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Giant ants once
By Susan Milius
It’s not a bird or a plane; it’s an ant the
size of a hummingbird.
A winged ant queen fossilized in
49.5-million-year-old Wyoming rock
ranks as the first body of a giant ant from
the Western Hemisphere, says paleoentomologist Bruce Archibald of Simon
Fraser University in Burnaby, Canada.
The new species, Titanomyrma lubei,
is related to fossil giant ants previously
found in Germany, bolstering the notion
that the climate of the time had hot blips
that allowed these warmth-loving giant
insects to spread from continent to
continent, Archibald and a U.S.–Canada
team propose online May 4 in the
Proceedings of the Royal Society B.
An ancient ant wing from Tennessee
had hinted that big ants lived in North
America during this time, says Torsten
Wappler of the University of Bonn in
Germany. “But complete preserved spec-
imens were not known until Bruce came
up with this beautiful preserved fossil.”
The new fossil caught Archibald’s eye
as he and coauthor Kirk Johnson poked
around storage drawers at the Denver
Museum of Nature & Science, where
Johnson works. The spookiest thing
about the Wyoming ant may be that even
at 5. 1 centimeters long, she is not the
largest ant ever found. A German fossil
is slightly longer, as are queens of a liv-
ing African driver ant, Dorylus wilverthi.
At 5. 1 centimeters long, a 49.5-million-
year-old fossil ant queen from Wyoming
is the size of a rufous hummingbird.
opportunity fits the interpretation of
other fossils from the far north, says
paleoclimatologist Appy Sluijs of Utrecht
University in the Netherlands. Findings in
northern regions of preserved hippo predecessors, tropical plankton and pollen
from tropical palms support the idea.
Marine animals moved upriver early
Fossil worm burrows suggest rapid colonization of freshwater
By Alexandra Witze
Earth’s early animals moved upstream
not long after conquering the seas, newly
discovered fossils show.
© BRUCE ARCHIBALD
Rocks in eastern California preserve
traces of tiny worms that squiggled
through river mud some 530 million
years ago. That’s roughly 80 million
years earlier than other freshwater animal fossils, paleontologists report online
May 4 in Geology, and not long after the
first appearance of diverse animal forms
in marine environments.
Changing salinity can make it tough to
evolve from living in the ocean to living in
rivers and lakes, says Mary Droser, a pale-
ontologist at the University of Califor-
nia, Riverside. The new work shows that
“clearly animals had crossed that physio-
logical barrier very early on,” says Droser,
who made the find with Martin Kennedy
of the University of Adelaide in Australia.
June 4, 2011 | SCIENCE NEWS | 9