Technological evolution stimulates – and
is stimulated by – the evolution of bigger brains and
bodies
Thomas Edison couldn’t have produced his light bulb
if a host of previous inventors hadn’t made discoveries
ranging from the manufacture of glass to the production of
electricity. Edison didn’t even come up with the basic
idea of passing an electric current through a resistant filament
inside an oxygen-free glass container: a patent based on that
concept had already been granted to Matthew Evans and Henry
Woodward in 1875, and several other people had, by that time,
produced light bulbs of one kind or another. Edison’s
contribution to the production of a commercially viable light
bulb took the form of buying Evans and Woodward’s patent,
and “tweaking” it – mainly by looking for
a filament that would burn longer than those currently in
use. When he started that search in 1878, a light-bulb developed
by Sir Joseph Wilson Swan, an English physicist, had just
set a record of 13.5 hours. By examining literally thousands
of plant species, Edison found a cotton-derived fiber which
delivered 40 hours of light in 1879, and then, in 1880, a
Japanese bamboo-fiber which extended that time to 1,200 hours.
The bamboo fiber was replaced by a tungsten filament a few
years later, but by that time, Edison’s “invention
of the light bulb” had, in the general opinion, already
become a fait accompli.
We must not conclude from this account that Edison’s
work on light bulbs was overrated. All inventors rely more
or less heavily on the work of their fellow-inventors, and
Edison’s investigation of the things that happen inside
light-bulbs was to leave a particularly large number of inventors
indebted to him: he had learned, in the course of making that
investigation, that electricity could flow across the vacuum
inside those bulbs, from the hot filament to a metal wire.
The discovery of this “thermionic emission” or
“Edison effect” led directly to the invention – by
one of Edison’s engineers – of the vacuum tube.
That device was to be of crucial importance in the development
of radio, television and computers, and would eventually stimulate
a search for the semiconductors which would perform its functions
in more powerful and versatile ways.
It’s in the nature of technological advance to breed
fresh technological advances. Each invention tends, therefore,
to increase the invention-producing capacity of the community
in which it arose, in much the same way as the accrual of
compound interest increases the capital which earned it.
Our family’s entry into the “cognitive niche”
we spoke about in Chapter 11 did not, therefore, simply lift
hominids up onto a new plateau of ecological and economic
power and then leave them there. It started, instead, to propel
their technological development along a growth-curve which
rose slowly for a long time, before climbing abruptly into
the ever-steepening ascent which it’s presently making – a
curve which is (as my comparison with compound interest has
already suggested) following a more or less exponential trajectory.
* * *
I suggested, in Chapters 9 and 10, that an enhanced ability
to make tools and weapons may, by 2.5 million years ago, have
allowed at least one of the australopithecine species to hunt
medium-sized herbivores, and to stand its ground against some
of the carnivores that would have been competing with it in
that activity. For a hominid population developing these kinds
of abilities, group action with wooden spears and thrown rocks
might have replaced tree-climbing as the prime defensive strategy
against its competitors and predators. That kind of shift
in strategy would presumably have relaxed – and perhaps
reversed – the selective pressure which had, (as I argued
in Chapter 9) up to that time, been restricting that and other
hominid species to a size which would permit fast and agile
tree-climbing.
For this and/or other reasons Homo erectus had,
by 1.7 or 1.6 million years ago, become, in Richard Leakey’s
words, “tall, athletic and powerfully muscled.”
“Even the strongest modern professional wrestler,”
Leakey tells us, “would have been a poor match for the
average Homo erectus.” A million years later,
the bodies of H. heidelbergensis, a European descendant
of erectus, were still exceptionally big and strong.
The Schöningen javelins we’ll talk about presently
are heavy enough to suggest that they were, as Robin Dennel
put it, “best used by large, powerfully built people.
The extremely robust Boxgrove tibia appears to have belonged
to such a person.”
The female members of erectus-to-be underwent an
even bigger growth-spurt than the males, diminishing the big
size-difference between the sexes that characterized the australopithecines.
* * *
The dramatic and relatively abrupt increase in the body-size
of the species that was becoming Homo erectus, was
accompanied by an equally radical change in the shape of this
new hominid’s body. Its forearms became shorter, while
its legs, and more especially its thighs, grew longer. Its
narrow shoulders gave way to broad ones, while its waist grew
long and relatively slender. Beginning with an article by
Denis Bramble and David Carrier in a 1983 issue of Science,
entitled “Running and Breathing in Mammals,” a
number of theorists have argued that these changes in body-shape
came about in response to the demands of running.
