-style lifestyle, and that
their menfolk were acting slightly less like Clint Eastwood and more like
Michael Cera (I normally go for higher-brow references but maybe this joke will
bring in the masses, and I can set up a Patreon). I mean, we shouldn’t
exaggerate on this point; I mean, I didn’t
(I said “slightly”), what I’m really saying is you shouldn’t exaggerate on this point. Don’t do it, asshole! But
it is interesting. To me. I don’t presume.
Actually, fuck these Ardipithecus idiots. They
were still microcephalic as fuck. If you saw one in the wild, your folk biology
wouldn’t have any trouble classifying it as very much “an animal”. When we’re
talking about this genus, we’re still way back at 4 million years here; we’re
not quite in the uncanny valley. The question is: where do we go for some
unambiguously hominin[3]
action?
Answer: we can stay in the Pliocene to find
the late Australopithecines (I used
the qualifier “late” because some people use the word Australopithecines to encompass even the species I just mentioned
apparently)! Australopithecus afarensis, the Australopithecus which we know
most about (perhaps living between 3.9 million and 2.9 million years ago (late
Pliocene, basically)), is most definitely a hominin, with a bigger brain than
the Ardipithecines (though still only 380-430 cm3) and a definitely
bipedal gait (maybe not fully upright and possibly spending a fair amount of
time in trees, however, especially judging by the curvature of the “phalanges”
and the ‘wrist-locking’ mechanism), as well as a plurality of other exciting
properties. It may well be a direct ancestor of us.
As the (again) excellent Wikipedia page for
this species notes (https://en.wikipedia.org/wiki/Australopithecus_afarensis),
we have given a name to our most complete Australopithecine fossil: “Lucy”. This
Wikipedia page also has loads of really interesting anatomical analysis giving
the reasons why we are highly confident that Lucy and her conspecifics were
bipedal. Probably the biggest thing that sticks out about Lucy’s skeleton in contrast
with a chimp female’s is her wide hips, and one of the things that is noted in
the article is that the hips of late Australopithecines were very human-like.
The pelvis and happens had to change to be more ‘human-like’ very early on in
our evolutionary story, because bipedalism couldn’t happen without a big change
in the pelvis!
One of the major interesting questions raised
in the Wikipedia article is this: what
were the evolutionary pressures that forced the evolution of bipedalism? The
article explains the basic theory well: “Climate
changes around 11 to 10 million years ago affected forests in East and
Central Africa, establishing periods where openings in forest lands prevented
travel through the tree canopy. During such times proto-hominins could
have adopted upright walking behaviour for ever-increasing ground travel, while
the ancestors of gorillas and chimpanzees continued to specialize in climbing
vertical tree trunks and lianas with a bent-hip and bent-knee posture—which
ultimately lead them also to adopt knuckle-walking for minimal ground travel.
This differential development within the larger hominid community would result
in A. afarensis being adapted to upright bipedalism for
extensive ground travel while still using arms well adapted for climbing
smaller trees.”
It's not a hugely sexy story, unfortunately.
Climate changes really thinned out forests in certain areas, perhaps creating
savannah-type areas. The niche of the proto-hominins gradually became thinly
forested areas… And gradually the skeleton changed.
Less well-known than “Lucy” is this fossil, https://en.wikipedia.org/wiki/Kenyanthropus,
dating from a slightly later period, and known by the rather comic moniker
“Flat-faced man”. As the start of this Wikipedia page explains, there are
disputes over whether this fossil should be given its own species name, or
whether perhaps it belongs to its own genus (or neither). The main notable thing about this fossil is that it was found near
stone tools dating from a similar period which gives us reason to think that ‘its
kind’ may have been one of the first stone-tool-using kinds. Another notable
thing about the fossil was its humanlike facial morphology. As Wikipedia puts
it, “Kenyanthropus
platyops was
singled out by the morphology of the maxilla, characterized by a flat and
relatively orthognathic subnasal region, an anteriorly placed zygomatic process
and small molars. In other words, the Kenyanthropus had small
molars and a flat face which resembled anatomically modern humans.” The phrase
“orthognathic subnasal region” may be opaque to the average person but
basically what it means is that this creature didn’t look really chimp-like in
having a face where the mouth really protrudes a lot. This is a pretty darned
fascinating feature of the fossil! Again, we see that teeth can tell you a lot,
and that diet seems to have been very significant in driving the evolution of
hominins. Of course, the skull size of this species seems to fit well within
the Australopithecus range, so its intelligence was nothing to write home
about… but life isn’t all about intelligence, is it? Clearly not.
