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that any human movement between Europe and Africa, if it took place, would
have involved a short sea crossing that, at its best, would have involved a series
of island hopping events with the longest sea crossing being of the order of
7km (Alimen, 1975; Giles Pacheco & Santiago P©rez, 1987). The Maghreb,
on the other side of the Strait of Gibraltar, would have been isolated by the
sea to the north and by the Sahara to the south (in cold and arid moments).
Human populations living in the Maghreb would have had the possibility of
16 Neanderthals and Modern Humans

contact with populations further south when the Saharan barrier broke down.
The question remains whether or not these North African humans had contact
with the Iberian populations (Simmons & Smith, 1991; Hublin, 1992).
Further east, Italy and the Balkans would also have been refuges for humans
during glaciations but their greater continentality and reduced surface area when
compared to Iberia would have made them less important. The Mediterranean
Sea would have been a barrier to contact with North Africa.
The next major refugium would therefore have been Turkey and the Levant.
The high mountains of Turkey would have limited human populations to the
narrow coastal strip during glaciations although reduced sea levels then would
have widened the area signi¬cantly (Finlayson et al., 2000a). The Levant would
have contrasted with Iberia and the Maghreb in that the absence of a sea barrier
would have brought Eurasian humans into more frequent contact with north-
eastern Africans. As with the Maghreb, Levant populations would have had
the opportunity of contact with Africans when the Sahara barrier broke down
although there may have been a regular contact thoughout via the Nile Valley
(van Peer, 1998).
Our knowledge further east is less complete but Crimea, areas around the
Caucasus and even further east have Mediterranean bioclimates even today and
are likely to have been refugia for Eurasian hominids (Finlayson et al., 2000a).
Finally, though not a part of this belt, the temperate regions of southern Africa
reveal similar characteristics to those of northern Africa. The absence of the
Sahara or of a sea barrier would, however, have permitted a greater degree of
contact with tropical African populations than would have been the case with
the Maghreb, the Levant or the northern shore of the Mediterranean.


The Great Eurasian Plain

The low-lying land that stretches almost without interruption from Britain to
the Bering Strait was covered in broadleaved forest in the west, steppe in the
east and boreal coniferous forest in the north. To the north were the glaciers and
ice sheets. Throughout the Quaternary these four elements grew and shrank at
the expense of the other depending on temperature and rainfall (van Andel &
Tzedakis, 1996). The milder, western, part was colonised by humans at a rela-
tively early stage, perhaps before half-a-million years ago (Stringer & Gamble,
1993; Klein, 1999). The open plains of eastern Europe and western and cen-
tral Asia were, on the other hand, colonised late. To my knowledge no human
ventured into these landscapes before the Moderns carrying an Upper Palae-
olithic tool kit at around 45“40 kyr bp (Bar-Yosef, 2000). Once colonised, the
open plains provided little physical resistance to dispersal. With the spread of
steppe westwards during the latter part of Oxygen Isotope Stage (OIS) 3 around
Biogeographical patterns 17

45“40 kyr came a steppe-adapted fauna and with them came the Upper Palae-
olithic people with an Aurignacian tool kit (Finlayson, 2003).


South, South-east and East Asia

The southern and eastern parts of Asia, below the Himalayan barrier, are distinct
enough to merit separate treatment. The key feature of this large area of land
is that hominids dispersing from Africa would have found it relatively easy
to penetrate in comparison to the areas to the north of the Levant. Access
would have been facilitated further during low sea levels when the coastal
belt widened and access may then even have been gained from the Horn of
Africa (Lahr & Foley, 1994). In addition, hominids dispersing in this direction
would have kept to low latitudes and therefore similar seasonal, climatic and
environmental regimes (Finlayson et al., 2000a). Thus eastern and south-eastern
Asia were colonised at a very early stage over 1 Myr ago (Klein, 1999). A fairly
constant ¬‚ow of genes between these Asian and their African counterparts
would thus be expected with fewer interruptions due to climatic shifts than on
the main Eurasian landmass or even due to the Saharan expansion. The main
factor countering such ¬‚ow would be the distance effect at the extremes. I have
proposed elsewhere (Finlayson et al., 2000a) that tropical South-east Asia, once
colonised, probably had continuity of human occupation until today. The long
persistence of Homo erectus to perhaps as recently as 25 kyr (Swisher et al.,
1996) would support this prediction. The question of what happened to these
populations is uncertain. Tropical South-east Asia therefore became the second
most important glacial refugium for hominids after tropical Africa itself and,
as with the Maghreb, Levant, southern Africa and Europe, temperate zones
of eastern Asia would have been colonised from here during mild conditions.
The difference with tropical Africa is that hominids could spread northwards
more easily given the absence of the Saharan barrier. I therefore consider south-
eastern and eastern Asia to have constituted a separate system from the African“
Eurasian system in terms of hominid biogeography once the latter was settled.
Gene ¬‚ow between the two would have been least at the extremes allowing for
a certain degree of separate evolution. The situation of India, which is largely
unknown, is of great interest in this respect.


