The remains, most of which are still buried deep in the Sterkfontein caves
west of Johannesburg, are more complete than those of Lucy, the partial skeleton
of Australopithecus afarensis found in the Hadar region of Ethiopia in
1974. Unlike those of Lucy, however, the new remains include an intact
skull—and well-preserved leg and foot bones.

The bones have been dated to between 3.22 and 3.58 million years ago. If
these dates are confirmed, the new find would be the earliest australopithecine
ever found in southern Africa.

The find was announced last week by Ronald Clarke of the University of the
Witswatersrand in the South African Journal of Science (vol 94, p 460).
Because most of the bones are still encased in rock, it is too early to identify
the species. But Clarke predicts that the skeleton will provide a wealth of
information about the anatomy, behaviour and evolution of our early
ancestors.

“These bones are in virtually the correct anatomical alignment,” says Phillip
Tobias, a retired colleague of Clarke’s. “It’s now going to be possible to see
what joins onto what, what kind of teeth go with what kind of hands and what
kind of feet. We’ll be able to get a holistic picture of the anatomy of an early
˛ąłÜ˛őłŮ°ů˛ą±ô´Ç±čľ±łŮłó±đł¦ľ±˛Ô±đ.”

Tobias thinks the skeleton is the most important fossil discovery in Africa
since the Taung child found on the edge of the Kalahari Desert in northwest
South Africa in 1924. This skull of an australopithecine infant was the first
significant hominid find on the continent.

Clarke and Tobias have already drawn controversial conclusions from a portion
of the latest discovery. Four of its foot bones, which Clarke found while
rummaging in a box of fossils in 1994, led the two scientists to declare that
“Little Foot”, as the remains were whimsically named, had been capable of
walking on two feet, but also of climbing in trees. They claimed the talus, or
heel bone, was adapted to take the strain of a bipedal gait, but that the big
toe retained its ape-like ability to grasp (New ĐÓ°ÉÔ­´´, Science, 5 August 1995, p 14).

It was Clarke’s discovery two years later of more foot bones as well as the
left and right shinbones—all in rock fragments left after blasting by
miners in the 1930s and stored in the university’s strong room—that
inspired him to do the detective work that led him to the rest of the
skeleton.

In June 1997, Clarke asked two assistants to look for a match for the
sheared-off right shinbone in the large cavern from which the rock fragments had
come. Using hand-held lamps, they found the bone in two days. In the months of
digging that followed, they uncovered the rest of the hominid’s lower limbs, an
arm and, in September 1998, the skull, with the jaw not only intact, but also
with all the teeth in place.

“All of us are very thrilled that such a specimen exists,” says Don Johanson
of the Institute of Human Origins in Tempe, Arizona, who discovered Lucy. “It’s
going to be interesting to see what the upper and lower limb proportions are.
There are all sorts of things like that that we don’t know a lot about because
most fossil remains are not associated at all with one another.”

But Johanson says that the fossil’s significance will depend, in part, on its
age. Normal radioisotope dating techniques can’t be used on the Sterkfontein
remains. Instead, Clarke has had to rely on magnetic signatures in surrounding
limestone deposits and on the type of animal fossils found nearby. Some
scientists suggest the skeleton could be a million years younger than he claims.

SOUTH AFRICA, already facing the world’s worst human tuberculosis
epidemic, is confronting a new TB threat. Mycobacterium bovis, which
causes bovine TB, is sweeping through the Cape buffalo of the famed Kruger
National Park.

Nearly half of Kruger’s buffalo herds are affected. In the south of the
2-million-hectare park, few herds remain free of infection, and in some herds 85
per cent of the animals carry M. bovis. “It’s quite a problem,” says
Dewald Keet, the park’s chief veterinary surgeon.

Keet is a member of a group formed to work out how to contain the disease.
One concern is that bovine TB could spread into cattle along the park’s western
boundary. Local people drink unpasteurised milk and so are at risk of catching
M. bovis—which causes symptoms similar to human TB.

