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documented fossils are those of the TD6 level of Gran Dolina in Atapuerca
(Spain) and the Ceprano (Italy) specimen which are older than 780 kyr (Par©s &
P©rez-Gonzales, 1995, 1999; Falgueres et al., 1999; Manzi et al., 2001).
The Gran Dolina specimens have been given speci¬c status “ H. antecessor
(Bermudez de Castro et al., 1997) “ and are considered to be ancestral to the
Neanderthals and H. sapiens. Other authors consider that H. antecessor was
a dead end and that the middle Pleistocene H. heidelbergensis was the ances-
tor instead (Hublin, 1998). I have discussed the dif¬culty of establishing the
real situation earlier in this chapter. The fate of the Neanderthals is the most
controversial of these events and one in which I will focus in Chapter 7.
Human range expansions, contractions and extinctions 53

5




4




3
Coefficient of Variation




2




1




0
-80 -70 -60 -50 -40 -30 -20 -10 0

Time (Myr)

Figure 3.3. Climate variability pattern during the last 70 Myr. The relationship is
statistically insigni¬cant. After Finlayson (2003).



In a paper published in 2003 (Finlayson, 2003), I attempted to correlate
the global climatic record during the past 800 kyr to the presence of hominids
in Europe. The Mediterranean Basin stood out as a buffer region between the
tropical African geographical core areas of Homo and the marginal regions
of northern and central Eurasia. The following time periods were studied at
different scales.


The period 70“0 Myr

The period 70“0 Myr (Miller et al., 1987; Berggren et al., 1995; Denton, 1999)
was analysed in 10 Myr periods at a resolution of 1-myr intervals. The period
was one of climatic cooling (Figure 3.2) and the last interval (10“0 Myr) was
the coolest of the entire sequence. Climate variability (Figure 3.3) reached a
maximum between 60 and 50 Myr and stabilised after 40 Myr at this scale.
Although variable, the climate in the 60“50 Myr interval was signi¬cantly
warmer than at any later stage.
54 Neanderthals and Modern Humans

-2.5

Warmer

-3.0




-3.5




-4.0
Mean δ18O




-4.5

Cooler

-5.0
-7000 -6000 -5000 -4000 -3000 -2000 -1000 0

Time (kyr)

Figure 3.4. Decrease in temperature during the last 6 Myr. Regression model y =
’4.3118 + 7.3 — 10 ’ 7x + 1.9 — 10 ’ 7 — 2 (2.6 — 10 ’ 11x)3 . The relationship is
statistically signi¬cant (R2 = 0.955, P = 0.016). After Finlayson (2003).


The period 6“0 Myr

The period 6“0 Myr (Denton, 1999) was analysed in 1-Myr periods at a reso-
lution of 100 kyr intervals. There was a statistically signi¬cant trend towards
climatic cooling (Figure 3.4) and the last interval (1“0 Myr) was the coolest
of the entire sequence. Climate variability (Figure 3.5) also increased signi¬-
cantly throughout the period. The interval 1“0 Myr was therefore the coolest
and most unstable of the sequence, followed by the 2“1 Myr and 3“2 Myr
intervals respectively.


The period 850“0 kyr

The period 850“0 kyr (Ruddiman et al.,1986) was analysed in 50-kyr periods at
a resolution of 5 kyr intervals. There was a weak but signi¬cant trend towards
Human range expansions, contractions and extinctions 55


14



12



10



8
Coefficient of Variation




6



4



2
-7000 -6000 -5000 -4000 -3000 -2000 -1000 0

Time (kyr)

Figure 3.5. Climate variability pattern during the last 6 Myr. Regression model y =
11.862 + 0.0044x ’ 1.2 — 10 ’ 6 — 2 + (1.1 — 10 ’ 10)3 . The relationship is
statistically signi¬cant (R2 = 0.538, P < 0.0001). After Finlayson (2003).



climate cooling (Figure 3.6). Climate variability appeared erratic at this scale
and there was no signi¬cant trend (Figure 3.7) although the most unstable
periods were in the latter half of the sequence. When mean temperature and
variability were combined (Table 3.1) it became clear that the last 200 kyr were
the coolest and most unstable of the sequence and that there was a trend from
warm/stable to cool/unstable from 850“0 kyr.


The period 90“0 kyr

The period 90“0 kyr (GRIP, 1993) was analysed in 5 kyr periods at a resolution
of 0.5 kyr intervals. There was no signi¬cant trend during this period (Figure 3.8)
but there were two clear intervals of cooling, around 75“55 kyr, that is related to
OIS 4, and from 45“15 kyr that is related to OIS 3 and 2. There was no trend in
56 Neanderthals and Modern Humans


-3.4

Warmer

-3.6



-3.8



-4.0



-4.2
Mean δ18O




-4.4

Cooler
-4.6
-1000 -800 -600 -400 -200 0

Time (kyr)

Figure 3.6. Relationship of temperature through time during the last 850 kyr. The
relationship is statistically insigni¬cant. After Finlayson (2003).


climate variability either (Figure 3.9), but there were unstable intervals clearly
related to the cooling events, at 80“65 kyr, 50“25 kyr and 20“10 kyr.
Table 3.1 summarises the presence in Europe of members of the genus Homo
between 850 and 0 kyr which may be related to the data in Figures 3.2“3.9. The
following periods were identi¬ed by Finlayson (2003).


The period 1.7 Myr“850 kyr

There were insuf¬cient data for analysis. The presence of H. ergaster in Dmanisi
(Georgia) (Gabunia et al., 2000), however, indicates that hominids had entered
Eurasia by then. A number of European sites claim human arrival on the basis
of presence of Mode 1 technology (Carbonell et al., 1999a; Oms et al., 2000)
and it seems very likely that hominids were present in southern Europe around
1 Myr.
Human range expansions, contractions and extinctions 57


30




20
Coefficient of Variation




10




0
-1000 -800 -600 -400 -200 0

Time (kyr)

Figure 3.7. Climate variability pattern during the last 850 kyr. The relationship is
statistically insigni¬cant. After Finlayson (2003).



The period 850“600 kyr

This period is marked by the presence in southern Europe of fossils that are
older than 780 kyr and may be ascribed to the form antecessor (Bermudez de
Castro et al., 1997; Manzi et al., 2001). These hominids appear to use Mode 1
technology (Carbonell et al., 1999a).



The period 600“250 kyr

This is marked by the presence in southern, western and north-western Europe
of fossils that are ascribed to H. heidelbergensis (Klein, 1999). These hominids
use Mode 2 technology. The later ones may be considered pre-Neanderthal
(Arsuaga et al., 1993).
Table 3.1. Summary of main climatic episodes described in the text and the major human events during the past 850 thousand
years (kyr)

Duration (kyr)

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