How, one might ask, could running have played a part in our
evolution if it didn’t offer our species some kind of
advantage over other animals? Don’t humans run much
more slowly than most other animals? The answer is
that, slow as they are, humans are able to outrun a great
many other species over long distances. We’re
able to do this because we’ve evolved highly effective
ways of dissipating the heat generated by sustained physical
activity. Natural selection has elaborated and multiplied
our “eccrine” sweat glands (as opposed to the
“epicrene” kind which is associated with hair
follicles and scent production) to the point where it’s
quite inappropriate to speak of “sweating like a pig”:
humans perspire far more heavily than pigs, and, indeed, most
other mammals.
The cooling caused by the evaporation of our sweat is enhanced
by the fact that our skins are largely hairless. The selective
pressure that stripped us of our body-hair must have been
powerful, because there would have been significant countervailing
demands for the retention of that covering. Much of the territory
in which hominids evolved is high country in which sub-zero
temperatures are common. Just as hairlessness could, and probably
did in some cases, cause hominids to freeze to death on winter
nights on Ethiopia’s mountains and South Africa’s
highveld where snowfalls are not uncommon, it would have exposed
them to sunburn on hot days, and contributed, under such conditions,
to the dehydration and demineralization risks posed by the
prodigious power of their eccrine sweat-glands.
When did hairlessness emerge? Newborn human infants still
exhibit a reflex which produces a grip strong enough to bear
their own weight. This “gripping reflex” must
have evolved to grasp the mother’s body-hair. The fact
that it still exists suggests that hairlessness must have
evolved relatively recently. It seems reasonable to assume,
therefore, that it might have come into being in concert with
the other cooling mechanisms which contribute to the extraordinary
long-distance running capabilities which Homo erectus
seems to have possessed by some 1.7 million years ago.
Because of a variety of specialized adaptations, such as
kidneys which minimize water loss, some desert antelopes can
go without drinking water indefinitely. Oryxes, dik-diks and
others with adaptations of this kind, let their body temperatures
rise to levels that would be lethal to their brain tissue
rather than loose moisture by using water to cool their core
temperatures by sweating. They’re able to do this by
selectively cooling, through the evaporation of mucus inside
their nasal cavities, of the blood that flows to their brains.
The cooling system which Homo erectus evolved is,
by contrast, designed to cool its entire body – its core
temperature. Could the evolution of a cooling system which
makes such prodigal use of water have been facilitated, one
wonders, by the fact that the hominids in question had had
learned to transport and/or cache water in calabash shells,
the shells of ostrich eggs, or other “ready-made”
containers of that kind?
Having “opted” for full-body cooling, our genus
does not have the elaborate vascular networks which many dry-country
antelopes have evolved for the selective cooling of their
brains. It does, nevertheless, seem to be capable of some
degree of differential brain cooling. In a 2004 article in
Nature, Denis Bramble and Daniel Lieberman argue
that our venous circulation may be “designed”
to carry blood cooled by sweating on the scalp and face, back
into the interior of the skull to cool, by countercurrent
heat exchange, arterial blood on its way to the brain by way
of the internal carotid artery. Dean Falk and Michel Cubanac
report, too, that emissary foramina – tunnels which conduct
brain-cooling veins from the scalp through the skull to the
dura mater or outer cover of the brain – were significantly
increased in the gracile australopithecines which split off
from their robust counterparts between 3 and 2.5 million years
ago.
* * *
The 2004 Nature article by Bramble and Lieberman
which I’ve just quoted, is the most comprehensive argument
to date that anatomy and the physiology of Homo erectus
were extensively adapted to long-distance or endurance running.
The demands created by walking are, Bramble and Lieberman
point out, very different from those created by running. Swing
your right leg forward while walking, and you will – Newton’s
third law of motion tells us – create an equal and opposite
reaction that will tend to turn the rest of your body on its
axis in a clockwise direction. That potentially destabilizing
reaction is counteracted by our hip muscles: via the left
foot, which is in contact with the ground, they exert a countervailing,
anticlockwise torque which – quite literally – keeps
us on track.
Running creates larger rotational forces than walking. Those
forces cannot, however, be counteracted though a connection
with the ground, because running bodies become airborne between
toe-off and heelstrike. Natural selection has, therefore,
elaborated a different way of counteracting that rotation:
as the pelvis rotates in a clockwise direction, to sweep the
left leg sweeps forward, the chest makes a sharp anticlockwise
rotation, to neutralize the reaction to the legs and pelvis.
