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2000). Where available, and with the development of appropriate sea-going
technology, marine mammals became viable alternatives to terrestrial mam-
malian herbivores.
All this indicates pressures towards retention of hunter“gatherer lifestyles
whenever these were sustainable. However, once populations went down the
Survival of the weakest 203

route of food production, the competitive advantages conferred on farmers (in
spite of the many disadvantages, e.g. worsened nutritional condition and greater
propensity to disease) made the transition from hunting and gathering to food
production autocatalytic (Diamond, 2002). Among the advantages of a seden-
tary, food production, lifestyle is the reduction of the birth“birth interval with its
consequences for population growth (Diamond, 1997, 2002). Here we see the
outcome of a process of birth“birth interval reduction that would have started
with the social behaviour and mobility patterns of the early Moderns (Chap-
ter 5) that would have enabled a more rapid population growth and reduced
risk of extinction, all else being equal, than would have been the case with the
Neanderthals (Zubrow, 1989).
So what can we conclude were the essential characteristics required for the
origin of agriculture in the early Holocene? There were seven prerequisites:
(1) the availability of plants suitable for domestication (Diamond, 1997); (2)
wild resources permitting a hunting and gathering existence but with seasonal
de¬cits and an insuf¬cient range of alternatives to see populations through the
bad times; (3) a climate suitable for the growth of domesticated plants; (4)
heterogeneous landscapes that were characterised by high ecological diversity
and stepwise seasonal climatic shifts that would have favoured staggered growth
of crops (Diamond, 1997) and that would also have permitted an element of
hunting and gathering; (5) populations of humans with territorial exploitation
strategies that required the semi-permanent or sedentary existence of at least
part of the population; (6) populations of humans that had well developed
technology, systems of division of labour and storage; and (7) ecologically
stressed populations of humans.
Clearly, the climatic amelioration of the Holocene linked with the Modern
Human lifestyles that had evolved in the late Pleistocene increased the proba-
bility of some groups of humans discovering the bene¬ts of particular plants for
domestication. These would have originally grown naturally around camp sites.
Without an element of residence the establishment of the link between the sea-
sonal re-emergence of particular plants and the collection of their seeds would
be highly improbable. The pressure towards sedentism may have been demo-
graphic. Sedentism would have evolved to ensure access to the most productive
portions of a territory in the context of increasing competition (Rosenberg,
1998). Innovations would have arisen, as throughout human history, among
stressed populations living outside the tropics. Those in the temperate and bo-
real regions were unable to develop agriculture because of unsuitable plants
and climatic conditions. Those across the mid-latitude belt were prime candi-
dates. That agriculture arose independently on at least two occasions between
10.5 and 9.5 kyr, when it had not done so previously in the history of human
evolution, suggests that it could only have done so when all seven factors listed
204 Neanderthals and Modern Humans

above coincided. The later independent origins of agriculture in other parts of
the world also took place when all seven factors coincided.
Similar factors would have contributed to the herding, and subsequent domes-
tication, of mammalian herbivores. Herding would have evolved as an extended
form of storage, keeping the animals alive for use during the lean periods of
the year. The selection of those animals with docile characteristics would have
progressively generated strains that were easy to keep around settlements. This
is exactly what appears to have occurred in the case of goat domestication in the
Zagros Mountains in western Iran (Zeder & Hesse, 2000). Here the domestica-
tion process appears to have started around 10 kyr (and possibly even earlier)
through herd management. During the early phases managed goats may have
interbred freely with wild ones and selective breeding and control of sex ratios
and age structures was only gradually introduced afterwards.
I described in Chapter 2 how humans preferentially hunted intermediate size
mammals throughout their history. The preference for these intermediate size
classes continued to be exercised in the case of domesticated mammals. Suc-
cessfully domesticated large mammals, those that have been the most important
to humans, were almost exclusively Eurasian in origin (Diamond, 1997). Most
of the large mammals that were domesticated, including four of the ¬ve main
ones “ goat, sheep, pig and cow, had geographical distributions that included the
mid-latitude belt so it is not surprising to ¬nd early evidence of domestication
there, particularly in western Asia. Domestication was not limited, however, to
this belt. The ¬fth species, the horse, was essentially an animal of the steppes that
was herded and then domesticated in the plains of central Asia. Diamond (1997)
has suggested that the absence of native mammal domestication in Africa, the
Americas and Australia was related to the pool of locally available species that
could be domesticated. Although this may be true it may only be part of the
explanation. Hunting“gathering probably remained viable in most of these re-
gions, indeed continued until today in Australia, so that the pressure to move
towards animal (and indeed plant) domestication was not as great as in the mid-
latitude belt or the plains of Eurasia. Mid-latitude Eurasia continued to meet the
seven criteria outlined above for the origins of agriculture. The Eurasian Plains
satis¬ed these in respect of the horse. Horse domestication was in any case ini-
tiated, over 7 kyr, by people who also kept cattle and sheep (Anthony & Brown,
2000) so that the knowledge of herding and domestication was probably im-
ported and applied to a locally-abundant species. The domestication of the horse
may appear not to ful¬l criterion (4) below. The plains permitted a wide-ranging
strategy and movement between pastures at a scale that would not have been pos-
sible for species in the heterogeneous belt. The consequences would have been
similar to those for the smaller-scale seasonal movements of, for example, goats
and sheep “ animals could be moved to the best grazing areas at any particular
Survival of the weakest 205