Shit really
gets interesting in the very late Pliocene/very early Pleistocene (Paleolithic),
because it is in this period that the Homo genus enters the scene.
Specifically, it in this period that the first Homo species enters the scene in
the form of Homo habilis (“handy
man”).[4] The so-called “type specimen” (https://en.wikipedia.org/wiki/OH_7) of this wonderful species was
discovered way back in 1960 in that most fertile of fossil troves, the Olduvai
Gorge of Tanzania (part of the famous Rift Valley), by a mother and son team by
the name of “Leakey” (find out more by clicking that Wikipedia link – the
Leakeys were an amazing family). Anyhow, I’m just going to do that distasteful
thing of copying a section from this Wikipedia page to give a nice summary of
the key properties of this specimen that gave palaeoanthropologists such
confidence that they ought to create a new species category to place it in:
“The remains
are dated to approximately 1.75 million years, and consist of fragmented parts
of a lower mandible (which still holds thirteen teeth, as well as unerupted
wisdom teeth), an isolated maxillary molar, two parietal bones, and twenty-one
finger, hand, and wrist bones.[2]
The OH 7 hand
is wide, with a large thumb and broad fingertips, similar to that of humans;
however, unlike in humans the fingers are relatively long and exhibit
chimpanzee-like curvature. Furthermore, the thumb's orientation relative to the
other fingers resembles the anatomy of great apes.[3] The parietal bones — a nearly complete left parietal
and fragmented right parietal — were used to deduce the cranial capacity of the
hominid, which was placed at 663 cc in account of the fact that the fossils
belonged to a 12- or 13-year-old male. This was extrapolated by Phillip Tobias to 674 cc for the hominid's full adult potential.[4] However, other scientists have estimated the cranial
capacity at 590 cc[5] to 710 cc.[6]
Louis Leakey, John Napier, and Phillip Tobias were among the
first to extensively study the fossils. The Leakey team and others argued that,
due expanded cranial capacity,[4] gnathic reduction, relatively small
post-canine teeth (compared to Paranthropus boisei),[7] Homo-like pattern of craniofacial development,[8] and a precision grip in the hand fragments (which
indicated the ability for tool use), set OH 7 apart as a transitional species between Australopithecus
africanus and Homo erectus.”
Again, we
notice the focus on orthognathism as a sign of modernity, and orthognathism
going along with a reduction in the molar teeth. The skull size of Homo habilis also tells us that there
must have been a tremendous evolutionary pressure for intelligence in the very
late Pliocene. I get the sense that the go-to explanation for this, as with
later ‘jumps’ in cranial capacity that we can identify in the archaeological
record, is basically “climate variability” (plus vigorous waving of hands) (and
there is interesting climatological evidence of climate fluctuations coinciding
with key changes in the archaeological record, I am told). It is possible, however, that this explanation
is only a small part of the story. In general, we should worry about
evolutionary explanations that are too neat, that just make so much sense, because often the reason
they seem so intuitive to us seems to be that we are thinking completely the
wrong way about the issue. In general, evolution is something that’s very
difficult to reason about properly, and very easy to reason about very badly.
In this case, I think the story sounds, on the face of it, very plausible
because we think, “Oh, yeah, obviously if the climate was changing all the
time, intelligence would be a major boost in helping early hominins stay alive
because intelligence would allow you to remember how to find food in this
situation or that – i.e. would allow for flexibility and adaptability.” But
this kind of reasoning is not actually adequate: it’s a shallow,
non-evolutionary perspective on what would be useful within a single life; you
haven’t really explained the existence of persistent, long-term selection
pressures. The real way to investigate these things is not through idle
speculation, but through dumping one’s intuitions and employing
computer-modelling and the like. Luckily, I think there are some people out
there doing this. The point is just that we should be sceptical about master
explanations; the evolution of human intelligence was surely not simple and
unifactorial.
Anyway, enough epistemological
ranting… Back to the rollicking narrative.