“Sawing” arms attached to wide shoulders add momentum
to this countervailing torque.
The chest of a running hominid like Homo erectus
could not counter-rotate as effectively as it did, if its
connections to the rest of the body, i.e. to the head and
the lower body, were not highly flexible. This is the reason,
Bramble and Lieberman argue, why erectus evolved
a waist which was narrower, longer, and more flexible than
that of a chimpanzee or an australopithecine. We cannot, however,
set too much store by this “long and flexible waist”
argument: Dr Guillaume du Toit, a spinal surgeon who practices
in Cape Town, informs me that most of the torsion which allows
our species to rotate its upper body and shoulders so effectively,
takes place in a region of the thoracic spine near the level
of the shoulder blades.
The need to counter-rotate the chest and shoulders is also,
Bramble and Lieberman argue, the reason why erectus
developed the long, flexible neck which still characterizes
our genus. In chimpanzees, the head is connected to a pair
of narrow, “shrugged” shoulders by numerous powerful
muscles, advantageous for tree-climbing, and this, these authors
assert, was also the case with the australopithecines. In
Homo erectus and its descendants, those muscles are
reduced in size, or completely absent. The result is a head
which can maintain an “even keel” during running,
rather than being made to “yaw” – rotate back
and forth on its axis – by the rotation of the shoulders.
Bucking this trend toward reducing the muscular connections
between the head and the trunk, erectus-to-be evolved
a so-called “nucchal ligament” – a connection
between the back of the head and the spine which had the effect
of preventing its head from pitching forward and back in response
to the heel-strikes and toe-offs of running. Ligaments of
this kind are, Bramble and Lieberman tell us, present in species
which are either adapted to running, or massive. Australopithecine
skulls, they report, lack the “nucchal shelf”
to which they are attached.
* * *
Increasing the ability of the chest and shoulders to rotate
independently of the lower body and the head didn’t
only allow erectus-to-be to run more efficiently – it
also permitted it to become an excellent thrower.
Bramble and Lieberman argue that this “decoupling”
of the chest from the pelvis and the head, is what allows
our stance to remain firm, and our heads to retain a fixed
orientation to the target, while our chests and arms rotate
rapidly and forcefully with the throwing motion.
The Schöningen javelins which we’ll talk about
presently, provide direct evidence that Homo erectus-like
beings were using throwing-skills to hunt by nearly 400,000
years ago. We’ve seen, though, in Chapter 9, that one
or more hominid species was hunting medium-sized prey by 2.6
million years ago. It seems likely, therefore, – especially
in view of the fact that Homo erectus’ distinctive
body-shape is already fully developed in the partial skeleton
of the 1.6-year-old “Turkana boy” discovered by
Richard Leakey in 1984 – that a selective pressure in
favor of forceful, accurate throwing had already started to
operate in the late Pliocene.
I suspect, for these reasons, that when we see a baseball-
or cricket player execute a sizzling, flat-trajectory throw
from the outfield straight into the hands of a catcher or
a wicket-keeper to run someone out, we’re witnessing
a skill which was already in existence in the early Pleistocene.
If the big, powerful hominids of the early and middle Pleistocene
were able to throw rocks with that kind of velocity and accuracy,
then carnivores – even big carnivores like machairodont
cats and Pachycrocuta hyenas – would have risked
serious injury by remaining in throwing-range of a group of
them.
* * *
The ability to throw missiles hard and accurately would have
given its possessors obvious advantages in hunting and in
conflicts with other predators who were trying to seize them
and/or their prey. Exactly what advantage did endurance running
confer on the genus Homo?
In a 1984 Current Anthropology article entitled
“The energetic paradox of human running and hominid
evolution,” David Carrier argued the thinkable: that
Homo erectus’ ability to run in a “perseverant”
way had evolved in response to that species’ strategy
of pursuing swift, open-country prey. (A capacity for endurance
running could, after all, seldom if ever help a hominid to
escape from a predator.) Apparently unaware of Carrier’s
writings on this subject, Wilhelm Schüle reached the
same conclusion independently in the 1990 “Paleo-ecology
of hunting” article we discussed in Chapter 12. “Tropical
carnivores,” Schüle wrote,
attack with great speed and succeed
instantly or otherwise abandon their hunt. Most of them hunt
by night. They cannot tolerate chasing prey for any amount
of time in tropical heat. Man, the naked, sweating animal
can do just that. Any well-trained jogger can outdistance
his dog on a hot summer day. The dog’s weight/surface
index is more favorable than man’s, yet its cooling
system is far less efficient.
