Evolution And History

(Marvins-Underground-K-12) #1
Miocene Apes 137

that humans originated entirely in Africa. European scien-
tists in the early 20th century therefore concentrated on the
various species of European ape—all members of the genus
Dryopithecus (pronounced “dry-o-pith-ee-kus”). They be-
lieved that humans evolved where “civilization” developed
and that these apes could be the missing link to humans.
As we will see in the next chapter, it took many years
for the first bipedal fossils discovered in South Africa in the
1920s to be accepted by the scientific community as key evi-
dence of the human line. Instead, human origins were imag-
ined to involve a close link between those who invented the
first tools and those responsible for Western civilization.
During the 1960s, it appeared as though this Miocene
human ancestor lived in the Siwaliks, the foothills of the ma-
jestic Himalayan Mountains along the northern borders of
India and Pakistan, near the ruins of the later Indus Valley

Africa to Eurasia, but that the environmental conditions
made it less likely that any of the African remains would
fossilize. Tropical forests inhabited by chimps and goril-
las today constitute unfavorable conditions for the pres-
ervation of bones. As mentioned in Chapter 5, in order to
become a fossil, bones must be quickly incorporated into
the earth before any rotting or decomposition occurs. In
tropical forests, the heat, humidity, and general abundance
of life make this unlikely. The bones’ organic matrix is
consumed by other creatures before it can be fossilized.
Nevertheless, the scarcity of African fossil evidence
from this time period fits well with notions about human
origins that prevailed in the past. Two factors conspired
to take the focus away from Africa. First, investigators ini-
tially did not consider that humans were any more closely
related to the African apes than they were to the other intel-
ligent great ape—the Asian orangutan. Chimps, bonobos,
gorillas, and orangutans were thought to be more closely
related to one another than any of them were to humans.
The construction of evolutionary relationships still relied
upon visual similarities among species, much as it did in
the mid-1700s when Linnaeus developed the taxonomic
scheme that grouped humans with other primates. Chimps,
bonobos, gorillas, and orangutans all possess the same basic
body plan, adapted to hanging by their arms from branches
or knuckle-walking on the ground. Humans and their an-
cestors had an altogether different form of locomotion:
walking upright on two legs. On an anatomical basis, the
first Miocene ape to become bipedal could have come from
any part of the vast Old World range of the Miocene apes.
The second factor drawing attention away from African
origins was more subtle; it was not embedded in the bones
from the earth but in the subconscious minds of the scien-
tists: It was hard for these Eurocentric researchers to imagine


Figure 6.7 Reconstructed skeleton of Proconsul. Note
the apelike absence of a tail but monkeylike limb and body
proportions. Proconsul, however, was capable of greater
rotation of forelimbs than monkeys.


For many years paleoanthropologists considered the European wood
ape Dryopithecus to be an important ancestor to humans. Fossil
remains had been discovered in Europe as early as the 1850s.
Eurocentrism allowed researchers to emphasize the European fossil
record and to explain away the evidence from Africa.

© Dr. David Begun
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