Finally we have
arrived at Homo erectus, our most
exciting species yet, and probably the first hominin to leave Africa (certainly
the first to colonise the world, getting as far as Indonesia!). Homo erectus evolved around 1.9 million years ago, living through most of the
Pleistocene (latest fossil evidence being 143,000 years old, apparently). In
other words, it is a species which persisted on the planet far longer than
modern humans have been around. Of course, there is an interminable debate
between ‘splitters’ and ‘lumpers’ on the question of which fossils we should
classify where, with a particular controversy on the question of whether Homo ergaster should be seen as a
separate species. As Wikipedia notes, with some handy references, “Debate also
continues about the classification, ancestry, and progeny of Homo
erectus, especially in relation to Homo
ergaster, with two major positions: 1) H. erectus is
the same species as H. ergaster, and thereby H. erectus is
a direct ancestor of the later hominins including Homo heidelbergensis, Homo neanderthalensis, and Homo
sapiens; or, 2) it is in fact an Asian species
distinct from African H. ergaster.” Certainly, we can say, with
confidence and without controversy, that Homo
erectus was a very ‘successful’ species, insofar as it persisted for a long
period of time with key features staying the same. We’ll discuss these feature
in a short while; for the moment, we’ll quote Wikipedia on how the first fossils
of this species were discovered:
“The Dutch anatomist Eugène
Dubois was fascinated by Darwin's
theory of evolution especially as it applied to humankind. In 1886, he set out
for Asia—which
then was the region accepted as the cradle of human evolution despite Darwin's
theory of African origin; see Haeckel
§ Research—to find a human ancestor. In 1891, his team discovered a
human fossil on the island of Java, Dutch
East Indies (now Indonesia). Excavated from the bank of the Solo River at Trinil, in East Java,
he named the species Pithecanthropus erectus—from the Greek πίθηκος,[17] "ape",
and ἄνθρωπος,[18] "man"—based
on a skullcap (calotte) and a femur like that of Homo sapiens.
Dubois' 1891 find was the first fossil of
a Homo-species (or any hominin species) found as result of a
directed expedition and search—and which was inspired by Darwin's radical
theory that humans, like all other species, evolved from ancestral species,
see human evolution. (The first found and recognized
human fossil was the accidental discovery of Homo neanderthalensis in 1856,
see List of human evolution fossils.)
The Java fossil from Indonesia aroused much public interest. It was dubbed
by the popular press as Java Man; but few scientists accepted Dubois' argument
that his fossil was the transitional form—the so-called "missing link"—between apes and
humans.[19] Java
Man is now classified as Homo erectus.
Most of the spectacular discoveries of H.
erectus next took place at the Zhoukoudian
Project, now known as the Peking Man Site,
in Zhoukoudian, China.
This site was first discovered by Johan Gunnar Andersson in 1921[20] and
was first excavated in 1921, and produced two human teeth.[21] Canadian
anatomist Davidson Black's initial description (1921) of a
lower molar as belonging to a previously unknown species (which he named Sinanthropus pekinensis)[22] prompted
widely publicized interest. Extensive excavations followed, which altogether
uncovered 200 human fossils from more than 40 individuals including five nearly
complete skullcaps.[23] German
anatomist Franz Weidenreich provided much of the
detailed description of this material in several monographs published in the
journal Palaeontologica Sinica (Series D).”
One thing that we should note about the
features of Homo erectus is that…
they do vary quite a bit. Taking a very broad perspective, I think it would be
fair to say that the ‘lumpers’ won out in the case of Homo erectus. Some Homo
erectus fossils have been found which are indicative of male height
reaching six foot (Turkana boy may have grown to reach 6’1”, I am told),
whereas others show a height comparable to that of modern pygmies, and cranial
capacity varies in a similarly dramatic way (though, to be fair, we obviously
do see significant height differences between ethnic groups in Homo sapiens so the case that the
‘lumpers’ won out is not totally straightforward). The creepy thing about the
early Homo erectus fossils is that
they seem to combine a cranial capacity not massively bigger than that of Homo habilis specimens (850 cm3)
with significant height. To me, this is really the stuff of nightmares. Imagine
confronting a strong, highly athletic brute with such severe microcephaly… Run!
The Javan specimens apparently measure up to 1100
cm3 cranial capacity, which overlaps with modern humans (they would
probably appear to us to have pretty small heads, but maybe not freakishly so
(the lack of forehead/shape of the skull would have been freakier than the
size)).