Endurance running obviously isn’t needed to pursue
the kind of prey which chimpanzees hunt: tree-dwelling monkeys,
young forest-antelopes and squirrels. It would be needed,
as we’ve just seen, to hunt animals like savanna antelopes
and members of the horse-zebra family. These are precisely
the kinds of animals whose carcasses were butchered 2.5 million
years ago by the late australopithecine hominids we discussed
in Chapters 9 and 10.
Given the logical fit between the evidence which suggests
that those 2.5-million-year-old antelopes and equids may have
been hunted by the hominids who butchered them, and Bramble
and Lieberman’s “our bodies were shaped by long-distance
running” thesis, it’s surprising to learn that
these two authors still adhere to the obsolescent orthodoxy
that hominids did not hunt until recently. How, given that
view, do they explain their contention that endurance running
was important enough to our late-Pliocene ancestors to exert
a profound influence on the evolution of our anatomy and physiology?
Our need for endurance running could, they suggest, have been
created by scavenging. “Wild dogs and hyenas,”
Bramble and Lieberman argue,
often rely upon remote olfactory
and visual cues such as circling vultures to identify scavenging
opportunities and then run long distances to secure them.
Early Homo may have needed to run long distances
to compete with other scavengers...
I have to say – with plenty of respect for an article
which is, in the main, well-reasoned – that this isn’t
a convincing suggestion. The distances over which kills can
be seen by humans, and, indeed, seen or smelled by their four-legged
competitors, aren’t nearly long enough to give endurance
runners like ourselves an advantage over other animals. Bramble
and Lieberman themselves admit that the “well-conditioned
human runners” who can “occasionally outrun horses,”
only manage to do so over “extremely long distances.”
Circling vultures aren’t visible to humans at “extremely,”
or even moderately long distances. Investigations by the Northern
Prairie Wildlife Research Center showed that a black-painted
model vulture with a seven-foot, ten-inch wingspan, was “barely
visible” to an observer on the ground when released
from an aircraft at 4,700 feet (i.e. about .9 of a mile) above
the ground, and invisible without binoculars at 5,800 feet
(about 1.1 miles). Most of Africa’s larger mammals would
be able to outrun our species with ease over a one- or two-mile
distance. The African wild dog, Lycaon pictus, a
hunter that specializes in running down medium-sized antelopes
(and has, incidentally, very seldom been seen to scavenge)
can, according to Richard Estes’ Safari Companion,
run 35 m.p.h. for at least two miles, while elite human middle-distance
runners can barely manage 15 m.p.h. over that distance. Though
they are probably somewhat slower than Lycaon, hyenas
would also outdistance humans easily over a two-mile distance.
I argued in Chapter 10 that erectus-to-be had probably
become an expert at both larcenous and aggressive scavenging
by the beginning of the Pleistocene, but it seems clear that
the ability of this species to maintain a slow running speed
over uniquely long distances, was evolving in response to
the other strategy it employed to gain access to animal protein,
namely hunting.
* * *
Perhaps because Bramble and Lieberman reject the idea that
the evolution of our long-distance running abilities was driven
by hunting, they’re unreceptive to the idea that recent
human groups might have employed endurance running as a hunting
strategy. After a perfunctory discussion of this issue, they
conclude that endurance running is “not common among
modern hunter-gatherers.” That statement may be correct
with regard to the hunter-agriculturalists who live in rain
forests – an environment which our species has only entered
in relatively recent times – but there’s clear evidence
that many if not most of the hunter-gatherer groups who were
living in open country during the nineteenth and twentieth
centuries, did use endurance running to secure their prey.
Bramble and Lieberman themselves quote Peter Nabokov’s
Indian Running: Native American History and Tradition
in a footnote, but they do not discuss Nabokov’s accounts
of numerous Native American tribes using endurance running
to secure a wide variety of swift-running prey ranging from
jackrabbits to deer.
There are many other accounts of North American Indians tiring
out their prey by perseverant running. A classic book by Wendell
Bennett and Robert Zingg, The Tarahumara: An Indian Tribe
of Northern Mexico, published in 1935, describes how
members of that group chased down deer until the animals were
exhausted, and then throttled them to death by hand. In his
Why We Run: A Natural History, Berndt Heinrich tells
us that the Paiutes and Navajos were reputed to do the same
with pronghorn antelopes.
Heinrich reports, too, that Australian Aborigines chased
down kangaroos by forcing them to reach lethal body-temperatures.
