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Masiakasaurus knofleri
(Sampson, 2001) |
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Name Means: |
"Vicious Lizard" |
Length: |
7 ft.(2 meters) |
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Pronounced: |
ma-Zii-uh-kuh-Sore-us |
Weight: |
3 ft.(1 meters) |
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When it lived: |
Late Cretaceous - 67 MYA |
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Abelisaurids |
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Where found: |
Madagascar, Africa |
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Masiakasaurus was a
very strange looking dinosaur from Madagascar..
It had a long neck and tail, walked on two feet,
and weighed about as much as a German shepherd, but is most unique
characteristics is its front teeth. They stuck almost straight out from the front
of its mouth. This dental feature has been found on some flying
reptiles, but this is the first time that it has been found on a
dinosaur.
The discovery was announced in January of 2001in the journal
Nature this week by a team of researchers led by paleontologist
Dr. Scott D. Sampson of the University of Utah. Additional authors on the
paper are Dr. Matthew T. Carrano and Dr. Catherine A. Forster, both
from the State University of New York at Stony Brook. The fossils
consist of a number of isolated bones from several individuals, most
recovered from a single site. Included in the collection are parts of
the jaws and about 40% of the remainder of the skeleton, with some
bones represented by multiple examples.
The uniqueness of the teeth was immediately apparent.
“When we dug up the first lower jaw
bone, we weren’t even sure it belonged to a dinosaur,” said Sampson.
"It was only after we compared it with the lower jaws of other
carnivorous dinosaurs that we became convinced as to the nature of the
owner. Certain features at the back of the jaw are unmistakably
theropod." Theropods are the group of meat-eating dinosaurs that
included Tyrannosaurs and Velociraptor. "The lower front teeth are nearly
horizontal, with the teeth angle increasing until the dinosaur’s
fourth tooth, after which the teeth are vertical. Although the back teeth of the dinosaur are similar to other
predatory dinosaurs, their horizontal, conical front teeth are
otherwise unknown among other (predatory) dinosaurs.” One
sharp-witted dinosaur enthusiast remarked that the dinosaur really
need a good orthodontist.
Masiakasaurus habits are a mystery. There are a few
species of living mammals with similar dental features and they may
provide some clues. These animals include various shrews and a group
of South American marsupials known as caenolestids. These mammals
also have
elongate, conical, forward-projecting teeth up front. In virtually all
cases, the front teeth are used for grasping and piercing rather than
tearing and slicing, and the prey generally consists of insects.
The jaws of Masiakasaurus suggest a similar
feeding strategy, with the front teeth used to capture and manipulate
animal prey, and the blade-like rear teeth then slicing and tearing
the victim into bite-sized chunks. As to the nature of the preferred
prey of this little dinosaurian carnivore, potential candidates
include insects, fish, lizards, snakes, and mammals.
The name of the new dinosaur is derived from masiaka, the
Malagasy word for “vicious” and sauros, which is Greek for
“lizard.” Knopfleri honors musician Mark Knopfler, lead
singer of Dire Straits. According to Scott Sampson, the band's music was a 'talisman'
for the research team: whenever they played it, they'd find another
fossil. Literally translated, it means "'Vicious lizard of Knopfler".
Madagascar is the fourth largest island in the world.
It is located more than 500 miles off the southeastern coast of Africa.
Today it is well known for being home to some of the world's most unusual animals,
the great majority of which are highly endemic (that
is, known only from Madagascar).
70 million years ago. It was inhabited by such weird critters as
a pug-nosed, land-dwelling, plant-eating crocodiles, flying raptors,
giant, thick-skulled carnivorous dinosaurs and two unique carnivorous
dinosaurs. The area then seems to have been cosmopolitan. In other words, the animals preserved in
the Late Cretaceous of Madagascar closely resemble those found on
other southern hemisphere continents. In addition, it appears
that the ancestors of modern Malagasy animals had not yet arrived by
the Late Cretaceous, suggesting that they reached Madagascar following
its isolation as an island.
Masiakasaurus is one of two thick-skulled carnivorous
dinosaurs found on Madagascar. Both it and its' larger cousin Majungatholus are members of an enigmatic group known
as abelisaurids, which have only been recovered from the Southern
Hemisphere. The fossils of Masiakasaurus share a number of
specialized characteristics with predatory dinosaurs found in
Argentina and India and indicate that small-bodied predatory dinosaurs
spread out across much of the Southern Hemisphere toward the end of
the Age of Dinosaurs.
Madagascar was once part of the southern supercontinent Gondwana,
which began to break up the heyday of dinosaurs around 140 million
years ago. Together with fossil evidence that the larger
abelisaurids
theropods also spread out over the Southern Hemisphere in the Late
Cretaceous, this most recent finding supports a recently proposed
theory that Gondwanan landmasses retained connections much longer than
previously thought.
"If so", Sampson said, "then dinosaurs and other land animals may have been
able to travel the vast distances between South America and
India-Madagascar because the two regions remained connected via
intervening land masses." |
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Edugraphics.Net | Feenixx Publishing |
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