- A "lost world" of early dinosaurs roamed the
Antarctic long after they were supplanted in the rest of the world, the
recent discovery of fossilized bones suggests.
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- A team of dinosaur-hunters has found remains of a new
species which dates from only 70 million years ago, but which bears striking
similarities to dinosaurs thought to have died out everywhere else ten
of millions of years earlier.
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- Expedition leader Judd Case, dean of science and biology
professor at California's Saint Mary's College, told globeandmail.com from
Washington, D.C., that the radically changing day-night cycle of the far
south probably slowed the spread of flowering plants, which could in turn
have limited the evolution of the massive, plant-eating dinosaurs found
farther north.
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- "One of the surprising things is that animals with
these more primitive characteristics generally haven't survived as long
elsewhere as they have in Antarctica," Dr. Case said. "For whatever
reason, they were still hanging out on the Antarctic continent."
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- The creature, which has not yet been named, is thought
to have been a relatively small theropod, a carnivorous group of upright
dinosaurs that also includes the fearsome tyrannosaurus.
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- The research team found fragments of an upper jaw with
teeth, a number of loose teeth and most of the bones from the creature's
lower legs and feet. A curator of vertebrate paleontology with the group
said that the size and shape of the lower-leg and foot bones suggests the
animal was about two metres tall.
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- Dr. Case said that the size of the dinosaur was "very
unusual" and raised a host of new questions.
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- "Does that relate to the habitat it's in?,"
he asked. "I think for us that becomes one of the really interesting
questions. How does this particular dinosaur say something about living
in ... those higher latitudes and the day-night cycle?"
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- A veteran dinosaur-hunter, Dr. Case acknowledges that
luck played a major part in the discovery. The remains survived as well
as they did because the creature's body probably floated out from shore
and then settled to the bottom of the Weddell Sea, much shallower back
then.
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- The remains were found on a volcanic island lying off
the Antarctic Peninsula. The peninsula juts off the continent in the general
direction of South America. A cruelly inhospitable spot now, at the time
this creature would have lived it was much warmer and had a climate something
like the U.S. Pacific Northwest.
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- Also announced Thursday was the discovery of the remains
of a plant-eating dinosaur, found in the interior of the continent near
the Beardmore Glacier. This creature, which lived millions of years before
the carnivore, is thought to have been a very large but primitive sauropod.
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- Team leader William Hammer, a professor of geology at
Augustana College in Rock Island, Ill., returned to the site of an earlier
discovery with a team that included Philip Currie and Kevin Kruger, both
from Canada's Royal Tyrell Museum.
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- While waiting for workers to stabilize the spot by removing
a dangerous overhang, he and a mountain safety guide on the team were wandering
on an informal search for fossils. The guide marked a handful of spots
that seemed interesting, one of which Dr. Hammer realized was part of a
huge pelvis, "much, much bigger than the corresponding bones"
in his previous discovery.
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- "This site is so far removed geographically from
any site near its age, it's clearly a new dinosaur to Antarctica,"
Dr. Hammer said. ìWe have so few dinosaur specimens from the whole
continent, compared to any other place, that almost anything we find down
there is new to science."
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- Analysis of the metre-wide pelvis has led the team to
surmise that the creature -ñ which stood around two metres tall
and was up to nine metres long -ñ represents one of the earliest
examples of the dinosaur lineage that ultimately produced animals more
than 30 meters long.
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