It has also been frequently and reliably documented, that,
until very recently, the San hunter-gatherers of Southern
Africa’s Kalahari region killed antelopes and other
herbivores by pursuing them at an aerobic pace for many hours.
San hunters could and did run down unwounded animals, but,
even in cases where their quarry had been hit by a poison
arrow, they often needed to run after it for long distances,
to prevent it from being eaten by a competing carnivore, or
recovering from the effects of the poison and making its escape.
* * *
The genetic evolution which was giving erectus-to-be
its formidable long-distance running abilities and its relatively
big brain was, in the early Pleistocene, still “tightly
coupled” (as E. O. Wilson put it in his Consilience)
with the cultural evolution which was producing its toolkit.
Genetic and cultural evolution weren’t only moving at
a more-or-less similar pace – they were, in addition,
probably linked to each other in a positive feedback loop:
the development of more sophisticated tools might have contributed
to the selection of brighter tool-users, who might then have
produced still more sophisticated tools and so on.
Today these two kind of evolution are, of course, no longer
walking hand in hand. Technological evolution is, on the contrary,
moving at such enormous speed that it has completely outpaced
the “traditional” or gene-based evolution which
made it possible in the first place. Nobody would suggest,
for instance, that the physical and mental capacities of the
human species have undergone any noticeable change since the
beginning of the nineteenth century, but the technological
progress that has, since that relatively recent time, taken
us (as a recent article in Fortune magazine put it)
“from steam engines to search engines,” has been
so phenomenal that it challenges our ability to comprehend
it fully. The minds and bodies of present-day humans probably
aren’t even significantly different from those of the
people who created the sophisticated images of Europe’s
big animals in Lascaux Cave some 17,000 years ago, but the
development which our species’ technology has undergone
since that time has, from the Lascaux artists’ point
of view, been completely unthinkable. Cultural evolution has
raced ahead of its gene-based counterpart in this way, because
the latter is limited, as we’ve seen, to piecing together
useful new structures or behaviors from randomly-occurring
genetic variations over many generations, while our family’s
ability to innovate ontologically – to invent – can
literally bring useful new behaviors into existence overnight.
But the faculty which produces ontological innovations
could not, of course, have arisen overnight. The neural machinery
which runs inventive intelligence was, on the contrary, assembled – by
gene-based evolution – over many thousands of generations.
Regardless, therefore, of how explosive the growth of our
family’s technological power was eventually to become,
its initial development would not have been fast. The archeological
record confirms that this was the case: the Oldowan tool-kit
produced by garhi and/or its contemporaries in the
late Pliocene was very simple in comparison with later human
artifacts. What little change it would undergo over the next
million years, would, moreover, manifest itself very slowly.
Slow change is not, however, the same as no change. “Over
the several hundred thousand years evident in Olduvai’s
stratigraphy,” Roy Larick and Russel Ciochon tell us,
“Oldowan assemblages undergo distinct refinement in
chipping techniques and some standardization in tool form.
By 1.7 to 1.6 mya, bifacial tools help to define the Developed
Oldowan Industry.”
In the region of 1.6 to 1.5 million years ago, those bifacial
tools developed into the assemblage of heavy-duty scrapers,
cleavers, picks and “hand-axes” characteristic
of the so-called “Acheulian” or “Mode 2”
industry. Acheulian tools were dramatically bigger than their
Oldowan counterparts, and more efficient: “I can work
much faster with a cleaver or a handaxe than I can with a
small flake,” Nick Toth reports. “I can make longer
sweeps with them, I can cut deeper into the meat, and my fingers
don’t get as tired.”
Usually about as big as an open human hand, the teardrop-shaped
“hand-axes” were used as knives and saws, rather
than axes. The “cleavers” with their wide, chisel-like
front ends were probably used, inter alia, for the separation
of the skin and muscle, while the Acheulian “picks”
could have been used for the same purposes as modern picks
are – to loosen up earth for digging purposes.
Although the Acheulian industry is named after Saint Acheul
in France where its products were first found, it only appears
in the European archeological record in the F layer of Notarchirico
in Southern Italy, a horizon established by thermoluminescence
dating to be about 640,000 years old. By 500,000 years ago,
it is, however, found throughout Europe, from Boxgrove in
England, to Korolevo in the Ukraine.