point. The subsequent development of means of storing fodder for the lean sea-
sons was a cultural way of providing for these needs. Horse domestication was
also exceptional in that its main function was in increasing mobility, at least
from 5.5 kyr, even though it had started as a means of providing an additional
component in the diet (Levine, 1999; Anthony & Brown, 2000). We have seen
how, since the colonisation of the Eurasian Plains by Moderns, mobility across
their vast spaces that were largely free of topographic obstacles was the key
to survival. I view the domestication of the horse as a natural extension of this
adaptation, one that was to have signi¬cant consequences in the later historical
evolution of Eurasia (Fernandez-Armesto, 2000).
We can therefore re¬ne our seven criteria to incorporate animal domestica-
tion: (1) the availability of organisms suitable for domestication; (2) wild re-
sources permitting a hunting and gathering existence but with seasonal de¬cits
and an insuf¬cient range of alternatives to see populations through the bad
times; (3) a climate suitable for the growth or management of domesticated
organisms; (4) heterogeneous landscapes that were characterised by high eco-
logical diversity and stepwise seasonal climatic shifts that would have favoured
staggered growth of crops or seasonal movement of herding animals to new pas-
tures and that would also have permitted an element of hunting and gathering;
(5) populations of humans with territorial exploitation strategies that required
the semi-permanent or sedentary existence of at least part of the population; (6 )
populations of humans that had well developed technology, systems of division
of labour and storage; and (7) ecologically stressed populations of humans.


Two alternative ways of being human

We have seen how the unpredictable events of the Pleistocene were the driving
force behind human evolution. The colonisation of Europe and western Asia
by a Middle Eastern or, most probably, African population perhaps as far back
as half-a-million years ago led to a lineage of humans that evolved in relative
isolation. This lineage became identi¬able as the ˜classic™ Neanderthals around
120 kyr. The Neanderthals were intelligent humans, derived from the common
stock that also led to the Modern Human lineage. Their morphology was adapted
to those features that were most stable in the mid-latitude belt that stretched
from Portugal to the central Asian mountains “ the heterogeneous, species rich,
landscapes of the lower parts of the mountain ranges that dominated this vast
territory and the large mammalian herbivores that they consumed. Their in-
telligence permitted a degree of behavioural ¬‚exibility that enabled them to
survive through harsh as well as mild climatic conditions. The system per-
mitted their survival for tens of thousands of years. The constant Neanderthal
206 Neanderthals and Modern Humans

