Denver, Colo. -- Dinosaurs and elephants may have had similar patterns
of decline in their long slide to extinction, according to a Penn State
paleontologist.
"If we look at the last five million years before extinction for both
dinosaurs and proboscideans, we find a surprisingly similar pattern of extinction,"
says Dr. Roger J. Cuffey, professor of geosciences.
The Proboscideans -- mammoths, mastodons, stegodons and elephants -- are
not quite extinct, but with only two species left, they are far reduced
from their heyday. The African and Indian elephants are the remnant of what,
at its height during the late Miocene, was a group of some 30 types of animals
roaming the Earth.
"Interestingly, at their height, dinosaurs also have a diversity of
about 30 species," Cuffey says.
Cuffey and Joey H. Eichelberger, a Penn State undergraduate, compared the
diversity of dinosaurs and proboscideans over the last 5 million years of
their existence in a poster presentation today (Oct. 30) at the annual meeting
of the Geological Society of America in Denver.
"Most people believe that we understand the extinction of the dinosaurs
now that we have proof of a large meteor event at the time of their final
demise," says Cuffey. "The KT meteor was only the final death
blow for the dinosaurs, they had been declining in diversity and number
for at least 5 million years."
For the proboscideans, the final death blow will probably be by the hand
of humans, but these elephant-like animals also suffered a gradual decline
in species number over the past 5 million years and only now approach extinction.
Although dinosaurs and proboscideans ruled at different times, placing both
decline curves on the same graph show that in their individual 5 million
year periods, these giant beasts shared a very similar pattern of decline.
"No one has ever put both graphs on the same chart before," says
Cuffey. "Because the patte
'"/>
Contact: A'ndrea Elyse Messer
aem1@psuvm.psu.edu
814-865-9481
Penn State
28-Oct-1996