* * *
The surge of technological development which brought these
new stone tools to Africa between 1.6 and 1.5 million years
ago, may have included a more varied and effective range of
wooden implements. We concluded in Chapter 10 that wooden
implements like digging-tools and spears must already have
been used by the makers of Oldowan stone tools. We saw, too,
in that chapter, that Lawrence Keeley and Nicholas Toth found
wear-polishes confirming that some of the “developed”
or late Oldowan stone tools they examined, were used to cut
or saw wood.
Archeologists have tracked hominid woodworking into the early
Acheulian period. Manuel Dominguez-Rodrigo and his associates
reported in the 2001, volume 40 of the Journal of Human
Evolution, 289-299, that wear-patterns on the edges of
1.6 million-year-old hand axes from Peninj in Tanzania, and
phytoliths adhering to the tools in the vicinity of those
edges, reveal that those tools were, in fact, used as “knives”
and “saws” to cut a variety of substances including
wood. We know, therefore, that woodworking of some sort was
taking place in the early days of the Acheulian industry,
but have not, to date, found any of the wooden implements
that would have been produced at that time. That’s not
unexpected: unless wood happens, by some odd chance, to end
up in an anoxic environment such as a peat deposit, it decomposes
relatively quickly.
A few wooden implements have been found in association with
later Acheulian technology. Apart from wooden artifacts
produced near the end of the African Acheulian around 200,000
years ago at Kalambo Falls in Zambia, all these finds have
been made in Europe. There’s an irony in that state
of affairs. Africa was the “big city” of hominid
activity during the Acheulian period, while Europe was a distant
suburb which only received that technology long after it was
developed in Africa. Now that Europe has become a “big
city” of industry, activities like civil engineering,
mining, building and farming (not to mention archeology) are
carried on there much more intensively than they are in Africa.
This means that more Acheulian material gets unearthed in
formerly “backward” Europe than on the continent
on which that industry was developed.
The most spectacular collection of Acheulian-produced wooden
implements discovered to date, came to light in the 1990s
near the town of Schöningen in Lower Saxony, in what
Robin Dennell describes in the 385, 1997 Nature as
“one of the many enormous, unsightly, opencast brown-coal
mines that dot the German landscape.” Destructive as
this mine may have been of the present-day German landscape,
its excavation revealed a succession of long-buried Middle-Pleistocene
environments. One of the levels it uncovered, number 4 of
the Schöningen II channel, included a lake-shore. The
pollen, mollusk-shells and other organic fragments recovered
from this layer, represent life-forms that were alive between
380,000 and 400,000 years ago, during an episode of relative
warmth just after the fifth-last interglacial maximum, which
is known in Germany as the Holstein Interglacial. Examining
a cache established by human hunters near the shore of that
ancient lake, Hartmut Thieme and his associates found the
remains of a hearth in which those hunters had made fires,
together with hundreds of stone tools, and a great many flakes
produced in the process of retouching those tools. A large
number of butchered animal-remains, mainly those of horses,
were also unearthed there, together with a finely-worked 30-inch
length of spruce wood, almost an inch and a quarter in thickness,
and sharpened to points at both ends.
Remarkable as the latter find was, it was overshadowed by
the discovery of seven well-preserved wooden spears. These
spears, which range from six feet to eight feet four inches
in length, are between 1.2 and 2 inches in diameter at their
thickest points. Each was made from the whole trunk of a young,
approximately thirty-year-old, spruce tree. Those young trunks
had been debarked, and their Astansätze, – the
beginnings of their side-branches – painstakingly worked
down. The spears’ points were carved from the bottom
ends of the trunks, where the wood is at its densest. Apart
from making for hard points, this means that the heaviest,
thickest parts of the spears are, like those of modern javelins,
situated toward the front. Those heavy front ends were – also
like those of present-day javelins – tapered down gradually
into slender, sharp points, leaving the spears’ center
of gravity about a third of the way from the front.
There had been previous indications that the pre-sapiens
inhabitants of Europe used wooden spears to hunt big game.
In 1948 in Lehringen, Germany, a reasonably well-preserved
yew spear was found inside the remains of an elephant dating
from the last interglacial 125,000 years ago; in 1911 the
tip of what could have been a spear was found at Clacton-on-sea
in England in deposits laid down at more or less the same
time as those in which the Schöningen spears were found;
and a round hole in a rhinoceros scapula found at Boxgrove
in England, dated to the sixth interglacial before the most
recent one – i.e. about 500,000 years ago – provides
possible evidence of a spear wound.
The world of Anglo-American paleoanthropology is, as we saw
in Chapter 10, still dominated by the idea that humans only
started hunting big animals near the end of the Pleistocene,
around 40,000 years ago. “To fit this picture,”
Dennel explains,
the Clacton and Lehringen spears were downgraded
to digging sticks or, imaginatively, snow-probes for locating
buried carcasses.