Homo
erectus was possibly the first species to have
lost specific adaptations for swinging from trees, with more human-like arms
and hands (http://www.sci-news.com/othersciences/anthropology/science-homo-erectus-human-like-hand-bone-01620.html),
and probably a very human-like gait and posture. This article just linked also
contains some detail on what we know about the Homo erectus diet from a combination of just looking at its teeth
and jaw, and looking at the ratio of different carbon isotopes in fossil bones
(this ratio changes is dependent on long-term dietary habits (we care about
Carbon 4 in particular)). It seems Homo
erectus specimens were about as omnivorous as us.
Actually, the diet of Homo erectus leads us naturally to the really interesting shit
about Homo erectus. THEY USED STONE
TOOLS AND THEY USED FIRE. They pioneered the cooking of meat, which Richard
Wrangham (a man who will crop up later, when we finally discuss the saucy
issues of hunter-gatherer violence and warfare) reckons may have been a crucial
factor in the evolution of human physiology and intelligence (https://en.wikipedia.org/wiki/Catching_Fire:_How_Cooking_Made_Us_Human).
There seem to be reasons to doubt this hypothesis – or at least doubt the
extent of its explanatory power (especially since our ancestral line was
experiencing rapid increase in brain size before cooking was developed). But the
idea is certainly not completely stupid either.
It is thought that Homo erectus may have also pioneered the ‘hunter-gatherer’
lifestyle. Most of the specimens found seem to show a stronger degree of sexual
dimorphism than we can see in Homo
sapiens, which may suggest that certain aspects of their sociality were not
exactly like ours (though it certainly doesn’t impugn the idea that they led a
‘hunter-gatherer’ lifestyle). Reduced sexual dimorphism likely goes hand in
hand with reduced male competition for ‘mates’, so it may be that young Homo erectus males fought each other
more than we do (their behaviour may have been more chimp-like than ours).
This, however, is pretty rank speculation. And arguably another reason to be
slightly wary of such claims is that we’re talking about a species that seems
to have developed culture, at least in primitive form (https://www.nature.com/news/homo-erectus-made-world-s-oldest-doodle-500-000-years-ago-1.16477)!
As for the question of how and at what level
of complexity Homo erectus communicated,
the jury is out on that question. I don’t think anybody really knows, and the
question of how the human language faculty evolved is a very vexed and heated
one in general (http://itre.cis.upenn.edu/~myl/languagelog/archives/002422.html).
That link I just gave you leads to several other papers that are worth reading
if you want to find out more about what (generativist) linguists think of these
issues. I get the impression from the online Twitter and blog statements of the
eminent palaeoanthropologist John Hawkes that the Chomskyan ‘spandrelist’
hypothesis (the most recent statement and defence of this hypothesis can
be found in the 2015 book Why Only Us? by
Berwick and Chomsky, which is unfortunately already way out of date on human
origins, but which certainly contains some interesting arguments, if very
little linguistic evidence) is not taken all that seriously by people within
his field, who instead think that a story more akin to Jackendoff or Pinker’s
must be true: that is, they seem to think that the human faculty of language is
not a beautiful snowflake-like structure which originated suddenly as a
mutation, probably only in Homo sapiens, that
aided thought by enabling recursion and was only secondarily ‘externalised’,
but that the human faculty of language is a very messy thing that was shaped by
selection pressures for greater communication, co-evolving with other aspects
of hominin anatomy (like the development of the larynx and skull, etc). The
Chomskyan hypothesis does seem prima
facie perhaps a bit mystical… but there are really thought-provoking
arguments in favour, too. Two of the most compelling are these: a) recursion is
an all-or-nothing property that would (so the story goes) have to come about in
one go and allegedly is not discernible in birdsong or in the communication
systems of any other species; b) human language is seemingly almost perfectly
modality-independent (sign language is just as syntactically complex and
natural to learn as language expressed through the vocal tract), which seems to
suggest that it did not co-evolve with communication systems and instead that
the faculty of language (as a faculty of thought) connects to sensory-motor
systems by an interface. (For more, you should read this book Why Only Us? [2015]). Anyway, Jackendoff
and Pinker have very powerful arguments of their own. In fact, the fundamental
understanding of how the language faculty works out in the human-mind that
Jackendoff explicates in his truly superlative book Foundations of Language (http://npu.edu.ua/!e-book/book/djvu/A/iif_kgpm_Foundations%20of%20Language.pdf),
with loads of interaction between semantics and syntax and morphology and
phonology, is fundamentally incompatible with the Chomskyan/Berwickian/Fitchian
hypothesis. So, for his part, he can’t really disagree without throwing out some
of his fundamental claims about the mind, which do seem to have more empirical
support behind them in linguistic evidence than Chomsky’s ‘minimalist’ position
(that he has held since the 90s). On the other hand, I do agree with Chomsky
that Jackendoff and Pinker, and other people writing about the evolution of the
language faculty, often fall into the trap of reasoning very badly about the
issues and making up convenient stories. As Chomsky wittily notes, people
sometimes forget that we want to know how the language faculty evolved (how the human means for language acquisition
evolved (how the L.A.D. evolved)), not how language
evolved – and too often the stories, though claiming to be explaining the
former, present narratives almost entirely divorced from computational details
and relying almost totally on plausible-sounding hand-waving about the
increasing ‘social tendencies’ of hominins in the Pleistocene and such like.
