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can be mapped through the Pleistocene (Foley, 1992).
I view the increase in symbolism as a re¬‚ection of the increasingly sophis-
ticated social systems of the people who entered environments such as those
of the Eurasian Plains. A correlation between the abundance of opportuni-
ties for social learning and the size of the local cultural repertoire may be an
ancient feature, present in the great apes, that may have existed for at least
14 Myr (van Schaik et al., 2003). We have seen how the behaviour of Moderns
in the Eurasian Plain would have been correlated with increased opportunities
for social learning so it is not unexpected to ¬nd a concomitant jump in ob-
served cultural, including symbolic, diversity without recourse for explanations
requiring increased cognitive capacity. It is also possible that many of the cul-
tural elaborations observed in the highly unpredictable conditions of the late
Pleistocene may be a response to such conditions (Dunnell, 1999; Dunnell &
Greenlee, 1999; Hamilton, 1999; Kornbacher, 1999; Madsen et al., 1999).
Humans frequently return to a central place when they forage. Central-place
foraging varies along a continuum and involves special travel costs, including
carrying time. It also involves deferment of consumption (Kaplan & Hill, 1992).
Symbolic communication then becomes important in humans as it is used to
increase the information available to foragers in two ways: (a) by increasing the
sample size of resource distributions and characteristics; and (b) by providing
information on prey or patches that foragers have never exploited (Kaplan &
Hill, 1992).
Hunter“gatherers (e.g. !Kung San) maintain kin ties across a region. When re-
sources are scarce people typically respond by visiting kinsmen located in a tem-
porarily well-favoured area (Cashdan, 1992). This may be a kind of reciprocal
Comparative behaviour and ecology 127

altruism (Trivers, 1971) that constitutes another kind of buffering in unpre-
dictable environments. Humans may have developed co-operation mechanisms,
acting as environmental buffers, by maximising inclusive ¬tness in kin-based
groups (Hamilton, 1964) or through reciprocal altruism (Trivers, 1971) in sit-
uations in which the individuals in groups were in regular contact over long
time periods. Such co-operation may also evolve among unrelated agents who
are suf¬ciently similar to each other in some arbitrary characteristic (e.g. a
marking) but who do not reciprocate (Riolo et al., 2001; Roberts & Sherratt,
2002). Although such co-operation is predicted for organisms with a rudimen-
tary ability to detect environmental signals without need of memory of past
encounters, we can see how it could also evolve among large groups of humans
with irregular contact. Recent models of large interacting communities of play-
ers on spatial grids indicate that voluntary interactions promote co-operation
(Szabo & Hauert, 2002). To achieve a stable regime of all-out co-operation
other mechanisms, such as punishment, are required (Henrich & Boyd, 2001;
Fehr & Gachter, 2002). Image scoring (the way an individual is viewed by the
group) also promotes co-operative behaviour in situations where direct reci-
procity is unlikely (Wedekind & Milinski, 2000). Whilst the social structure of
Neanderthals would have permitted co-operation of a kin or reciprocal type,
the larger networks of the Moderns would have permitted a greater range of
mechanisms to come into play even among unrelated individuals or those not
in regular contact.
I propose that the evolution of strong and complex patterns of social be-
haviour was a long-term process that had its roots and subsequent development
in the increasing adaptation to a plains existence. Such an evolution would
have led to increasing group and home-range size that generated the need for
within-group division of labour. With this came the need for groups to split for
increasingly longer periods. Social bonding and information exchange became
increasingly vital. The template for the evolution of a complex social system
that would include language, symbolism and art was set in the conditions that
were experienced most frequently by Moderns and less so, because of habitat
differences, by archaics such as the Neanderthals.
The fact that Neanderthals lived in the heterogeneous landscapes of the
Mediterranean bioclimates meant that they were able to obtain suf¬cient re-
sources within small home ranges (Mellars, 1996; Gamble, 1999). This sys-
tem, which was linked to a highly omnivorous diet, did not lend itself to the
social innovations that were a feature of the peoples of the plains (Gamble,
1999). Anderson & Franks (2001) distinguish between groups and teams in
animal societies. Groups are associated with small societies in which group
tasks require the simultaneous performance and co-operation of two or more
individuals for successful completion. Teams, on the other hand, are more likely
128 Neanderthals and Modern Humans