populations were distributed across the mid-latitude belt. Those that colonised
more temperate areas during mild climatic conditions became extinct each time
harsh conditions returned to Europe. The frequency of these harsh conditions
increased during the last glacial cycle and especially towards the end of OIS 3
around 50 kyr. Neanderthal populations became increasingly stressed. The last
populations, in a typically human response, attempted to adapt behaviourally
through technological innovation and changes in mobility but their morphol-
ogy, that had served them so well, could not change fast enough to permit
them to deal with the long range movements of the herbivores that increasingly
dominated a new world dominated by treeless vegetation. The last Neanderthal
populations became fragmented, isolated from each other and they disappeared
one after the other over a relatively short time period between 40 and 25 kyr.
The causes of the extinction of each population need not have been the same.
They may have included local competition from Modern Human groups, Allee
effects, disease, inbreeding, even random population ¬‚uctuations. An intelligent
and alternative way of being human became extinct.
A second intelligent type of human, closely related to the Neanderthals hav-
ing only diverged from them half-a-million years earlier, that had increasingly
invested in a gracile morphology that permitted them to reduce the risks of
the spatial and short-term temporal unpredictability of the African plains by
increasing their scale of operation, emerged from Africa around 100 kyr. These
Moderns had gradually developed increasingly complex and symbolic social
behaviours that improved the ¬‚ow of information between members of large
groups that exploited large home ranges. Large group sizes, home ranges and
complex social behaviour together enabled these Moderns to minimise risks
of living in unpredictable environments. The development of the neocortex in
these humans provided the necessary hardware for dealing with the complex
interactions within the group.
These early Moderns were apparently unable to penetrate immediately onto
the Eurasian Plain. It is very possible that the presence of the highly adapted
Neanderthals kept them in the periphery. They managed to spread eastwards,
perhaps via the Horn of Africa, keeping within tropical and sub-tropical climates
and probably reached Australia by at least 60 “ 55 kyr judging from the presence
of Moderns in Lake Mungo, deep in Australia, by 50 kyr. By 45 kyr, Neanderthal
populations were on the decline and this may have opened a window for the
Moderns to penetrate the Eurasian Plain. They may have done so simultaneously
along various points, into the Balkans from Asia Minor and onto the Russian
Plain from the Caucasus. I prefer the second alternative which has some support
from genetics and archaeology.
The complex behaviours of the Moderns became even more accentuated and
diversi¬ed on the plains of Eurasia. The rich mammalian herbivore resources
Survival of the weakest 207

scattered across vast open landscapes required complex ways of locating them,
accurate information transfer systems between individuals in the group, portable
and projectile technology, and social binding behaviours. Symbolism became
particularly important in a world in which individuals, for the ¬rst time, were
required to transmit and receive information relating to events that others had
not directly experienced.
These behaviours were not potentially unique to the Moderns. The Nean-
derthals could have evolved similar behaviours had they been exposed to the
social and ecological pressures demanded by this alternative way of dealing
with the world. I therefore maintain that Neanderthals were not cognitively in-
ferior to Moderns nor do I ¬nd support for a sudden mutation that generated the
complete package that made up the Modern Human overnight. Neanderthals
were simply different. A morphology and way of life that had become increas-
ingly complex and had been successful across the mid-latitude belt of western
and central Eurasia for close to half-a-million years disappeared because it was
not designed to cope with the speed and direction of change that hit Eurasia
at the end of the Pleistocene. The Moderns managed to survive the onslaught
of the LGM. With the subsequent global warming the world saw the rise of
a hominid that had the intelligence and an accumulated tradition of increas-
ingly complex technology, social behaviour that enabled re¬ned interactions
within large groups, systems of storage that reduced risk in times of shortage
and mobility strategies that together provided, in the right geographical cir-
cumstances, the necessary templates to deal with future stresses. These stresses
came from an expanding population and a reducing resource base. In the Mid-
dle East marginal groups that were ¬nding a hunting and gathering existence
increasingly dif¬cult learnt new ways of dealing with uncertainty, a trend that
had started with the development of stone tools two million years earlier. They
had the necessary behavioural templates that allowed them to herd animals,
domesticate them, plant the seeds of wild plants and improve them.
Moderns have continued the trends towards increasingly complex technolo-
gies and social systems, having conquered even the most inhospitable of en-
vironments (Gamble, 1993; Fernandez-Armesto, 2000). Cultural and social
diversity is the hallmark of human societies across the Earth today yet nobody
seriously attempts to equate these differences to biological differences. Nobody,
rightly, suggests that we are observing different species of humans. Yet, looking
at similar evidence of cultural and social diversity in the Pleistocene there are
still those who equate these to biological differences, the product of mutations
that made us something apart from the rest of nature. It is just another version
of the antiquated view of humans at the top of the evolutionary pyramid. If
anything, I hope to have shown in this book that we are the product of chance
and a great deal of luck. We are here because, in scrambling for survival in
208 Neanderthals and Modern Humans

the margins of the world of other humans, we became increasingly inventive
and kept ¬nding ways of hanging on and then taking over when others that had
been better adapted than ourselves vanished as circumstances changed. That
we are here today is the end result of a series of chance events that kept us in
the running. It could easily have gone the other way . . .
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