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Embargoed until 4 P.M., EST
NSF PR 98-16 - March 20, 1998
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New Sickle-Clawed Fossil from Madagascar Links Birds
and Dinosaurs
A new raven-sized fossil bird, showing clear evidence
of the close relationship between theropod dinosaurs
and birds, has been discovered on the island of Madagascar
by scientists working under a National Science Foundation
(NSF) grant. This discovery was announced by a team
of researchers -- led by paleontologist/anatomist
Catherine Forster of the State University of New York
(SUNY) at Stony Brook -- in this week's issue of the
journal Science.
"This discovery is a wonderful example of how the
fossil record provides the basic data for formulating,
testing, and revising ideas about life through time,"
says Chris Maples, director of NSF's geology and paleontology
program, which funded the research.
The fossil bird is 65 to 70 million years old and
dates from the Late Cretaceous period. It was discovered
in 1995 by an international team of paleontologists
led by researcher David Krause, also of SUNY-Stony
Brook. The scientists have named the new discovery
Rahona ostromi, meaning "Ostrom's menace from the
clouds." Scientists Scott Sampson (New York College
of Osteopathic Medicine) and Luis Chiappe (American
Museum of Natural History in New York) are also co-authors
of the Science paper.
The forearm bone of Rahona is long and shows evidence
of well-developed feathers, indicating it was a capable
flyer. But unlike most birds, Rahona also had a long,
bony tail and sported a large, sickle-like killing
claw at the end of a thick second toe on the hind
foot. This unique toe and claw is identical to the
one carried by a group of fast, predaceous theropod
dinosaurs called "maniraptorans." It is these maniraptoran
dinosaurs (a group that includes Velociraptor and
Deinonychus), that many, but not all, scientists believe
gave rise to birds. "This new fossil is one of the
strongest last nails in the coffin of those who doubt
that dinosaurs had anything to do with the origin
of birds," stated Forster.
Forster added, "Rahona was at the base of the bird
family tree, right next to Archaeopteryx. It had a
feathered wing and many bird features in its hips
and legs, including a perching foot. But it also kept
the big killing claw of its theropod ancestors." Paleontologists
have long suspected that theropods gave rise to birds,
and the presence of this "maniraptoran" toe and claw
on the Malagasy bird "clinches it for us. This discovery
lends a lot of weight to the idea that birds are a
side-branch of the theropod family tree," says Forster.
The discovery was made during one of a series of ongoing
paleontological expeditions in Madagascar, funded
by NSF. In addition to Rahona, the scientific team
discovered an array of well-preserved skeletal remains
of other fossil animals, including theropod and sauropod
dinosaurs, mammals, turtles, snakes, crocodiles and
other birds. Another expedition to Madagascar is planned
for this summer.
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