to be found in larger, more complex, societies with a division of labour. Spe-
cialisation, learning and overall enhanced performance ef¬ciency enhance the
ergonomic ef¬ciency of the team (Anderson & Franks, 2001). In this respect I
see Modern societies behaving more like teams, based on individual recogni-
tion, acting as cliques with an element of trust among individuals and exposed
to potential cheats. Neanderthal societies may have behaved more like groups.
Neanderthals probably lived most of their lives in small family groups, in which
the individuals would have been in close contact throughout their lives, within
an intimately well-known home range, and with little within-group division of
labour. This does not imply any Modern superiority. It simply indicates that
these were adaptations to improve ef¬ciency in wide-ranging people, adapta-
tions that may not have been necessary in the environments exploited by the
Neanderthals.


Language

Lieberman (1989) suggested that Neanderthals were de¬cient with respect to
their linguistic and cognitive capacity, their speech communications being nasal
and subject to perceptual errors. Stringer & Gamble (1993), discussing the
probability that Neanderthals had language, concluded that the Neanderthals
did have at least a rudimentary form of language but that it was probably
simple in construction and restricted in its range of expression. These authors
recognised, however, that the ability to create and understand language was
a function of the brain rather than of the vocal tract, which presumably they
considered to be related to speech. The lack of understanding of the Neanderthal
brain was recognised as a problem. Aiello & Dunbar (1993) considered that
by 250 kyr the hominid brain had reached a size that could sustain group sizes
of 150 people and that such group sizes required a gossip (instead of a full
symbolic) language. Buckley & Steele (2002), however, did not ¬nd a link
between the management of af¬liative ties in large co-residential social groups
and language. Instead, they considered that life history strategy was the prime
mover, within the context of co-operative foraging and provisioning, for spoken
language abilities. Speech adaptations, according to this view, co-evolved with
life history strategy.
Language, as a social adaptation, allows individuals to transfer and receive
information about people, objects and places not present, and to manage rela-
tionships with other individuals (Buckley & Steele, 2002). Narrative devices
would have served to communicate foraging knowledge (Sugiyama, 2001).
Gamble (1999) considered that Neanderthals had an advanced form of com-
munication that was, however, only directed towards the negotiation of their
Comparative behaviour and ecology 129

intimate networks. In a comparative study of Middle and Upper Palaeolithic
technology, Chazan (1995) could ¬nd no evidence to support the hypothesis
that the transition was related to the development of language. Ohnuma et al.
(1997), on the other hand, inferred experimentally that spoken language was
not indispensable for Levallois ¬‚ake production in the Middle Palaeolithic. In
my view it is inconceivable to think of Neanderthals without language. Recent
work with bonobos Pan paniscus reveals the ability of these apes to work with
a, limited, language (Savage-Rumbaugh & Lewin, 1994). Tonal melodies form
musical gestalts in rhesus monkeys, as they do in humans, indicating that there
is similar transduction, storage, processing, and relational memory of musical
passages in monkeys and humans (Wright et al., 2000). Large-brained hominids
would have had far greater capacities, especially the Neanderthals. This does
not imply that Neanderthals and Moderns had identical forms of language and
speech. Buckley & Steele™s (2002) explanation for the evolution of language via
intensely negotiated co-operation within small stable groups based on family
and kinship ties would ¬t the Neanderthal model and thus advocates a pre-
Modern evolution. The different lifestyles of Neanderthals and Moderns and
the manner in which Moderns expanded their scale of operation, with tempo-
rary absences of individuals from the group becoming a regular feature, would
have placed a strong pressure on the re¬nement and further development of
any language and speech capability that existed in archaic forms. The dating of
the ¬xation of the mutation in the FOXP2 gene, that is involved in the devel-
opmental processes that culminate in speech and language (Lai et al., 2001),
to within the last 200 kyr (Enard et al., 2002) is in keeping with this scenario.
These re¬nements could evolve by a Baldwin effect (Simpson, 1953), language
emerging through self-organisation and continued through cultural transmis-
sion. Individual characteristics that were advantageous to language production
and comprehension would then be ¬xed by natural selection (Buckley & Steele,
2002).