But the Schöningen discoveries are
unambiguously spears: to regard them as snow-probes or digging-sticks
is like claiming that power drills are paperweights.
* * *
Even before the discovery of the Schöningen spears,
it had been widely accepted among German anthropologists that
the early European members of the genus Homo were
expert big-game hunters. Perhaps the body of archeological
evidence in support of that proposition that has been found
on the continent of Europe is simply too physically big to
deny. Fully 60% of the enormously abundant bone fragments
which hominids had processed and accumulated at Bilzingsleben
in Thuringia are, for instance, those of big animals like
the “forest” or “straight-tusked”
elephant Paleoloxodon, woodland rhinos, aurochs,
horses and bears. The remaining 40% are evenly divided between
middle-sized animals like red and roe deer, and smaller vertebrates
like beavers, fish and birds. The Bilzingsleben site was occupied
at a time or times lying between 410,000 and 380,000 years
ago.
Large, pre-Neanderthal accumulations of animal remains, with
megafauna also represented heavily, have been found in association
with hominid tools at several other places in Europe, including
Fontana Ranuccio and Isernia La Pineta in Italy. Remains of
large animals dated between 300,000 to 700,000 years before
the present have been found in association with stone tools
in many European localities, including Toralba and Ambrona
in Spain, Arago and Terra Amato in France, and Notarchirico
in Italy. An excavation made in the process of constructing
the undersea rail link between England and France, uncovered
a 400,000-year-old, partially-butchered skeleton of an elephant
surrounded by stone tools at Ebbsfleet in Kent. Butchered
elephant carcasses dating from between 300,000 and 500,000
years before the present have also been found just above the
B layer of Notarchirico, and at Aridos I and II in Spain.
Whether we refer to it in general terms as Homo erectus
“senso latu,” (“in the broad sense”)
or speak more specifically of it as H. heidelbergensis,
it’s clear that the hominid species living in Europe
half a million years ago, was an expert big-game hunter. It
was a hunter which seems, moreover, to have enjoyed ascendancy
over Europe’s other predators. Mark Roberts, a British
archeologist who shares the “Continental European”
view that Europe’s early hominid inhabitants were regular
and successful hunters of big game, directed the excavation
and analysis of the remains of three adult Stephanorhinus
or “woodland” rhinos, which were killed and butchered
by erectus at Boxgrove in southern England, about
500,000 years ago. Each of those kills would, Roberts tells
us, have been “a magnet for other predators.”
Yet each carcass was skillfully cut up.
Fillet steaks were sliced from the spine and the bones were
smashed to get out the marrow. Only hunters in complete
control of their patch could have done that.
Where they are present on the bones of these rhinos, the
tooth-marks of those “other predators” overlay
the marks of this butchery, showing that animals like lions,
hyenas and wolves only got access to those bones after the
humans discarded them.
* * *
A wealth of archeological material we’ve been discussing
makes it clear that European hominids were already capable
of killing big game some 700,000 before the present – i.e.
even before the Acheulian industry entered that continent.
We also know, from evidence found at Terra Amata in Southern
France, as well as at Bilzingsleben and Schöningen, that
the hominids living in those places were, by at least 400,000
years ago, already controlling and using fire.
Did these two ancient European skills – big-game hunting
and fire-use – arise in Europe, or were they – like
the Acheulian tool-making industry – brought to that continent
after being developed somewhere else, at some even more ancient
time? It would hardly be surprising if the latter turned out
to be the case: the “big city” of human technological
innovation lay, as we’ve seen, in the continent of Africa
at this time, where the Acheulian industry had been in existence
for almost a million years before it spread into Europe.
* * *
Let’s talk about big game hunting first. Are there
any indications that hominids were hunting animals as big
as elephants, rhinos and hippos in Africa before they were
doing so in Europe?
As we saw in Chapter 9, the oldest cut-marked bones found
to date, the 2.6 million year old specimens unearthed at Bouri,
show that the tongue was removed from a medium-sized antelope,
and that the haunch was cut off the carcass of a three-toed
horse. Bone fragments found at nearby Gona, in a 2.6 to 2.3
million-year old deposit, display cut-marks which suggest
to Manuel Domínguez-Rodrigo and his colleagues, that
that Gona butchers “eviscerated carcasses, and defleshed
fully muscled upper and intermediate limb bones of ungulates.”
