Biology Reference
In-Depth Information
5 million and 7 million years ago, and scientists believe they were con-
fined to that continent until around 2 million years ago. When some of
them eventually left Africa, they appear to have spread to certain parts
of the world rather quickly, because their bones and tools have been
discovered from around 1.8 million years ago in Eurasia and Indonesia
and from 1.7 million years ago in China. (Europe seems to have been
colonized more recently.) The earliest fossils that were geographically
closest to Africa were unearthed in the Caucasus region of Eurasia
beneath a medieval castle in Dmanisi, in the Republic of Georgia. 18
As detailed below, these fossils (accepted here as a Eurasian variant of
Homo erectus ) reveal a perplexing combination of features that, gener-
ally speaking, were transitional between those of australopithecines
and early Homo.
By the time these hominins were living at Dmanisi, another Homo
erectus population had settled on the island of Java, in Indonesia. Appar-
ently, these hominins were very successful, because their descendants
are believed to have survived until quite recently on Java. 19 Like their
African relatives, the hominins who lived in Java are thought to have had
modern-humanlike limb proportions, which are associated with upright
posture and habitual bipedalism. They are known especially for their
long, low cranial vaults, which were comparatively thick. Recall, also,
that the Asian forms of Homo erectus have been of particular interest in the
discussions about whether or not Homo floresiensis was an insular dwarf.
Anatomically modern Homo sapiens appeared around 200,000 years
ago in Africa, and more recent representatives have been recovered from
all continents except Antarctica. 20 These specimens were big-brained
and looked essentially like us. They had rounded skulls with vertical
foreheads and faces and small brow ridges. Their faces and teeth were
small compared with those of their predecessors, and they had true
chins. Homo sapiens was also built more lightly below the neck.
As you know, Homo floresiensis remains were recovered on Flores from
strata that dated between 95,000 and 17,000 years ago, and stone tools
from the island go back to before 1 million years ago. Fortunately, the
Search WWH ::




Custom Search