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Time period of favourable (+)/ % of Potential Homo
(kyr) Climate OIS unfavourable (’) OIS period pattern Homo type Mode

?
850“800 wu 22“21 20 (+) 40 (Persistence) 1
800“750 WS 21 50 (+) 100 Colonisation antecessor 1
750“700 CS 20“18 37 (’) 74 Extinction [52%]
?
700“650 ws 18“16 30 (+) 60 (Colonisation/
Persistence)
650“600 CS 16“15 30 (’) 60 Extinction [100%]
600“550 WS 15“14 35 (+) 70 Colonisation heidelbergensis 2
heidelbergensis
550“500 WU 14“13 46 (+) 92 Persistence 2
500“450 CS 13“12 28 (’) 56 Extinction [35%] ? heidelbergensis 2
heidelbergensis
450“400 wU 12“11 23 (+) 46 Persistence 2
heidelbergensis
400“350 WU 11“10 38 (+) 76 Persistence 2
heidelbergensis
350“300 Wu 10“8 36 (+) 72 Persistence 2
heidelbergensis
300“250 wu 8 0 (+) 0 Persistence 2
250“200 Ws 8“7 45 (+) 90 Colonisation/ heidelbergensis/ 3
Persistence helmei
? neanderthalensis
200“150 Cs 7“6 36 (’) 72 (Extinction) [22%] 3
neanderthalensis
150“100 CU 6“5 28 (+) 56 (Persistence/ 3
Extinction)
100“50 CS 5“3 12 (’) 24 Extinction [43%] neanderthalensis 3
neanderthalensis/
50“0 CU 3“1 11 (’) 22 (Persistence/ 4
sapiens
Extinction) [100%]

˜Climate™ column: w, warm; c, cold; s, stable; u, unstable; and capitals refer to major episodes. OIS, oxygen isotope stage. ˜Potential Homo pattern™ column:
percentages behind extinction events are the duration of the extinction event divided by the duration of the preceding favourable event — 100.
Data in bold: these are considered by author to be most signi¬cant and are highlighted in the text.
Source: After Finlayson (2003)
.
Human range expansions, contractions and extinctions 59

-34


-35


-36


-37


-38


-39


-40
Mean δ18O




-41

-42
-100 -80 -60 -40 -20 0

Time (kyr)

Figure 3.8. Relationship of temperature through time during the last 90 kyr.
Regression model y = ’32.754 + 0.4679x + 0.0087x2 + (4.7 — 10 ’ 5x)3 . The
relationship is statistically signi¬cant (R2 = 0.678, P = 0.001). After Finlayson
(2003).




The period 250“150 kyr

This is marked by the presence of pre-Neanderthal fossils and the use of Mode
3 technology. Foley & Lahr (1997) have proposed that Mode 3 arrives from
Africa with a new species “ H. helmei.



The period 150“50 kyr

This is marked by the presence of the ˜classic™ Neanderthals (Klein, 1999) with
Mode 3 technology.
60 Neanderthals and Modern Humans


7


6


5


4
Coefficient of Variation




3


2


1


0
-100 -80 -60 -40 -20 0

Time (kyr)

Figure 3.9. Climate variability pattern during the last 90 kyr. Regression model
ln(y) = 1.3493 + (11.1463/x). The relationship is statistically signi¬cant (R2 =
0.599, P < 0.0001). After Finlayson (2003).




The period 50“0 kyr

This is marked by the presence of the last Neanderthals and their extinction
between 40 and 30 kyr (Klein, 1999). The Neanderthals continue with Mode
3 technology but, towards the end, appear to adopt (Mellars, 1999) or invent
(d™Errico et al., 1998) Mode 4-like technology (Chapter 5). The period is also
marked by the arrival of Moderns and Mode 4 technology.
There has therefore been a consistent global cooling from 70“0 Myr. The last
1 Myr, the period of the colonisation of Europe by hominids, has been the coolest
and most variable of all. The temperature and variability pattern within the last
850 kyr appears closely related to the pattern of hominid distribution (Table
3.1). Finlayson (2003) divided the last 800-kyr period into 50-kyr intervals
and allocated to each the probability of colonisation of Europe from Africa or
extinction of Homo populations in Europe.
Human range expansions, contractions and extinctions 61

Colonisation events

Mithen & Reed (2002), using computer simulations, also found that the highest
probabilities of colonisations from Africa were before 1.7 Myr. Three post-1
Myr colonisation events were predicted by Finlayson (2003), all during the only
warm and stable periods in the sequence.