These issues are not easy, in short.
To return to the immediate issue of to what
extent Homo erectus ‘humans’ could
talk, the answer is (as I already said) that we don’t really know. However, I
do think pretty much everyone reckons that Homo
erectus probably didn’t have our linguistic
capacities; I think that pretty much everyone reckons that if you threw a Homo erectus child into a modern
environment, looked after by responsible foster parents and educated in the
modern education system, they would be mute and dumb (or at least close to).
One might think that genetic evidence should be able to sort this out for us. However,
this is a bit naïve, since the genetic correlates of language, like the genetic
correlates of everything, are super non-simple (Why Only Us? has its own take on what the genetic research on language
(the studies of FOX-P2 and its variants) does and does not show which I also
found interesting, when I read it). Nevertheless, one idea that gets tossed around
quite a lot which certainly impugns the
idea that Homo erectus had complex
language is the thesis that the origin of primitive art and symbolic rituals is
connected to the origin of complex (recursive (?)) language, and we haven’t
found much or any (?) evidence of complex burial rituals associated with Homo erectus remains… I am sure we will
learn more over the coming decades.
I forgot to note that Homo erectus is also characterised by a far greater orthognathism
than its ancestors and cousins. You can see that artists’ representations of Homo erectus ‘people’ are very much in
the “uncanny valley” in terms of their facial morphology. I think that if they
were still around today, many fewer people would doubt Darwin! Where’s the missing link? Over there, with the humanly proportioned
arms and legs, and human-ish mid- and lower-face, hooting but also nursing its
young and making tools!
That’s HOMO ERECTUS BABY!
A few years ago, I think it may have been
consensus within palaeoanthropology that there was this species related to (but
slightly smarter than) Homo erectus that
is the more direct common ancestor of both Neanderthals and Homo sapiens called Homo heidelbergensis. I get the impression from watching some
recent conferences and reading some stuff that people are less keen on this
species nowadays, and that some reckon we should just talk about erectus as the common ancestor of Neanderthals
and denisovans and sapiens (and this species, which may not
descend from heidelbergensis, may be
our direct ancestor: https://en.wikipedia.org/wiki/Homo_rhodesiensis). But this species still has its own
Wikipedia page as if it is not just a subspecies of erectus (https://en.wikipedia.org/wiki/Homo_heidelbergensis).
Basically, what this name Homo
heidelbergensis seems to range over is all those fossils that date from between
700,000 and 60,000 years ago that have brain cases larger than 1100cm3
and a facial morphology closer to that of modern humans than that of Homo erectus. One cool thing about this
species is that some specimens seem to be super fucking tall… “According
to Lee R. Berger of the University of the Witwatersrand, numerous
fossil bones indicate some populations of H. heidelbergensis were
"giants" routinely over 2.13 m (7 ft) tall and inhabited
South Africa between 500,000 and 300,000 years ago.”