The group also wants to prevent TB spreading to other species. Worryingly, it
has already been found in three lions, two cheetahs and a troop of baboons. The
big cats were probably infected by eating diseased buffalo. And the same may be
true for the baboons: until the park’s pathologists began taking extra
precautions to keep the animals out of their laboratories, the baboons had the
unsavoury habit of scavenging from autopsy tables.

Six kudu have also been struck down by M. bovis. However, Nick Kriek
of the University of Pretoria, who is studying the outbreak, has found the
bacteria carried by the kudu are a different strain from those infecting the
other animals—indicating another, so far unknown, source of infection.

Keet suspects that the TB may have been present at low levels in the Kruger
buffalo since the 1960s, when cattle on a farm at the park’s southern boundary
were struck by such a severe outbreak that the entire herd had to be
slaughtered.

The first buffalo with TB in the Kruger park was identified in 1990. Since
then, scientists have surveyed animals slaughtered in the annual cull that is
conducted to limit the buffalo population to 28 000. They were shocked by the
high rate of infection, which is still rising.

In the past few weeks, Keet and his colleagues have dropped one radical plan
to halt the march of M. bovis. They proposed to kill some 10 000
buffalo in the south of the park, beginning in a 20-kilometre-wide belt south of
the Olifants River. Buffalo in the corridor would have been shot, and the zone
would gradually have been moved southwards, eradicating the infected buffalo,
and allowing repopulation by TB-free buffalo from the north. But the plan was
abandoned when surveys revealed that buffalo north of the Olifants River were
also infected.

Keet says that the group’s efforts will now focus on containing the disease
within the park. One positive sign is that the baboon outbreak appears to be
over. The infected troop lived in an old irrigation pumping station. Since the
pump house was sealed off last year, forcing the baboons to find less cramped
sleeping quarters, transmission of the bacterium seems to have halted.

THE first field trials of an elephant Pill have been suspended. The
trials, taking place in South Africa’s Kruger National Park, have thrown the
normally orderly elephant society there into turmoil.

Last October, a team of scientists from the Institute for Zoo Biology and
Wildlife Research in Berlin placed slow-release oestrogen implants, modelled on
human contraceptives, inside 10 elephant cows resident in the park.
Conservationists wanted to test birth control as a possible alternative to its
controversial culling programme in the overcrowded park. Until culling was
suspended last year, up to 600 elephants were killed annually. But the oestrogen
overload made the cows appear to be on heat permanently, which in turn
encouraged the constant unwanted attention of elephant bulls.

“They were in this state of continual false oestrus, and the bulls would not
leave them alone,” says Ian Whyte, the park’s elephant specialist. “When we
tracked them from the air, we would find a cow on her own surrounded by up to
eight bulls. That sort of thing, we feel, is not the way we want to treat the
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There was another consequence. The scientists had selected new mothers for
the trials because they were less likely to be pregnant. But the excited bulls
separated some cows from their calves.

Thomas Hildebrand, one of the researchers, concedes that the team had
“suspected” there would be problems with the use of oestrogen-only implants. But
he says he hopes the institute will be allowed to continue its work, using
combinations of hormones. Authorities at Kruger, however, warn that while the
park has not ruled out future trials, any hormone combinations would have to be
rigorously tested beforehand.

Jay Kirkpatrick, an expert in wildlife contraception at Zoo-Montana, a
zoological institute in Billings, Montana, claims that the hazards of giving
hormonal, implanted contraceptives to animals are well documented. He says that
ZooMontana abandoned hormonal birth control for wildlife in the 1970s “because
of its impracticality [and] because of the changes in behaviour” that it
produced.

Hormonal birth control is expensive and time-consuming, Kirkpatrick adds,
because the animals must be recaptured every six months for the implants to be
replaced. It has also been shown to cause tumours in zoo animals.

Meanwhile, scientists from ZooMontana and the University of Pretoria have
been working on a separate immuno-contraception programme in the Kruger National
Park. Last October they vaccinated 21 cow elephants with protein taken from the
layer of cells surrounding the ova of pigs. This stimulates the production of
antibodies that block sperm from penetrating the elephants’ own ova. The
elephants are to be given booster injections in June.