The Dawn of Human Culture (16 page)
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Clacton &
Swanscombe
Schöningen
Boxgrove
Bilzingsleben
Mauer
Menez-Dregan
St. Acheul
Steinheim
Vértesszöllös
Dmanisi
Terra Amata
Atapuerca
Arago
Ceprano
from Africa to
Torralba
Petralona¯
Europe across
& Ambrona
the Bosporus or
Dardanelles
Berekhat Ram
'Ubeidiya
FIGURE 5.1
The approximate locations of European sites mentioned in the text.
The contrast with Africa and southern Asia is stark, and it implies that Europe posed special obstacles to early human settlement, particularly during glacial intervals. The first permanent occupants of Europe were late Acheulean hand axe makers, who spread from Spain and Italy on the south to southern England on the north about 500,000
years ago. Occasional human fossils like those from Petralona, Greece, and Arago, France, suggest that the hand axe makers resembled their African contemporaries, and the Europeans probably descended from an expanding African population that brought the late Acheulean Tradition to Europe. For the sake of convenience, we assign this population and its first African and European descendants to the species
Homo heidelbergensis
. We introduced
heidelbergensis
in the last chapter, where we pointed out that the “type” specimen is a massive lower 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 135
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jaw found in 1907 at the Mauer sand quarry near Heidelberg, Germany.
Associated animal species indicate that the jaw is about 500,000
years old.
Homo heidelbergensis
shared many primitive features with
Homo ergaster
and
Homo erectus,
including a large, forwardly projecting face, a massive, chinless lower jaw with big teeth, large browridges, a low, flattened frontal bone (forehead), great breadth across the skull base, and thick skull walls (Figure 5.2). At the same time, it departed from both
ergaster
and
erectus
in its much enlarged brain, which averaged over 1200 cubic centimeters (cc) (compared to about 900 cc for
ergaster
and 1000 cc for classic
erectus
), in its more arched (versus more shelf-like) browridges, and in the shape of its braincase, which was broader across the front, more filled out at the sides, and less angular in the back. Like
erectus
,
heidelbergensis
probably evolved from expanded braincase
flat, receding
forehead
massive
browridge
0
5 cm
forward
projection
0
2 in
of the
upper
Arago 21 and 47
jaw
face partially
distorted in the
ground
FIGURE 5.2
A partially reconstructed skull from Arago, France, assigned here to
Homo heidelbergensis
(drawn by Kathryn Cruz-Uribe from photographs). (Copyright Kathryn Cruz-Uribe.) 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 136
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ergaster,
and in its anatomy and its geographic distribution, it is a plausible common ancestor for the Neanderthals (
Homo neanderthalensis
) who appeared subsequently in Europe and for modern humans (
Homo
sapiens
) who evolved later in Africa.
* * *
may have been the first human species to gain a permanent foothold in Europe, but it was not the first to try. Cave deposits in the Sierra de Atapuerca near Burgos, northern Spain, reveal an earlier, if fleeting attempt, and ancient lake deposits at Ceprano near Rome, central Italy, may record another.
Despite its name, the Sierra de Atapuerca is not a mountain range, but a large limestone hill that is literally honeycombed with caves.
Two of these—the Sima de los Huesos (“Pit of the Bones”) and the Gran Dolina (“Large Depression”)—are so remarkable that the prestigious
Journal of Human Evolution
devoted a thick special issue to each, in 1997 and 1999 respectively. The Gran Dolina stands out, because it has provided the most compelling evidence for human presence in Europe before 500,000 years ago. The Sima is famous for a mass of human fossils that document the local, European evolution of the Neanderthals from
heidelbergensis
.
The Gran Dolina contains 18 meters (60 feet) of sandy, rocky deposits first exposed in a now-abandoned railway trench at the turn of the twentieth century. Excavations that began in 1976 and then accelerated after 1993 show that artifacts and fragmentary animal bones are concentrated in six discrete layers. The layer that interests us here is the second from the bottom, known as TD6, which has provided more than 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 137
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ninety fragmentary human fossils and 200 flaked stone artifacts. An horizon that lies roughly 1 meter (3 feet) higher records the shift in global magnetic polarity from the last (Matuyama) reversed chron to the present (Brunhes) normal chron (Figure 3.3 on p. 68). This means that TD6 must be older than 780,000 years. The Electron Spin Resonance dating method brackets the TD6 fossils and artifacts between 857,000
and 780,000 years ago, and bones of long-extinct rodent species support an equally great age. With admitted uncertainties in mind, the excavators conservatively place TD6 at about 800,000 years ago.
The TD6 human fossils include eighteen skull fragments, four partial jaws, fourteen isolated teeth, sixteen vertebrae, sixteen ribs, twenty bones of the hands and feet, two bones of the wrist, three collar bones, two lower arm bones (radiuses), a thigh bone (femur), two knee caps, and other fragments from a minimum of six individuals. The people were between 3 and 18 years of age when they died. The skull and jaw fragments are too incomplete for detailed diagnosis, but the jaws clearly represent people whose faces were less massive and in some respects more modern-looking than those of
heidelbergensis
. The excavators have assigned them to a new species,
Homo antecessor,
from the Latin word for “pioneer” or “explorer.” The relationship of
antecessor
to other human species is debatable, but it seems an unlikely ancestor for
heidelbergensis,
and it may have been an offshoot of
ergaster
that disappeared after a failed attempt to colonize southern Europe. Its doom may have been sealed by an inability to cope with one of the harsh glacial episodes that gripped Europe between 800,000 and 600,000 years ago.