As for the other
spicy stuff you’re desperate to know about this species, let me quote Wikipedia
once more:
“Social behavior[edit]
Recent findings[33] in
a pit in Atapuerca (Spain) of 28 human
skeletons suggest that H. heidelbergensis might have been the
first species of the Homo genus to bury its dead.[34]
Steven
Mithen[35] believes
that H. heidelbergensis, like its descendant H.
neanderthalensis, acquired a pre-linguistic system
of communication. No forms of art have been uncovered, although red ochre,
a mineral that can be used to mix a red pigment which is useful as a paint, has
been found at Terra Amata excavations in
the south of France.
Language[edit]
The morphology of the outer and middle ear
suggests they had an auditory sensitivity similar to modern humans and very
different from chimpanzees. They were probably able to differentiate
between many different sounds.[36] Dental
wear analysis suggests they were as likely to be right-handed as modern people.[37]
H. heidelbergensis was a close relative (probably a descendant) of Homo
ergaster. H. ergaster is thought to be the first
hominin to vocalize using a mix of vowels and consonants to communicate with
other members of its species,[35] and
that as H. heidelbergensis developed, more sophisticated
culture proceeded from this point.[38]
Evidence of hunting[edit]
A 300,000-year-old archeological site in
Schöningen, Germany contained eight exceptionally well-preserved spears for hunting, and various other wooden
tools. 500,000-year-old hafted stone points used for hunting are reported
from Kathu Pan 1 in South Africa, tested
by way of use-wear replication.[39] This
find could mean that modern humans and Neanderthals inherited
the stone-tipped spear, rather than developing the technology independently.[39][40]”
With Homo
heidelbergensis, we’re finally talking about a creature that, if it hopped
on your bus, you perhaps wouldn’t immediately recoil in horror or dismay. As
that short ‘Language’ section suggests, a Homo
heidelbergensis kid would probably not be quite as cognitively disabled in
human society as a Homo erectus kid
(for the moment, we’ve gone along with the idea that these are two taxonomic
groups worth distinguishing), although the average Homo heidelbergensis kid may still be diagnosed as severely
retarded, hard to say.
Homo heidelbergensis
evolved into Homo neanderthalensis. And the Wiki article on the Neanderthals is
so fucking good that there is no point extracting passages or summarising. Here
it is: https://en.wikipedia.org/wiki/Neanderthal.
And here’s the article on the Denisovans, who interbred with Melanesian peoples:
https://en.wikipedia.org/wiki/Denisovan.
Once you’ve read these, you’ll be pretty much done, in terms of knowing
everything “you need to know”.
I will finish by briefly reviewing one of my
favourite topics: to what extent life was “nasty, poore, brutish and short” for
our hunter-gatherer ancestors. In my discussion of The Better Angels of our Nature way back in 2015 (http://writingsoftclaitken.blogspot.com.au/2015/12/an-extremely-long-essay-called-are.html),
I wrote the following on Pinker’s statistics on warfare-related deaths in
hunter-gatherer and hunter-horticultural societies:
“It seems that most anthropologists disagree
with Pinker on the figures of non-state peoples found to have died in war. One
is the respected Rutgers University anthropologist Brian Ferguson, who has a
very strong reply to Pinker’s early stats on hunter-gatherer and
hunter-horticultural violence, analysing very carefully the origin of the
statistics and how they are often pressganged (rather unscientifically) to
bolster a particular evo psych agenda. Naturally, the people who do this claim
they are the ones fighting against a political agenda, namely, a
“neo-Rousseauian” agenda/political correctness (yes, everything is ideology).
Ferguson’s monograph can be found here: http://www.ncas.rutgers.edu/sites/fasn/files/Pinker's%20List%20-%20Exaggerating%20Prehistoric%20War%20Mortality%20(2013).pdf
As Ferguson reveals, there is no doubt that
Pinker is very committed to a view of evolutionary psychology inherited from
figures like Edward O. Wilson, Martin Daly, Margaret Wilson, John Tooby and
Leda Cosmides, and consistently draws on this in all his books (Pinker does
tend always to cite the same people). Presumably, Pinker would justify this by
saying that the evidence supports the kind of evo psych propounded by these
thinkers, and it is of course true that there is plenty of evidence in today’s
world for the darkness of man and so on. As I’ve already made clear, my own
personal disposition on human nature (particularly male nature) is definitely
Hobbesian and misanthropic, so I understand this. But I also think that
Ferguson is very much justified in questioning the data. The data isn’t nearly
so iron-clad as Pinker would like to think – not even close. Ferguson’s
conclusion beautifully illustrates how wrong he thinks Pinker is: “Is this
sample [Pinker’s list] representative of war death rates among prehistoric
populations? Hardly. It is a selective compilation of highly unusual cases,
grossly distorting war’s antiquity and lethality. The elaborate castle of
evolutionary and other theorizing that rises on this sample is built upon sand.
