African elephant istwo species,researchers say

Genetic researchers may have
resolved a long-standing
dispute by proving there are
two species of African elephant.
Savannah and forest elephants
have been separated for at least
three million years, they say, and
are as distinct from each other as
Asian elephants are from the
extinct woolly mammoth.
The researchers also made what
they say are the first sequences
of nuclear DNA from the extinct
American mastodon.
The study is reported in the
journal Public Library of Science
Biology.
The debate over whether the
African elephant is one or two
species has been going on for
about a decade.
Weighing in at six or seven
tonnes, the much larger
elephants found on savannah are
about twice as heavy as forest-
dwellers.
This, along with other
differences in size and shape,
has led some researchers to
conclude there are two species -
the savannah (or bush) elephant,
Loxodonta africana, and the
forest species, Loxodonta
cyclotis.
The scientists - from the US, UK
and Germany - now say they
have proved the case.
"The divergence of the two
species took place around the
time of the divergence of the
Asian elephant and woolly
mammoths," said Michi Hofreiter,
a specialist in ancient DNA at the
UK's York University.
"The split between African
savannah and forest elephants is
almost as old as the split
between humans and
chimpanzees. This result amazed
us all."
Ancient and modern
The researchers compared
sequences of DNA from the
nuclei of African and Asian
elephants, and from woolly
mammoths and the American
mastodon.
All are members of the
Proboscidea order of mammals.
The mastodon became extinct
about 10,000 years ago - around
the same time that mammoths
disappeared from most of their
range.
Although mastodon
mitochondrial DNA has been
sequenced before, the
researchers say they were the
first to do the analysis on DNA
from the cell nucleus - in this
case, using material from a tooth.
"Experimentally, we had a major
challenge to extract DNA
sequences from two fossils -
mammoths and mastodons - and
line them up with DNA from
modern elephants over hundreds
of sections of the genome," said
Nadin Rohland of Harvard
Medical School.
The genetic "distance" between
the Asian elephant and the
woolly mammoth turned out to
be about the same as between
the two African elephant species
- which, the researchers say,
proves the case for two distinct
species in Africa now.
Fragmented world
The picture of elephant
conservation across Africa is a
mixed one.
In southern countries, the
animals are thriving, with
populations increasing so fast
that governments have had to
consider culls.
However, the picture is very
different in Central and West
Africa, where poaching, ivory
smuggling and the bushmeat
trade are fragmenting
populations.
If there are indeed two species,
the forest dwellers are the ones
most under pressure, as they
tend to be found in areas where
poaching and smuggling are rife.
Potentially, confirming the
separation could help direct
conservation efforts where they
are most needed, according to
Simon Stuart, chair of the
International Union for the
Conservation of Nature's Species
Survival Commission (SSC).
"We'd have to review the
evidence to see whether we
need to split the African elephant
into two entries on the Red List
of Threatened Species," he told
BBC News.
"Currently the species is listed as
Vulnerable but it's possible that if
there are two, one would come
out in a more serious category
and the other in a less serious
one.
"This could be helpful for
highlighting the Central African
issue."
However, he cautioned, other
research groups may well
challenge the conclusion of the
latest study, and the debate may
have some way to run.
African elephant is
two species,
researchers say
By Richard Black
Environment correspondent, BBC
News
Poaching is a major concern in
parts of Africa - especially of
forest elephants
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The species is listed
as Vulnerable but
it's possible that if
there are two, one
would come out in
a more serious
category”
Simon Stuart
IUCN
The researchers say they have
also done the first nuclear
genetic analysis of the American
mastodon