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constrained by landscape pattern (Ferguson et al., 1998). Home-range size in
polar bears is related to the ratio of land to sea and to the seasonal ice cover
variation. Polar bears adjust the size of home range according to the amount
of annual and seasonal variation within the centre of the home range. Bears
experiencing unpredictable seasonal and annual ice respond by increasing their
home-range. The effect would be a reduction in the variation in seasonal and
annual ice that they experienced. These animals therefore make trade-offs be-
tween alternate space-use strategies. Large home ranges occur when there is
variable ice cover that is associated with more, but also more unpredictably
distributed, seals (Ferguson et al., 1999). In the case of baboons, predation,
group size, home and day range all increase with aridity (Dunbar, 1984). The
critical variables in their socio-ecology are food quality, food patchiness and
predictability. The proximate mechanism behind the relationship between for-
aging time and ecological variables in baboons is mediated through the impact
of climate (temperature and seasonality) on vegetation structure and food avail-
ability (Hill & Dunbar, 2002). In this book I emphasise the critical relationship
between human behaviour and vegetation structure and food availability, the
latter variables being strictly in¬‚uenced by climate. Such relationships appear
to explain, more widely, much of the variation in mammalian behaviour across
a range of spatial scales (Hill & Dunbar, 2002).
114 Neanderthals and Modern Humans

Foley (1992) proposed that the occupation of open habitats by the earliest
hominids meant that they were exploiting environments with greater uncer-
tainty, seasonality and patchiness, and that the expected adaptive response would
have been an increase in day and home ranges. A related outcome would have
been a larger annual range. The earliest hominids were found associated with
indicators of habitats with large patches of grassland and bushland. Such envi-
ronments promoted larger group sizes and extended foraging ranges in primates
(Foley & Lee, 1989).
The early members of the genus Homo continued the open habitat colonisa-
tion process and increased ef¬ciency with the use of tools, an increase in the con-
sumption of animal resources, increasing further day and home ranges, and also
group size (Foley & Lee, 1989; Foley, 1992). Male co-operation in food acqui-
sition became advantageous and the defence of females increasingly dif¬cult.
Co-operative defence of groups of females minimised loss. This enhanced male
kin relationships. The frequency, stability and intensity of male“female associa-
tions increased as a result of higher maternal reproductive costs due to increased
encephalisation, slower infant growth rates, delayed maturity/independence,
infants at additional risk of non-nutritional mortality due to predation, inter-
group encounters and infanticide (Foley & Lee, 1989). Such adaptability per-
mitted H. ergaster/erectus to colonise more temperate and seasonal climates
(Foley, 1992). Even so the distances involved in movement, as measured by raw
material transport, rarely exceeded 60 km in the Lower Palaeolithic (Feblot-
Augustins, 1990). By OIS 6“5 distances of 100 km were becoming increasingly
frequent in Middle Palaeolithic Europe and it is in the Upper Palaeolithic that
we observe the greatest increases, re¬‚ected by quantities of raw materials im-
ported from distant sources and in terms of stages of manufacture in which the
lithics were transported over these greater distances (Feblot-Augustins, 1993).
I shall interpret the signi¬cance of these increases below.
The ecomorphological characteristics of Moderns (Chapter 4) were a further
development of this continuing process and it enabled them to increase the use
of high quality resources, increase further the size of home ranges, group size
and structure. This was achieved by improving the ability to ensure hunting
and foraging success, thus turning unpredictability into predictability. Greater
longevity allowed for extension of information across generations and therefore
the recognition of lineage through space, thus structuring relationships between
groups over the long term. The ¬nal stage of the process, according to Foley
(1992), was the evolution of food production in the Neolithic.
I agree with Foley (1992) that these trends continued right up to the begin-
ning of the Holocene. Thus, the evolving Moderns in Africa during Stage 6
developed new skills, leading to better use of raw material, and new ecological
attributes like larger home ranges, day ranges, group size and dietary selectivity
Comparative behaviour and ecology 115

