Strategy moving predatory dinosaurs depended on their size — the representatives of the
small and medium-sized species evolved in the direction of maximum running speed in
while a larger bet on the efficiency of movement. To such conclusions of paleontologists from the United States and Canada in an article published in the journal Plos One. The opening will allow you to learn more about the evolution of carnivorous dinosaurs and to understand how they occupy a dominant position in Mesozoic ecosystems.
Throughout the greater part of the Mesozoic, the main predators of
terrestrial ecosystems remained saurischian dinosaurs, the theropods (Theropoda). The most famous
representatives of this group — the t-Rex and VelociRaptor and modern birds. Naticia
the theropods were very diverse: among them met as giants weighing more than
nine tons, and the medium and small sizes.
One of the features that contributed to the evolutionary success of prey
the theropod is considered to be characteristic of them, the ability to quickly and effectively navigate
on two legs. To confirm this idea, paleontologists carefully examine
the structure of the limbs in the theropod model and features of their movement.
Your approach to the problem of locomotion of predatory dinosaurs
presented a team of American and canadian researchers, led by Alexander
Dececco (T. Alexander Dececchi) College mount Marty, South Dakota. They suggested
what features of movement in different species of the theropod depended on their size. For
small and medium types were equally important as high speed and
efficiency of movement, because they had not only to hunt but also
themselves to escape from larger predators. At the same time, the theropods weighing more than
tons can focus solely on running efficiency.
During test this hypothesis, the researchers collected data on
the length of the body and of the limbs proportions of 93 individuals representing 71 genus carnivorous theropod
and early birds. The analysis included samples that have preserved at least one
the hindlimb. On the basis of information about the anatomy of the theropod, the authors calculated the maximum
movement speed and energy cost during a hunt.
Simulations showed that a predatory theropod, weighing more than a ton,
for example tyrannosaurs, increasing the length of the hind limbs did not lead to
the growth of the maximum speed. This is probably due to the fact that most of the
time these dinosaurs were moving at a relatively low speed capping
with this large distance. This is consistent with data on modern predators: for example,
the African wild dog (Lycaon pictus) while hunting on the move
a maximum speed of only eight percent of the time. This approach allows the most
efficient use of resources in conditions when the capture and killing of large
the production require large expenditures of energy.