The periphery

Two large land masses that lie on the periphery of the Eurasian“African systems
so far described, Australia and the Americas, were colonised late. Predictably,
Australia was colonised much earlier than the Americas (Thorne et al., 1999;
18 Neanderthals and Modern Humans

Bowler et al., 2003). This would be in keeping with the view proposed above that
the Asian tropics were, despite their distance from Africa, ecologically easier
to enter than the temperate north. Once in South-east Asia it was a question of
time before the sea barrier to Australia was crossed. Once achieved, as with the
Eurasian plains, a rapid expansion would be expected.
The key factor for the colonisation of the Americas would have also been the
arrival in eastern Siberia. This is the easternmost extension of the Eurasian Plain
which, as we have seen, was colonised late (around 42 kyr) and by Moderns
(Brantingham et al., 2001). As with these plains and Australia a rapid expansion
would be expected once the barrier of the Bering Sea was surmounted.


Mammalian herbivores

Although humans are omnivorous animals, and are likely to have been through-
out their evolutionary history, their relationship with herbivorous mammals
would have been a major factor that permitted the range expansion outside
the African tropics. Mammal meat would have been particularly important in
more northerly latitudes where many of the alternative food sources available
in the tropics would not have been found. It is therefore important to have an
understanding of the distribution of mammalian herbivores (Table 2.1).


Proboscideans (Order Proboscidea)

Proboscideans would have been a feature of the many landscapes inhabited by
humans in the Quaternary on most continents. In Africa, Proboscideans would
have included a late representative (Deinotherium) of the Deinotheriidae, a
Miocene family that survived until just over 1 Myr in east Africa (Shoshani
et al., 1996). These were specialised animals adapted to processing soft foliage
that had become rare in the early Pleistocene, apparently due to the spread of
grasslands and competition from Elephantoids in the Pliocene. The dominant
Proboscideans of Quaternary Africa were the Elephantidae. Three major genera
evolved in Africa. Loxodonta, the genus of the present-day African Elephant
L. africana, evolved in Africa at the end of the Miocene around 6.2“5.6 Myr
(Kalb et al., 1996) and remained essentially an African lineage (Todd & Roth,
1996). Loxodonta atlantica persisted into the mid-Pleistocene in Africa along-
side L. africana. Earlier African Plio-Pleistocene forms were L. adaurora and
L. exoptata (Kalb et al., 1996). The other two African genera are thought to
have shared a more recent common ancestor than each did with Loxodonta
(Kalb et al., 1996). Mammuthus appears in South Africa in the early Pliocene
Table 2.1. Main mammalian herbivore categories, their geographical distribution and habitat occupation in the Pleistocene
and the degree to which they were exploited by humans