(Foley, 1989; Foley & Lahr, 1997) This, in my view, occurred when this popu-
lation was expanding and when the pre-Neanderthals would have had restricted
ranges in Europe because of the prevalent cold conditions. Foley (1989) has
proposed some ecological features of Moderns and these are characteristic of
patchy environments with high quality and predictable food: (a) a very large
home range; (b) a very large day range; (c) a large group size; (d) a high degree
of sub-structure within groups; and (e) dietary selectivity towards meat, which
occurs in large packages. In my view mobility strategies and home ranges are
principally dependent on the availability, dispersion and accessibility of food
resources. Availability of raw materials for tool manufacture, though undoubt-
edly important (Feblot-Augustins, 1993), would have played a subsidiary role
except in cases of food resource superabundance and lithic raw material local-
isation or scarcity.
Studies of contemporary hunter“gatherers lend support. Harpending & Davis
(1977) argued that ranges will be smaller where resources are in phase since
people can remain near sites of resource concentration. Increasing range in
areas with low patchiness does not increase diversity. Therefore larger ranges
will occur with patchy resources that are out of phase. Kelly (1983) showed
that hunter“gatherers in colder climates move a greater distance with each
residential move because resource patches are out of phase at low frequencies.
The Hadza and !Kung San live in arid savannahs. The !Kung live in areas where
important resources (water and plants) are patchy and out of phase. The Hadza
resources are more evenly distributed. The !Kung San have larger foraging
ranges and !Kung camps are located near water sources. Food resources may be
located many kilometres away. The Hadza can gather near the residential camp
(Cashdan, 1992). There is a considerable body of evidence linking Pleistocene
humans with wetlands (Nicholas, 1998). I have suggested elsewhere (Finlayson
et al., 2000a) that wetlands, as sources of concentrations of biomass especially
in seasonal environments, would have been highly signi¬cant in the evolution
of humans within tropical and Mediterranean zones and perhaps also in speci¬c
temperate situations.
Harpending & Davis (1977) have argued that if variance in total calories
between ranges is large, people should be clumped in large groups at the rich
locations. If variance is small, people should be more uniformly distributed and
in small groups. The former would be the case for Moderns and the latter for
Neanderthals. They also predict that: (a) if resources are distributed indepen-
dently of each other, calorie variance between ranges will be low and occu-
pations ought to be uniform; (b) if resources are correlated and in phase then
variation from place to place will be high and the settlement pattern will be
aggregated; and (c) if resources are out of phase then calorie variance between
ranges will be small leading to uniform occupation of large ranges.
116 Neanderthals and Modern Humans

According to Binford (1980), when resources are patchy on a scale larger than
the daily foraging range typical of boreal forest and arctic regions, the response
of human hunter“gatherers is to locate the residential camp at one resource
and send out small specialised task groups for other resources. These travel
long distances and remain at other resource locales for several days or weeks
(logistic mobility). Where resources are more evenly distributed a variety of
resources is available near camp and, therefore, whole residential group moves
as needed. Moves are shorter but more frequent (residential mobility).
A study of behavioural differences between Neanderthals and Moderns,
based on a small sample of sites in Israel, indicated that Modern Humans were
associated with seasonal patterns of resource (in this case gazelles Gazella
gazella) exploitation whereas Neanderthals apparently exploited the same re-
source all year (Lieberman & Shea, 1994). This led Lieberman & Shea (1994)
to interpret these data as indicative of Moderns having a circulating mobil-
ity pattern and Neanderthals a radiating mobility pattern. Circulating patterns
require seasonal movements of groups between a series of temporary resi-
dential camps while radiating ones require movement from a more permanent
(year-round) residential base camp to less permanent (seasonal) logistic camps
situated close to important resources. They attributed the differences between
Moderns and Neanderthals to morphological differences (Trinkaus, 1992) that
re¬‚ected their different mobility pattern that, in Neanderthals, required higher
daily expenditures of effort, and a higher level of hunting“gathering activity
(Lieberman & Shea, 1994; Lieberman, 1998). According to these authors Ne-
anderthals predominantly practised a radiating strategy, which required them to
hunt more frequently than Moderns, and Moderns practised a circular strategy.
They also accept that the two strategies need not have been mutually exclusive.
The problem that I see with these interpretations relates to scale. As we have
seen Moderns tended to be related with more open, homogeneous, landscapes
than Neanderthals and they required larger annual territories. They probably
practised a circular strategy, as proposed by Lieberman & Shea (1994), over
the annual cycle and over a large territory. However, at each seasonal stop,
they would have adopted a strategy closer to the radiating example with spe-
cialised groups performing different tasks, i.e. showing a high level of division
of labour. The Upper Palaeolithic people of northern Aquitaine in France, for ex-
ample, occupied winter settlements that were dedicated to the massive butcher-
ing of reindeer with alternative and functionally different sites in the summer
(Demars, 1998). The utlility of this behaviour is seen in the Upper Palaeolithic
exploitation of the Siberian subarctic or the central European Plain. These
colonisers organised specialised hunting from small camps that had links to
larger base camps, they had semi-subterranean dwellings, storage pits and art,
they economised on raw materials and transported some over long distances
Comparative behaviour and ecology 117

