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model for assessing how Lucy walked.
“Whatever we’ve been saying about
afarensis based on Lucy was mostly
wrong,” Haile-Selassie says. “The skel-
etal framework to enable efficient
two-legged walking was established by
the time her species had evolved.”
Lucy’s legs were short because of her
small size, he adds. If Lucy had been as
large as Big Man, her legs would have
nearly equaled his in length, Haile-
Selassie estimates.
Although lacking a skull and teeth, Big
Man preserves most of the same skeletal
parts as Lucy, as well as a nearly complete shoulder blade and a substantial
part of the rib cage.
“This beautiful afarensis specimen
confirms the unique skeletal shape of
this species at a larger size than Lucy,
in what appears to be a male,” remarks
anthropologist Carol Ward of the University of Missouri in Columbia.
A long-standing debate over how well
Lucy’s kind walked and whether her spe-
cies spent much time in trees appears
unlikely to abate as a result of Big Man’s
discovery, though. “There’s nothing spe-
cial I can see on this new find that will
change anyone’s opin-
ion” on how the species
navigated the landscape,
comments Harvard Uni-
versity anthropologist
Daniel Lieberman.
Big man’s skeleton was discovered in a part of the
afar region of ethiopia called Woranso-mille, about
48 kilometers north of the spot where Lucy was found.
Back Story | fragmentary evidence
even partial skeletons of Australopithecus afarensis have been hard to come by,
with only two adult specimens coming to light since the species was named. but
paleoanthropologists have collected numerous fragmentary fossils of the species
that have added to what’s known of lucy’s kind.
LH 4
This adult lower jaw,
discovered in 1974
in laetoli, Tanzania,
is the “type speci
men” that paleo
anthropologists cited
to establish A. afarensis as a species.
aL 333
This fossil is part
of the “First Family”
collection, a set of
more than 200 teeth
and bones that come
from at least 13
individuals.
aL 129-1
unearthed in novem
ber 1973, a year
before lucy’s discov
ery, this fossilized
knee joint estab
lished A. afarensis
as an uprightwalking
hominid.
aL 200-1
Found in 1974 by
donald Johanson,
one of lucy’s dis
coverers, this upper
jaw shows that A.
afarensis had apelike
teeth.
Fossil hominid skeletons as complete
as Big Man “are few and far between,”
says anthropologist William Jungers of
Stony Brook University in New York. But
the new find mostly confirms what was
already known about Lucy, he asserts.
Lucy’s kind, including Big Man, were
decent tree climbers, even if they couldn’t
hang from branches or swing from limb to
limb as chimpanzees do, he says.
“Riddle me this,” asks Jungers in con-
sidering Haile-Selassie’s proposal for a
ground-dwelling A. afarensis. “Where
did they sleep? Did they wait for fruit to
fall to the ground? Where did they go to
escape predators?”
Groups of A . afarensis individuals must
have devised ground-based strategies to
ward off predators, Lovejoy responds.
Some big cats would have negotiated
trees better than Lucy’s kind, he notes.
Jungers also doubts Lovejoy and
Haile-Selassie’s assertion that a humanlike gait had evolved in A. afarensis. Big
Man includes only one nearly complete limb bone, from the lower left leg,
which makes it difficult to estimate how
long his legs were relative to his arms,
Jungers contends.
Haile-Selassie doubts additional
pieces of Big Man’s skeleton will turn up.
“If anything more was there, we would
have found it by now,” he says with a
resigned laugh. s