Herbivore type Size class Africa MLB Eurasian Plain SE Asia Open Intermediate Closed Rocky Wetland Hunted Domesticated
a. Elephant L ++ ++ ++ ++ ++ ++ + ’ + + ’
b. Horse1 M ++ + ++ ’ ++ + ’ ’ + ++ ++
c. Tapir M + ’ ’ ++ ’ ’ ++ ’ ’ ’ ’
d. Rhinoceros L ++ ++ ++ ++ + ++ ’ ’ + + ’
e. Pig2 S/M ++ ++ + + + ++ + ’ ++ ++ ++
f. Hippopotamus L ++ + + ++ ’ + ’ ’ ++ + ’
g. Camel3 M/L ’ ++ + ’ ++ ’ ’ ’ ’ ’ +
h. Mouse Deer S ’ ’ ’ ++ ’ ’ ++ ’ ’ ’ ’
i. Giraffe L ++ + ’ ’ ’ ++ ’ ’ + + ’
j. Deer4 M ’ ++ ++ ++ ++ ++ ++ ’ ++ ++ +
k. Alcephalines M ++ ’ ’ ’ ++ + ’ ’ + + ’
l. Antelopes S/M ++ + + ’ ++ ++ ’ ’ + ++ ’
m. Bovids5 M/L ++ ++ ++ ++ ++ ++ + ’ ++ ++ ++
n. Caprids6 M + ++ ’ ’ ’ + ’ ++ ’ ++ ++
o. Duikers S ++ ’ ’ ’ ’ ’ ++ ’ ’ ’ ’
p. Other M ++ ’ ’ ’ + ++ ’ ’ ++ + ’

Type categories: a. all Proboscidea; Perissodactyla: b. Equidae; c. Tapiridae; d.Rhinocerotidae; Artiodactyla: e. Suidae; f. Hippopotamidae; g. Camelidae;
h. Tragulidae; i. Giraf¬dae; j. Cervidae; Bovidae: k. Alcelaphinae; l. Antelopinae; m. Bovinae; n. Caprinae; o. Cephalophinae; p. Hippotraginae, Peleinae,
Aepycerotinae, Reduncinae.
Domesticated species (from Diamond, 1997): 1, horse, donkey; 2, pig; 3, dromedary, bactrian camel, alpaca; 4, reindeer; 5, cattle, water buffalo, yak, Bali cattle,
mithan; 6, sheep, goat.
MLB: mid-latitude belt.
20 Neanderthals and Modern Humans

(M. subplanifrons). This species and M. africanavus of Central and North Africa
(the ancestor of M. primigenius) became extinct in Africa by the end of the
Pliocene and beginning of the Pleistocene (Haynes, 1991). The third genus,
Elephas, ¬rst appears as E. ekorensis in Kenya around 3.75 Myr (Kalb et al.,
1996). The genus, subsequently represented in Africa by E. recki and E. iolen-
sis, became extinct in that continent during the last glaciation (Todd & Roth,
1996).
The Mammutidae are absent from Plio-Pleistocene Africa but they per-
sisted in Eurasia where they arrived as African immigrants in the Mid “ Upper
Miocene (Tobien, 1996). Mammut borsoni appears in the Upper Miocene of
China. The species is common in Europe including the Mediterranean until
the early Pleistocene (Tobien, 1996). It is therefore possible that early homi-
nids dispersing into Asia encountered this species but it is less likely that
they did so in Europe. The Stegodontidae emerged in Africa in the early
Messinian (around 6.5 Myr) but had disappeared by the late Miocene (around
3 Myr). Migrations into Asia took place during lowered sea levels at the end of
the Miocene and the family thrived in Asia (Kalb et al., 1996). The genus
Stegodon is present in numerous localities in China, south and east Asia
from the late Miocene (around 5.5“5.3 Myr) where it persisted well into the
Pleistocene (Kalb et al., 1996). Among the Elephantidae, there was a ¬rst
African dispersal of Elephas into Eurasia in the middle Pliocene (around
3.5 Myr) and a second, of Elephas and Mammuthus, in the late Pliocene (around
2.5 Myr) (Todd & Roth, 1996). The ¬rst dispersal, into Asia, led to the evo-
lution of the present-day Asian Elephant, Elephas maximus, while the second
led to E. antiquus and E. falconeri in the middle Pleistocene, which became
extinct during the last glaciation. Mammoths (Mammuthus) dispersed rapidly
across Eurasia and North America in the late Pliocene. These evolved towards
progressively more open landscape forms: southern elephant M. meridionalis
in wooded steppe; steppe mammoth M. trogontheri in cool, dry steppe with
scattered trees; and woolly mammoth M. primigenius in cold, treeless envi-
ronments. The mammoth lineage evolved in response to the cooling of the
Pleistocene climate and the expansion of open habitats, although competition
from middle Pleistocene Elephas in the warmer, forested, areas of Eurasia may
have been a contributing factor (Lister, 1996). The last mammoths died out
in Siberia around 10 kyr (Martin & Klein, 1984) with an isolated population
on Wrangel Island in the Arctic Ocean persisting until 4 kyr (Vartanyan et al.,
1993).
North America saw the late survival of Proboscidean groups that had become
extinct much earlier in Africa and Eurasia. There were two immigrations into
North America across the Bering Strait, one in the middle Miocene (around 15.5
Myr) that involved Gomphotheriidae, Ambelodontidae and Mammutidae, and
a second in the Pleistocene that involved the Elephantidae (M. meridionalis
Biogeographical patterns 21