The TD6 people made artifacts on pebbles and cobbles of flint, quartzite, sandstone, quartz, and limestone, all of which they found within a few kilometers of the cave. Their tools were mainly small 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 138
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flakes, some of which they modified by striking tiny flakes or chips from along one or more edges. Archeologists call such modification
“retouch,” and ancient people did it to alter the shape of an edge, to give it greater stability, or to resharpen it after it had been dulled by use. In addition to flakes, TD6 has provided some hammerstones and a few cores from which the flakes were struck. Hand axes are totally absent, although they are commonplace in like-aged sites in Africa and southwestern Asia, and they occur in a higher-lying Gran Dolina layer that formed after 500,000 years ago. Their lack may mean that like
Homo
erectus
in eastern Asia, the ancestors of the TD6 people lost the hand axe habit on their trek from Africa. Alternatively, it is just possible that a hand axe will turn up when the small artifact sample is increased. So far, the excavators have exposed only 7 square meters (76 square feet) of TD6, and to enlarge this area, they must first remove a great thickness of overlying deposit. At their current pace, they estimate that they will reach TD6 again only in 2008.
TD6 would be exciting if all it had provided were human remains and artifacts, but it has also produced 1056 fragmentary animal bones that the people often cut, chopped, or scraped to obtain flesh and marrow. The bones come mainly from pigs, deer, horses, and bison, but there are also some from carnivores and from rhinoceros and elephant.
Compared to the larger species, the smallest ones are represented by a wider range of skeletal parts, suggesting that smaller carcasses more often reached the site intact. A similar contrast in skeletal parts between smaller and larger species characterizes prehistoric campsites of all ages, and it was thus predictable.
The surprise at TD6 is that the human remains resemble those of the smaller animal species not only in the wide range of skeletal parts 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 139
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represented, but also in the abundance and positioning of damage marks from stone tools. Twenty-five percent of the human bones show one or more forms of humanly caused damage. This includes chop and cut marks where large muscles were severed or stripped away; roughened surfaces with parallel groves or a fibrous texture that reflects
“peeling,” when a bone was partially broken by a blow and then bent across the break to separate the pieces; and percussion marks made when a bone was splintered for marrow extraction. Summing up, Atapuerca team leader and paleoanthropologist Juan-Luis Arsuaga says, “There is no doubt that the bodies were accumulated by other humans that ate them and left the human remains, along with the faunal remains and even the implements they used.”
The extent and positioning of damage marks suggest that the TD6 people butchered other people for food and not for ritualistic purposes, and it is tempting to draw a parallel with the situation on Easter Island when Europeans first arrived in the eighteenth century A.D. The Easter Islanders had severely degraded their environment, and their once-thriving population had shrunk by eighty percent. In desperation, the survivors had adopted a wide range of bizarre behaviors, including dietary cannibalism. In the short run, this helped some to carry on, but in the long term, it could only have hastened the slide towards population extinction. If cannibalism at TD6 reflects similar nutritional stress, it could explain why
antecessor
was ultimately unsuccessful.
The Neanderthals also seem to have practiced cannibalism, but only on occasion, and if the custom led to extinction, it affected only local populations. Still, as far as we know, the great apes do not turn to cannibalism when food is short, and the records from TD6, the Neanderthals, Easter Island, and late prehistoric sites in Europe and the 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 140
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American Southwest suggest that dietary cannibalism may be a specialized human tendency that
antecessor, neanderthalensis,
and
sapiens
inherited from their last shared ancestor.
Unlike TD6, the Italian site of Ceprano has provided only a single human fossil and no artifacts, but the fossil is important for its proposed age and for its form. It comprises most of a human skullcap that was shattered when a bulldozer struck it during highway construction in 1994. Potassium/argon analysis of volcanic layers at possibly younger and older localities nearby suggest that the skullcap is 900,000 to 800,000 years old. As reconstructed (Figure 5.3), it shares flat, receding
relatively small
forehead
braincase with thick
side walls
massive,
shelf-like
browridge
rear of skull
sharply
Ceprano
angulated
0
5 cm
0
2 in
FIGURE 5.3
The human skullcap from Ceprano, Italy (drawn by Kathryn Cruz-Uribe from a photograph).
(Copyright Kathryn Cruz-Uribe.)
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many features with skullcaps of
Homo erectus
, including a massive, shelf-like browridge, extremely thick skull walls, a sharply angled rear when viewed from the side, and a small internal volume (estimated at 1057 cc). If the Ceprano skull had been found in Java, it might have been assigned to
erectus,
and if its dating is correct, the anatomical contrast with
antecessor
implies a second, early, failed attempt to colonize Europe.
* * *
antecessor
or other earlier Europeans apparently could not reach. The reason was probably that late Acheulean Europeans benefited from technological advances that occurred somewhat before 500,000 years ago in the African source land. The reader will recall that the Acheulean (hand axe) Tradition began in Africa more than 1.6 million years ago and that it persisted in Africa, Europe, and the west Asian bridge between them until about 250,000
years ago.
Most African Acheulean sites are only weakly dated, but we have previously suggested that they may be divided between two stages—an earlier one before 600,000 years ago when the hand axes tended to be relatively thick, weakly trimmed, and asymmetric, and a later one after 600,000 years ago when they were commonly much thinner, more extensively trimmed, and more symmetric, both in plan form and in 05 Humanity Branches Out.r.qxd 1/29/02 5:05 PM Page 142
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ovate hand axe
cordate (”heart-shaped”) hand axe
subcordate hand axe
ovate hand axe
0
5 cm
0
2 in
FIGURE 5.4
