| Since 1990 scientists from the American Museum
of Natural History and the Mongolian Academy of Sciences have been collaborating
on an ongoing expedition
to Mongolia, one of the world's richest sites of excellently preserved
dinosaur fossils. In 1993 at a site called Ukhaa Tolgod ("brown hills"),
members of the expedition discovered one of the most important finds that
Mongolia has yielded -- an egg containing the fossilized embryo of a theropod
dinosaur, thought to be 70 to 80 million years old.
Dinosaur eggs were found in the Gobi Desert by the Museum's Central Asiatic
Expedition of the 1920s, but none of them contained embryos. This is the first
such complete and informative example to be discovered there, as well as the
first embryo of a meat-eating dinosaur to be found anywhere in the world.
Studying the fossilized embryo, scientists identified it as an unhatched
oviraptorid, a dinosaur whose long neck and long hind legs resembled those of
an ostrich, while its skull looked like that of a parrot.
Mysteriously, in the same weathered nest in which the oviraptorid was
discovered, the scientists also found what may be two tiny Velociraptor
skulls, from either embryos or neonates. It is not clear what
Velociraptor were doing in an oviraptorid nest. They may have been items
of prey for adult oviraptorids, or have themselves been preying on oviraptorid
eggs or hatchlings. Or an adult Velociraptor may have had a parasitic
relationship with the oviraptorids, laying its eggs in the oviraptorid nest,
much as cuckoo birds today put their eggs in the nests of other birds.
Like most scientific discoveries, the Dinosaur Embryo raises as many questions
as it answers. Yet it is only through such continual investigation and
questioning that we are able to learn more about our world, both in the ancient
past and in the present.
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