It seems, therefore, that the butchers of both Bouri and Gona
had early access to intact or nearly-intact carcasses. Carcasses
in that condition are, as I argued in Chapter 10, much more
likely to have come into the possession of their butchers
through hunting and/or aggressive scavenging, than through
passive scavenging.
I also argued, in that chapter, that hunters could seldom
have retained control of the carcasses of larger prey animals
if they were powerless over the carnivores which surrounded
them. There’s nothing far-fetched about the idea of
erectus (or erectus-to-be) becoming able
to drive off or kill big cats with spears. Many Africans killed
lions with spears during the Twentieth Century, and Alexander
(“Sasha”) Siemel (1880-1970), a Latvian who emigrated
to Brazil during the First World War, became famous for killing
jaguars with a spear. In doing so he was, however, simply
emulating a feat of which native Brazilian hunters have been
capable for millennia.
Evidence that early-Pleistocene hominids were exploiting
the carcasses of Africa’s biggest animals, is provided
by a number of “slaughter-sites” discovered in
East Africa, at which the whole or nearly-whole carcasses
of megaherbivores were dominated by hominids for periods of
time long enough to carry out more-or-less extensive butchery.
At Koobi Fora in northern Kenya, parts of a hippopotamus
carcass, dated to 1.9 million years b.p., were found in association
with simple stone tools. The skeleton of a Deinotherium,
some of whose bones were butchered and disarticulated, was
discovered in Olduvai’s 1.8-million-year-old FLK North
Lower Bed II in Tanzania, in association with 39 stone implements.
Another proboscidean – a member of the genus Elephas,
associated with 172 stone tools – was found at FLK North,
Upper Bed I, level six. This site is dated at between 1.7
and 1.5 million years before the present. Olduvai deposits
of this age have also produced several tool-butchered carcasses
of the long-horned buffalo Pelorovis.
The thoroughly-butchered skeleton of another Elephas – dated
at between 1.6 and 1.3 million years before the present – was
found with 569 Oldowan implements at Barogali in Djibouti,
a small country sandwiched between Somalia and Ethiopia. The
cranial roof of this animal had been smashed away from its
calvarium, presumably to get to the brain.
Is this catalogue of early-Pleistocene slaughter-sites a
short or a long one? Because he was doing field-work in Zimbabwe
during a time in which thousands of elephants were being culled
in that country, the American archeologist Gary Haynes was
given the opportunity of observing at first hand the “taphonomy”
or after-death fate of the remains of these animals. He was
also present in areas of Zimbabwe where thousands of elephants
had been shot by ivory hunters during the second half of the
Nineteenth Century. His observations in these killing-zones
brought him to the conclusion that the carcasses of large
animals are only preserved in highly exceptional circumstances.
The passage of one-and-a-half million years or more since
the early Pleistocene, would have further decreased the already-unlikely
prospect of finding a preserved elephant carcass. When we
consider in addition that Africa is, archeologically speaking,
a comparatively unexplored continent by contrast with Europe
and North America, the fact that six or more butchered carcasses
of megaherbivores have been found in that continent’s
early-Pleistocene deposits, cannot be taken as an indication
that hominid butcheries of such animals must, at that time,
have been infrequent occurrences. It could, in fact, suggest
the contrary.
* * *
We’ve seen that erectus had, by 1.6 million
years ago, become larger and more powerful than present-day
humans; that it could probably outrun the swiftest antelopes
over very long distances; and that it could probably deliver
“distance weapons” like thrown rocks or spears
with accuracy and power. These changes help to explain how
erectus could have become an effective hunter by
that time – even a very effective hunter – but
they do not, by themselves, explain how that big new hominid
species could have become destructive enough to drive some
of its prey animals and competitors into extinction.
It’s only when we return to a consideration of our
family’s ability to innovate on an ontogenetic level,
and focus on the degree of power which that unique ability
had conferred on erectus by the early Pleistocene,
that it can begin to seem understandable – and perhaps
even inevitable – that this species brought about the
hemorrhage of extinctions which depleted Africa’s large-mammal
diversity around 1.4 million years ago.
We’ve talked about the more effective and diverse kit
of stone tools which erectus started using in Africa
between 1.7 and 1.5 million years ago, and speculated that
the surge of technological development which ushered in those
tools probably included devices made of perishable materials
like wood and leather. The unprecedented degree of power which
its growing ability to innovate ontologically had conferred
on erectus by the early Pleistocene was most compellingly
manifested, however, by the fact it learned, during that period,
to control fire.
CHAPTER 14
– Fire