Neanderthal“Modern ecological and behavioural differences

What conclusions can we draw with regard to differences in behavioural ecol-
ogy between Neanderthals and Moderns? The main conclusion is that the two
forms were highly intelligent and behaviourally plastic and capable of respond-
ing dynamically to ecological circumstances. The dehumanised portrayal of
the Neanderthals is not consistent with the evidence of a sophisticated hominid
having the root of many of these behavioural patterns in pre-Neanderthal pop-
ulations (Hayden, 1993). It is therefore not surprising to ¬nd that there is so
much overlap in the food consumed and the way in which it was procured.
130 Neanderthals and Modern Humans

Neanderthals were well adapted to the nature of the terrain that they exploited.
Geographically, it was the MLB from Portugal in the west to the mountains of
Central Asia in the east (Chapter 3). This was the geographical area of contin-
uous occupation (Gamble, 1999; Finlayson et al., 2000a) of the Neanderthals
and their predecessors (Figure 5.3). So for a period from the establishment of
the pre-Neanderthals, perhaps around 500 kyr (Chapter 4), until their extinc-
tion around 30 kyr they adapted to the heterogeneous landscapes of this MLB,
expanding northwards at the western end of the range when milder conditions
removed the open steppes from north-west Europe (Chapter 6). I argue here
that the robust morphology of the Neanderthals, typical of Middle Pleistocene
hominids, suited them well but also prevented niche expansion to include open
plains environments that required large annual home ranges.
In the mosaic landscapes of the Levant the Moderns occupied the range of
available habitats but their mobility regime appears to have been very differ-
ent from that of the Neanderthals, exploiting resources seasonally, implying a
greater annual home range. In the Levant we observe a natural laboratory in
action. We have two morphological types of human, behaviourally similar and
plastic but exhibiting differences in the way they utilised the landscape. Since
both were regionally present for a period of up to 60 kyr (from 100 to 40 kyr ago)
we can infer that climatic and environmental ¬‚uctuations, sometimes favouring
one strategy, at other times the other, prevented one form succeeding over the
other. We would expect that similar patterns would be observed wherever the
two forms were present in terrain that included heterogeneity and plains, as in
the Levant. Another such area would be the northern edge of the central Asian
mountains with the Russian Plain (Soffer, 1985, 1994). The difference here is
the much greater extent of the plains and the huge herbivore biomass resource
available. Such a situation awaited a hominid that could break away from the
shackles of the territorial exploitation patterns that had characterised Eurasian
Middle Palaeolithic hominids. It is unlikely that the Neanderthals would be the
ones to suddenly exploit this resource, which would have been at their doorstep
for millennia. Gene ¬‚ow between the populations in the heterogeneous belt
and hypothetical breakaway populations on the plains would have limited mor-
phological change, the necessary base for the successful exploitation of the
plains.
A similar situation occurred to the Neanderthals in the west, in areas such
as south-western France, Italy and around the Carpathians. These were edge
areas between heterogeneous landscapes and the plains. During the cold and
arid events of OIS 3 (Chapter 6) the steppic environments expanded westwards.
Neanderthals in these edge areas had to adapt to the changing circumstances
or face local extinction. The evidence seems to point to behavioural adaptation
in the form of transition industries (d™Errico et al., 1998; Mellars, 1999) that
Comparative behaviour and ecology 131

