150 CHAPTER 7 | The First Bipeds
the scientific community was not ready to accept the
notion of a small-brained African ancestor to humans.
Dart’s original paper describing the Taung child was
published in the February 1925 edition of the presti-
gious journal Nature. The next month’s issue was filled
with venomous critiques rejecting Dart’s proposal that
this specimen represented an ancestor to humans. Criti-
cisms of Dart ranged from biased to fussy to sound.
Some scholars chastised Dart for incorrectly combin-
ing Latin and Greek in the genus and species name he
coined. Valid critics questioned the wisdom of making
inferences made about the appearance of an adult of the
species based only on the fossilized remains of a young
individual.
However, ethnocentric bias was the biggest obstacle
to Dart’s proposed human ancestor. Paleoanthropologists
of the early 20th century expected that the ancestor
to humans already had a large brain. Moreover, most
European scientists expected to find evidence of this large-
brained ancestor in Europe or, barring that, Asia.
In fact, many scientists of the 1920s even believed that
the ancestor to humans had already been found in the Pilt-
down gravels of Sussex, England, in 1910. The Piltdown
specimens consisted of a humanlike skull and an apelike jaw
that seemed to fit together, though the crucial joints con-
necting the two were missing. They were discovered along
with the bones of some other animal species known to be ex-
tinct. Charles Dawson—the British amateur archaeologist,2009, Ardipithecus was generally considered a side branch
on the human evolutionary tree. Now, the international
team has proposed that Ardi may be a direct ancestor to
the later bipeds, including humans.
The famous Ardi specimen, at 120 centimeters tall
and a weight of about 50 kilograms, is comparable in size
to a female chimpanzee. The size and shape of this partial
skeleton’s brain and the enamel thickness of the specimen’s
teeth are similar to chimpanzees as well. Though possess-
ing a grasping big toe, Ardi’s locomotion, unlike that of
a chimp, has been reconstructed as bipedal when on the
ground.
The Ardipithecus finds, along with the Orrorin and
Toumai specimens described in the previous chapter,
have begun to provide evidence for the time period be-
fore the appearance of the ancient bipeds belonging to
the genus Australopithecus. The first representatives of
this group were discovered in the early 20th century, long
before the majority of scientists were comfortable with
the now-accepted notion that humans originated on the
African continent.
Australopithecus
Most of the early bipeds from the Pliocene are members
of the genus Australopithecus, a genus that includes
species from East, South, and Central Africa. The name
for this group of fossils was coined back in 1924 when
the first important fossil from Africa proposed to be a
human ancestor came to light. This unusual fossil, con-
sisting of a partial skull and natural brain cast of a young
individual, was brought to the attention of anatomist
Raymond Dart of the University of Witwatersrand in
Johannesburg, South Africa. The “Taung child,” named
for the limestone quarry in the South African town
of Taung (Tswana for “place of the lion”) in which it
was found, was unlike any creature Dart had seen be-
fore. Recognizing an intriguing mixture of ape and
human characteristics in this unusual fossil, Dart
proposed a new taxonomic category for his discovery—
Australopithecus africanus or “southern ape of Africa”—
suggesting that this specimen represented an extinct
form that was ancestral to humans.
Although the anatomy of the base of the skull
indicated that the Taung child was probably a biped,
The Taung child, discovered in South Africa in 1924, was the first
fossil specimen placed in the genus Australopithecus. Though
Raymond Dart correctly diagnosed the Taung child’s bipedal mode
of locomotion as well as its importance in human evolution, other
scientists rejected Dart’s claims that this small-brained biped with a
humanlike face was a direct ancestor to humans. In the early 20th
century, scientists expected the ancestors to humans to possess a
large brain and an apelike face and to originate from Europe or Asia
rather than Africa.© Pascal Goetgheluck/Photo Researchers, Inc.Australopithecus The genus including several species of early
bipeds from East, South, and Central Africa living between
about 1.1 and 4.3 million years ago, one of whom was directly
ancestral to humans.