Pleistocene Epoch

1.8 million to 12,000 years ago


By 500,000 years ago, hominids existed which some classify as ancestral to the modern species of humans.

ARCHAIC Homo sapiens/ Homo heidelbergensis
DATES: 500 thousand years ago to 200 thousand years ago
The earliest specimens classified as archaic Homo sapiens or Homo heidelbergensis have features of both H. erectus and H. sapiens sapiens with robust skeletons and teeth. Some specimens have brow ridges, receding foreheads, and receding chins. Some specimens already display some neanderthal facial characteristics (morphology of the eye sockets, cheekbones, and nasal bones) suggesting that neanderthals may have diverged from other lineages quite early. There is an advanced expansion of the cranial vault and the average cranial capacity was 1200 cc (Brauer, 1993; Howell, 1952; Trinkaus, 1997; Stringer, 1988; Stringer 1993; Arsuaga, 1997).
One significant change that occurred between the archaic and modern humans was a shortening of the sphenoid bone in the braincase. Externally, this change resulted in jaws, which did not protrude to the same degree. Internally, the change could have had a much more profound effect: it would have affected the dimensions of the oropharynx and the variety of sounds that humans could have made in speech. (Chimps and gorillas are capable of large vocabularies when using sign language and their use of signs suggests a degree of complex thought which they were previously thought to be incapable of. Apes do not speak because they do not have the anatomy for it. Thus changes in the vocal tract could have had a much larger impact on language than increases in brain size.) (Hublin, 1996; Rightmire, 1997; Rightmire, 1976; Holden, 1998).

THE PIT OF BONES: In Spain, the largest collection of Middle Pleistocene bones (1,600 bones from 32-50 individuals) was found dating at 300,000 years ago. Humans had been in Spain long before that: fossils of early Homo are known from 800,000 years ago and one site which has tools may be 1.2 million years old. As sea level rose and fell in the Pleistocene, there were times when the water levels separating Morocco and Spain were only half the current level so this migration would not have been difficult. Some feel that the primitive characteristics of these skeletons (such as a brow ridge and multiple roots for the premolars) warrant their classification as Homo antecessor, distinct from Homo heidelbergensis. If H. antecessor is distinct from H. heidelbergensis, it cannot yet be concluded whether H. heidelbergensis evolved from H. antecessor or from African Homo, (which bear similarities to H. heidelbergensis) which arrived at central Europe through the Middle East (Balter, 2001; Carbonell; 1995; Bermudez, 1997; Bahn, 1996).