[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Tyrannosaurs rex hunter/scavenger



With reference to the debate on scavenging in Tyrannosaurs rex:

The only major proponent of this therory in recent years has been J.
Horner.  His basic premisies are:

1)  All modern hunters use their forelimbs in capturing prey.

and

2)  Tyrannosaurus lacks speed adaptations.

Statement 1 is demonstrably incorrect:  although felids (cats and great
cats) do certainly use their forelimbs in prey acquisition, most other
predators, such as canids (dogs, wolves,etc.), hyeanas, secretary birds, and
such rely primarily on their jaws.  It should be noted here that several
groups of extinct large predatory birds (phorusrachids, diatrymid, and
perhaps a few more) almost certainly used only their beaks in killing, as
these groups were flightless and (unlike modern predatory birds) could not
swoop down on their prey.

Statement 2 is also incorrect.  Tyrannosaurs have proportionately elongate
hind limbs (in fact, Tyrannosaurus rex has the same limb element ratios as
many smaller dinosaurs, such as Dryosaurus, Dilophosaurus, and
Coelophysis).  Although tyrannosaurs may not have been capable of race horse
speed as some advocate, they certainly were faster than an equivalent sized
allosaurid or ceratosaurian.

Another aspect to this debate is: if Tyrannosaurus rex was not the top
predator of the latest Cretaceous western North American fauna, what was?
The sickle-clawed dromaeosaurids of this interval were all relatively small
(smaller than the earlier Deinonychus).  There are no other suitable top
predators.

A final note:  Although this debate centers on the species Tyrannosaurus
rex, there are other members of the Tyrannosauridae which approach the big
guy in size:  Tyrannosaurus (sometimes Tarbosaurus) bataar, large specimens
of Albertosaurus libratus, and large specimens of Daspletosaurus torosus.

Hope this information proves useful.