800“750 kyr

This interval re¬‚ects the warm and stable conditions of OIS 21 that lasted for
the entire 50 kyr period and coincided with the presence in Europe of the ¬rst
undisputed hominids (H. antecessor) at Atapuerca (Pares & P©rez Gonzales,
1995, 1999; Falgueres et al., 1999; Carbonell et al., 1999b) and Ceprano (Manzi
et al., 2001) with Mode 1 technology. The earlier presence of hominids over
1 Myr in Europe was not discarded and would be related to warm and stable
conditions preceding the climatic oscillations that commenced around 850 kyr
with OIS 22.


600“550 kyr

This interval re¬‚ects the warm and stable conditions of OIS 15 that lasted
for 35 kyr. The predicted colonisation events coincide with the presence in
Europe of hominids attributed to H. heidelbergensis and the arrival of Mode 2
technology.


250“200 kyr

This interval re¬‚ects the warm and stable conditions of OIS 7 that lasted for
45 kyr. This predicted colonisation event coincided with the arrival of Mode 3
technology and, according to Foley & Lahr (1997), H. helmei. The last coloni-
sation, by Moderns with Mode 4 technology, is not predicted and is discussed
below.



Extinction events

Four extinction events were predicted. These were the four cold and stable
events in the sequence.
62 Neanderthals and Modern Humans

750“700 kyr

This interval re¬‚ects the cold and stable conditions of OIS 20“18 that lasted for
37 kyr.



650“600 kyr

This interval re¬‚ects the cold and stable conditions of OIS 16 that lasted for
30 kyr. It seems highly unlikely that the H. antecessor populations that occupied
the southern fringe of Europe would have survived two such major events so that
my view is that these populations were probably not ancestral to later European
populations of Homo.



500“450 kyr

This interval re¬‚ects the cold and stable conditions of OIS 12 that lasted
28 kyr. The fossil evidence is of insuf¬cient resolution to support or reject this
prediction. Given, however, that this event was of relative short duration and
that it followed a lengthy period of colonisation and persistence, it is possible
that the H. heidelbergensis populations with Mode 2 that had colonised north-
western Europe were large enough to survive the crisis in southern European
refugia. The subsequent presence of hominids attributed to H. heidelbergen-
sis in Europe (Klein, 1999; Manzi et al., 2001) would seem to bear this out.
The fact that there is no predicted colonisation event after this, and therefore
no new population that would account for the European fossils, would seem
to lend further support to the persistence of H. heidelbergensis past the OIS
12 crisis.



100“50 kyr

This interval re¬‚ects the cold and stable conditions of OIS 4 that lasted for 12 kyr.
This extinction event is slightly earlier than the extinction of the Neanderthals
(40“30 kyr). The short duration of this event was clearly insuf¬cient to cause
the Neanderthal extinction but may have depressed the populations to such a
level that they became extinct shortly after (Finlayson et al. 2000a).
Human range expansions, contractions and extinctions 63

Intervening periods

There were ¬ve intervening periods between predicted colonisation and extinc-
tion events (Table 3.1):



700“650 kyr

This interval coincides with OIS 17 that lasted 30 kyr, was weakly warm and
stable and was sandwiched between two major cold events. Assuming the H.
antecessor populations became extinct in the preceding stage then there is a
slight possibility of a small colonisation during this period. Alternatively, this
stage could have supported surviving H. antecessor populations that then went
extinct in OIS 16. Thirdly, it is possible that there were no hominids in Europe
at this time. These options must remain open on present evidence.



550“500 kyr

This interval coincides with OIS 13 that lasted 46 kyr and was a warm but
unstable period. It was therefore a long period, following the colonisation by
H. heidelbergensis with Mode 2 technology, that would have allowed the per-
sistence of these populations.



450“250 kyr

This interval coincides with OIS 11“9 that lasted for 97 kyr and was also a
warm but unstable period. Its length would have permitted the persistence of
H. heidelbergensis populations that survived OIS 12.

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