appear to re¬‚ect changing hunting tactics and even an increase in home range
(Feblot-Augustins, 1993). Morphology could not change rapidly enough and
the Neanderthals disappeared after a few thousand years.
Returning to central Asia, we have no evidence of major climatic or physical
barriers that would have separated plains Middle Palaeolithic hominids from
those in the adjacent heterogeneous belt. Instead, we have a morphologically
gracile candidate in the area as from 100“60 kyr, with an ability to exploit plains
environments. Although we cannot fully discard a local plains adaptation by
Neanderthals, as might be expected under stressful situations in the presence
of resource heterogeneity (Parsons, 1993), my view is that it was the early
Moderns that penetrated into central Asia, operating at larger spatial scales
and evolving increasingly sophisticated behavioural patterns in ecotonal areas
between the central Asian belt and the Russian Plain. The territorial exploitation
system and its correlates, that included living in large groups, intense social
binding mechanisms and mechanisms of food storage would have provided the
launch pad for the conquest of the Russian Plain. Morphology was no longer
a constraint. Behavioural adaptations, not dependent on slow genetic change,
catapulted the colonisation. This process is in keeping with the observation
that innovation of behavioural traits is especially likely during periods of stress
(Parsons, 1993). That events during the last glacial cycle introduced stress
(Chapter 6) is beyond doubt. Behavioural plasticity, allowing for changes in
social behaviour, may be widespread in animals (e.g. Davies, 1976) and may be
the optimal response to stresses that occur at higher frequencies than generation
time. We detect this as the rapid spread of the Aurignacian people across the
Eurasian Plains that I view as a classic form of ecological release (Cox &
Ricklefs, 1977). I will examine this expansion in detail in Chapter 7 after I have
described the climatic and environmental changes that affected the world at this
critical time.
Kaplan et al. (2000) have proposed four characteristics of humans: excep-
tionally long life span; extended period of juvenile dependence; support of
reproduction by older post-reproductive individuals; and male support of re-
production through the provisioning of females and their offspring. These at-
tributes, along with extreme intelligence, are co-evolved responses to a dietary
shift toward high-quality, nutrient-dense, dif¬cult-to-acquire resources. If this
is indeed the signature throughout the course of human evolution, we would
expect its maximal expression in those hominids that ventured onto open plains
environments and specialised on large mammalian herbivore meat.
Group size is a function of the size of the neocortex in primates (Dunbar,
1992). The relationship may be the result of limits imposed by the number of
neocortical neurons on the information-processing capacity of organisms that
would set a cap on the number of relationships that an individual can monitor
132 Neanderthals and Modern Humans

simultaneously. Since group size will be determined by the ecological char-
acteristics of the environment occupied, new environments that require larger
groups will only be successfully colonised after the evolution of larger neo-
cortices (Dunbar, 1992). The recent discovery of microcephalin, a gene that is
expressed in the developing cerebral cortex of the foetal brain, may provide
insights into the proximate mechanisms of neocortex development and evo-
lution (Jackson et al., 2002). The enlarged neocortex of Moderns when com-
pared to archaic forms (Stringer & Gamble, 1993) may be an additional feature
that promoted the rapid expansion into plains environments. In this scenario,
the observed behavioural characteristics of Upper Palaeolithic Moderns on the
Eurasian Plain would re¬‚ect a quantitative, but not a qualitative, catapulting of
this co-evolutionary process.
The time frame for the emergence of uniquely human cognitive skills is be-
tween 2 Myr and 0.3 Myr, probably closer to the youngest age (Tomasello,
1999). According to this author the emergence may have been marked by a sig-
ni¬cant genetic event but one that did not specify the detailed outcomes we see in
humans today. Instead, it opened the way for new social and cultural processes
that subsequently, with no further genetic events, created the distinctive fea-
tures of human cognition. In my view, and in keeping with Tomasello™s (1999)
time frame, the ˜signi¬cant™ event probably pre-dated the Modern“Neanderthal
split. This would have permitted a multiplicity of subsequent outcomes. When I
compare the Neanderthals and the Moderns I can only come to one conclusion “
they expressed two alternative forms of being human. It is only the difference
in morphology that, in the end, marked the difference by restricting or releas-
ing behavioural patterns that ultimately permitted the survival of one and the
extinction of the other in a randomly ¬‚uctuating world.


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