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The biggest flying monster in the world
The largest known creature ever to have flown, an extinct reptile with
an estimated wingspan of 51ft, has been discovered by fossil hunters in west
Texas.
The creature, which lived more than 60 million years ago, had twice
the wingspan of the biggest previously known pterodactyl, or winged reptile,
and nearly six times the wing-span of the condor, the largest bird now alive.
The estimated size of the creature is derived from calculations based on
the size of many fragmentary, and some complete bones found in excavations
during the past three years at Big Bend national park in Brewster County,
Texas.
Announcement of the discovery, in the present issue of
Science, is expected to rekindle an old debate among palaeontologists
over whether flying reptiles flapped their featherless, leathery wings or
merely climbed on to high perches and leapt into the air currents to soar like
gliders.
One scientist familiar with the discovery said that the mammoth
size of the newly found creature made improbable the theory that it was able to
rise into the air under wing-power alone. He noted, however, that the lack of a
reliable estimate of the reptile's weight virtually precluded any
calculation of its aerodynamic properties.
The fossils were found by Mr
Douglas Lawson, a graduate student at the University of California, who began
searching in the Big Bend area while a student at Texas University. His
continuing explorations and study of the fossils are being carried out under
the auspices of the university's vertebrate palaeontology laboratory.
Although the reptile clearly represents a new species, it has not yet been
given a formal scientific name. There are many known species of flying
reptiles. Scientists generally refer to all as pterosaurs, but the popular name
pterodactyl is also considered correct. All are extinct.
'What's
so extraordinary about this thing is its tremendous size', Dr Wann
Langston, director of the vertebrate palaeontology laboratory, said. 'There has never been anything like this before.'
In his report Mr
Lawson says he has discovered the partial skeletons of three of the large
pterosaurs, including the remains of four wings, a neck, the hind legs
(forelimbs with claws are frequently part of the wing structure), and jaws,
which were toothless.
Unlike most previously known pterosaurs, the Big Bend
creature was found in non-marine sediments, suggesting that its habitat was
away from oceans. Most pterosaurs are considered to have been fish eaters,
scooping up their prey while gliding over the waves.
The Big Bend fossils
were found in fresh-water sediments far from the oceans of that time. In his
report Mr Lawson writes that the reptile's unusually long neck suggests it
may have been a carrion-eater, feeding on dead dinosaurs, much as the condors
and other vultures of today consume dead animals. |