and M. primigenius) (Saunders, 1996). The mammoth dispersal may have
involved an early entry of M. meridionalis around 2.0“1.9 Myr and a second,
of M. primigenius, just before the start of the last glaciation (Dudley, 1996). Of
these radiations and subsequent evolution, Cuvieronius tropicus (Gomphotheri-
idae), Mammut americanus (Mammutidae), Mammuthus columbi, M. primige-
nius and M. exilis (Elephantidae) survived to the end of the Pleistocene (Fisher,
1996) and would have been contemporary with the human colonization of North
America.


Perissodactyls (Order Perissodactyla)

Horses (Equidae)
The earliest Equidae of the early Eocene were Holarctic in distribution. The
evolutionary trend across the Miocene and into the Pliocene was from wood-
land, through savannah to a predominance of grassland species (MacFadden,
1992). Two genera are of concern to us, having been potentially in contact
with humans in the Quaternary: Hipparion and Equus. The Hipparions were
three-toed grazers that ¬rst appeared in the middle Miocene of North America
around 15 Myr (MacFadden, 1992). The group dispersed rapidly and reached
the Old World via the Bering bridge by 11.5 Myr and radiated. This mid“late
Miocene expansion reached Africa. This genus reached its peak in the Pliocene
and subsequently entered decline, reputedly due to competition from Equus
(Anderson, 1984). In North America the genus went extinct in the mid-
dle Pliocene and the last Eurasian species reached the lower Villafranchian
(Gu©rin & Patou-Mathis, 1996). Potential contact with humans was therefore
only possible in Africa where the genus, adapted to living in herds in the sa-
vannahs (Anderson, 1984), persisted into the late Pleistocene with eight known
Plio-Pleistocene species (Bromage & Schrenk, 1999). The extinction in Africa
of the most advanced and widespread species H. libycum is attributed to the
radiation of the antelopes in the savannahs (Anderson, 1984).
The single-toed equine horses also radiated into North and Central America
but did not disperse into the Old World until the late Pliocene, when the genus
Equus (that had emerged in North America in the middle Pliocene “ E. simpli-
cidens) colonised Eurasia (E. stenonis) and Africa (MacFadden, 1992). Equus
radiated into North America, Eurasia and Africa during the Plio-Pleistocene,
the number of species depending on the authority, as species adapted to plains,
savannahs and certain mountain areas (Anderson, 1984). In North America
and Europe the genus became extinct at the end of the Pleistocene or just into
the Holocene (e.g. E. hydruntinus), persisting to today in Africa and Asia.
Humans would therefore have been in contact with Equus horses throughout
the Pleistocene.
22 Neanderthals and Modern Humans

Tapirs (Tapiridae)
Tapirs are semi-aquatic mammals of moist forests. It is unlikely that these
animals came into regular contact with humans on account of their geographical
distribution and habitat preferences. The climatic cooling and opening up of
habitats in the Pliocene and Pleistocene undoubtedly played a major role in
the range contraction of tapirs that were, for example, diverse in the European
Neogene. Only one species, Tapirus arvernensis, survived in Europe into the
middle Pleistocene (Gu©rin & Patou-Mathis, 1996). In North America, tapirs
persisted into the late Pleistocene, mostly in Florida (Anderson, 1984). Tapirs
did not occur in the Plio-Pleistocene of Africa. Tapirus indicus, known from
the middle Pleistocene (Tougard, 2001), survives today in South-east Asia and
there are three other species in Central and South America.

Rhinoceroses (Rhinocerotidae)
The oldest rhinoceroses have been found in the middle Eocene of North

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