New fossils reveal a world full of crocodiles
New fossils unearthed in what is now the Sahara desert reveal a
once-swampy world
divided up among a half-dozen species of unusual and perhaps
intelligent crocodiles, researchers reported.
They have given some of the new species snappy names — BoarCroc,
RatCroc, DogCroc, DuckCroc and PancakeCroc — but say their findings help
build an understanding of how crocodilians were and remain such a
successful life form.
They lived during the Cretaceous period 145 million to 65 million
years ago, when the continents were closer together and the world warmer
and wetter than it is now.
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crocodile. Courtesy: Internet |
“We were surprised to find so many species from the same time in the
same place,” said paleontologist Hans Larsson of McGill University in
Montreal who worked on the study.
“Each of the crocs apparently had different diets, different
behaviors. It appears they had divided up the ecosystem, each species
taking advantage of it in its own way.”
Larsson and Paul Sereno of the University of Chicago, funded by
National Geographic, studied the jaws, teeth and what few bones they had
of the crocodiles. They also did CT scans, which are computer-enhanced
x-rays, to see inside the skulls.
Two of the species, DogCroc and DuckCroc, had brains that looked
different from those of modern crocodiles.
“They may have had slightly more sophisticated brain function than
living crocs because active hunting on land usually requires more brain
power than merely waiting for prey to show up,” Larsson said in a
statement.
RatCroc, a new species formally named Araripesuchus rattoides, was
found in Morocco and would have used its buck-toothed lower jaw to grub
for food.
PancakeCroc, known scientifically as Laganosuchus thaumastos, was 20
feet long with a big, flat head.
DuckCroc represents new fossils found in Niger from a previously
known species called Anatosuchus minor.
It would have eaten grubs and frogs with its broad snout.
The more ferocious BoarCroc was also 20 feet long but ran upright and
had a jaw built for ramming, with three pairs of knife-like teeth.
Some walked upright with their legs under the body like a land mammal
instead of sprawled out to the sides, bellies touching the ground.
“Their amphibious talents in the past may be the key to understanding
how they flourished in, and ultimately survived, the dinosaur era,”
Sereno wrote in a separate article for National Geographic.
Reuters
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