Is there an alternative way of assessing the presence of war in prehistory, and
of evaluating whether making war is the expectable expression of evolved
tendencies to kill? Yes. Is there archaeological evidence indicating war was absent
in entire prehistoric regions and for millennia? Yes. The alternative and
representative way to assess prehistoric war mortality is demonstrated in
chapter 11, which surveys all Europe and the Near East, considering whole archaeological
records, not selected violent cases. When that is done, with careful attention
to types and vagaries of evidence, an entirely different story unfolds. War
does not go forever backwards in time. It had a beginning. We are not
hard-wired for war. We learn it.” Does Ferguson go too far the other way?
Perhaps. But Pinker is undoubtedly on thin ice in this area.”
I still pretty much stand by this, even if I
am also more confident now that Ferguson definitely goes too far the other way
(his rhetoric is way too strong!). Also, apparently the evidence from European
genomes is strongly against the hypothesis that agriculture spread through
Europe by means of cultural transmission, and instead testifies to a rapid
takeover of Europe by the agriculturalists from the Levant between in a few
thousand years before 5000 B.C. (https://www.ncbi.nlm.nih.gov/pubmed/2030731),
which strongly suggests that there was warfare ‘before civilisation’ in which hunter-gatherers
clashed with hunter-horticulturalists or full-time farmers, whether or not we
can find evidence of this in archaeology.
One thing that does really fascinate me is
that it has seemingly become orthodoxy among palaeoanthropologists, anthropologists
and prehistoric historians these days that, even if there was a quite considerable
degree of inter- and intra-tribal violence (homicide) among hunter-gatherers,
the advent and takeover of agriculture actually dramatically reduced the
quality of human life for, well, literally thousands of years, with massively
increased disease due to the greater population density and close proximity to
animals, a less healthy and less diverse diet, greater social inequality,
greater gender inequality, and (without doubt) greater social conflict and
violence due to the fact that people were crammed together with conspecifics
who weren’t kin. It seems that quite a few archaeologists, anthropologists and
other experts claim that only in the 20th Century did we return to the
average hunter-gatherer life expectancy (see, for example, the discussions in Peter
Turchin’s Ultrasociety or Yuval Noah
Harari’s Sapiens[5]).
Also, a very recently published analysis on
the long-term historical data on human violence suggests that it is a kind of
brute fact about human societies that there is a proportionally higher level of
violence in small groups than large groups, and that this is independent of
institutions: http://www.sciencemag.org/news/2017/12/why-human-society-isn-t-more-or-less-violent-past.
There is certainly plenty to doubt in the Pinker worldview…
13 pages seems enough. I’ll stop now.
[1]
Ok, well obviously the irony here is that I am using this as my launching pad,
even as I’m shooting it down as a sensible launching pad. I know this is dumb
and I’m not proud.
[2]
One thing that’s important to bear in mind is that the species we have to plot
the timeline of human evolution (especially this far back) are an essentially
miscellaneous subset of the total species that were around. There are plenty of
species that we will never recover.
[3]
Incidentally, important to be clear on this word “hominin” and its relation to
the word “hominid”: https://www.thoughtco.com/what-is-a-hominin-reassessment-171252
[4]
These kinds of locutions seem indispensable but you should always maintain
awareness that when people say stuff like “The first species of the Homo
genus,” that is less a crystalline fact about the world, and more a kind of
internal taxonomic tautology: we have declared that these fossils are the first
hominins, certainly using rational criteria but not in a way that avoids
arbitrariness altogether.
[5] This
latter book had essentially nothing to teach me and was pretty intellectually
insipid (covers an absurd amount, in pathetic detail), and I wouldn’t recommend
it to smart people (the sequel, about ‘our future’, sounds pretty laughable (it’s
easy to come up with random futuristic-sounding shit like future humans/cyborgs
will “worship data”, and it is not intellectually serious)).
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