(Montet-White, 1994; Goebel, 1999). In other words they had the social, cul-
tural and ecological package that characterised the Moderns of the open plains
of Eurasia.
The key behavioural difference with the Neanderthals is that the Neanderthals
operated at a smaller spatial scale (Feblot-Augustins, 1993) “ they had smaller
annual territories, probably re¬‚ecting the more diverse resource-base available
in heterogeneous landscapes. Occupation of smaller annual territories would
have permitted small-scale movement patterns of either a circulating or radi-
ating type. Either way the effect would be to produce a picture of year-round
exploitation. Thus the Levantine evidence is in keeping with the model pro-
posed in this book. Working at a larger scale would have put premium on a
group™s ability to monitor the availability of distant resources, as indicated by
Lieberman & Shea (1994). Were the two tactics interchangeable? In my opinion
they were not for one simple reason “ the difference in morphology. The heavy,
robust, morphology of the Neanderthal would have precluded ef¬cient exploita-
tion of large territories. This may explain why robust archaic hominids never
ventured into the steppe environments of the Eurasian Plain. Where they were
close to it or on its margins, as in eastern Europe, they appear to have responded,
as we would expect, by increasing their changing mobility strategy (Feblot-
Augustins, 1993). Home range in mammals is generally predicted to increase
with habitat fragmentation and the home ranges of large species will be espe-
cially sensitive (Haskell et al., 2002). In orangutans, home range signi¬cantly
increases in response to coarse-grained patchiness (Singleton & van Schaik,
2001). We would also expect increasing home-range size in Neanderthals in
˜edge™ regions (bordering the MLB and the plains), such as south-west France,
in response to habitat fragmentation during periods of expansion of open veg-
etation. A more gracile morphology would have been far more ef¬cient over
larger areas. It may have sacri¬ced the close-quarter hunting strategy but this
may have been compensated for by technology. Technological change would
have made it possible for Moderns to be ¬‚exible in their use of large territory“
open environment vs small territory“heterogeneous environment strategies.
So it is the gracile Modern Human strategy that we observe for the ¬rst time
on the Russian Plain (Soffer, 1985). These people were entering unoccupied
territory but one that was rich in mammalian herbivores. Their way of coping
with the risks of colonising new territories may have a parallel in the subse-
quent colonisation of North America that I regard as part of the same process of
expansion into the mammal rich environments of Eurasia and North America.
The most suitable lifestyle in such new territories would have been one that
placed primary reliance on faunal rather than plant resources, as such resources
would be easier to locate. In addition, mammals would be available all year
and would be widely dispersed. Different species could be dealt with by similar
118 Neanderthals and Modern Humans

techniques. The process of adaptation to the plains continued throughout the
late Pleistocene and populations occupied distant regions. The late Upper Palae-
olithic hunters of north-east Asia were much more mobile than earlier Upper
Palaeolithic peoples of the region and they concentrated their subsistence on
a few key mammal species (Goebel et al., 2000). In situations of ¬‚uctuating
mammalian populations (due, for example, to climatic stresses) even the ex-
ploitation of large home ranges would have been insuf¬cient at times and a
higher-scale tactic, that of frequently changing home range so that the home
range exceeded the annual range, appears to have been the solution in the case
of Upper Palaeolithic North American palaeo-indians (Kelly & Todd, 1988;
Kelly, 1992). We can see how such a system could have equally applied to the
colonisers of the Eurasian Plain. If so it would be further evidence of the degree
to which risk was resolved by increasing the scale of operation.
Mobility is scale-dependent. To avoid confusion, I shall clarify my de¬nition
of mobility in Moderns and Neanderthals. Moderns, exploiting open environ-
ments, had large annual (home) ranges. At that scale they were highly mobile.
But their movement across this large home range was marked by periods of
relative sedentism with base camps close to rich resources. At this lower scale,
Moderns were more sedentary than Neanderthals. This needs to be quali¬ed
further. Division of labour in large groups, as would be expected in peoples
exploiting large home ranges, would have meant that some individuals would
have been sedentary close to the base camp while others would have ranged
more widely in search of food resources. In the case of the Neanderthals mobil-
ity would have been high at this lower scale and is likely to have been similar
among all individuals. The precocity of Neanderthal young (Dean et al., 1986;
Trinkaus, 1986) comes as no surprise. At the larger scale, however, we may
regard Neanderthals as more sedentary than Moderns as they covered a smaller
geographical area during the course of the annual cycle. An understanding of
the level of mobility of these populations is critical given that changes in mo-
bility patterns are known to trigger dramatic changes in food storage, trade,
territoriality, social and gender inequality, division of labour, subsistence and
demography (Kelly, 1992).
The differences in spatial dispersion and mobility of hominids in heteroge-
neous landscapes (Moderns and Neanderthals) and homogeneous landscapes
(mainly Moderns) re¬‚ect wider patterns. According to Geist (1977) oppor-
tunism in animals may be of two kinds. One is of a highly mobile nature that
involves the exploitation of small food patches, as these become available, and
subsequent movement on. This small-scale opportunism, that I equate with
Neanderthals, ties individuals much less during reproduction and favours a
small number of large, well-developed, highly mobile young that can follow
the parent at an early stage. This is exactly what we observe in Neanderthals.
Comparative behaviour and ecology 119

The second type also involves a mobile form but only until a large food resource
is found, adequate for maintenance and reproduction. Since reproduction can
be maximised there is selection for a maximum number of young and these
disperse when they reach near-adult size. The small-scale opportunists, like the
Neanderthals, are at the K-end of the selective strategy whilst the large-scale
opportunists, such as the Moderns, are at the r-end of the range.


Technology

To understand technology and technological change we must relate it to eco-
logical function (Kuhn, 1995). Foley (1989), for example, has proposed that
the development of technology that allows predation from a distance, e.g. the
use of projectiles, will provide the hunters with a major advantage. He tries
to relate this to the very early appearance of blade technology in Africa. Prey
can be unpredictable in distribution and success of capture, particularly in open
environments where predators have the added disadvantage of not being able
to get as close to prey as in more vegetated areas. Mechanisms that reduce
this unpredictability will be favoured. Fitzhugh (2001) has recently provided
a theoretical framework, using mechanistic principles of Darwinian evolution,
that helps in our understanding of the observed technological changes in the
Palaeolithic. Fitzhugh (2001) proposes a model of technological change that
simply requires that individuals have the cognitive ¬‚exibility to assess their
risk sensitivity and modify technological behaviour appropriately. Conditions
of greater risk sensitivity should generate more inventive behaviour, especially
at times of economic crisis. Since there is no guarantee of success for a nov-
elty, the chances of replication of a novel behaviour will increase as inven-
tive behaviour increases in response to greater risk sensitivity. As population
density increases so we would expect that there would be more people avail-
able to generate successful novelties and that these should spread more rapidly
due to greater facility of cultural transmission. The rate of technological change
would therefore increase. This model predicts the changes observed in the
Palaeolithic, including the slow early rate of technological innovation and its

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