T.rex's Horny Ballerina Cousin

Galvasean

A new species of Alioramus (A.altai) has proven to be avery unusual member of the tyrannosaur family. It had eight horns on it's head, a first in carnivorous dinosaurs, and had a very light build (unlike the more bulky frames of most tyrannosaurs), complete with narrow skull and slim teeth (unlike other tyrannosaurs which had massivly built skulls and thicker teeth). The horns would have been useless for fighting, so instead were most likely ornamental, used to attract mates or intimidate rivals. The light build suggests that Alioramus altai was a swift hunter, the cheetah of it's day, whereas it's larger relative Tarbosaurus bataar most likely occupied an ecological niche of the top predator, similar to a modern lion.

The predator lived in the hot, lush floodplains of the late Cretaceous, near the end of the age of dinosaurs, roughly 65 million years ago.

The creature had two short horns above each eye and two jutting downward from its cheeks—all four are also seen in T. rex.

Strangely, the beast also had up to two-inch-long (five-centimeter-long) horns sticking out of each cheek, "which have never been seen in any carnivorous dinosaur before," Brusatte said.

Too short for combat, these horns likely served as sexual ornaments to attract females.

Smaller than T. rex, the newfound species also possessed an unusually airy skeleton; lacked a skull built for the strong jaws seen in its larger cousins; and had thinner, steak knife-like teeth

Full article here.


Top illustration by Jason Brougham. Skull illustration by Frank Ippolito

dlofnep

Best thread title, evar?

girl_friday

Interesting article!

Galvasean

A liitle bit more info on Alioramus for anyone who is interested.

It lived in Asia in the late Cretaceous at the same time as the larger tyrannosaur Tarbosaurus. At only 5 metres long (small for a tyrannosaur) many believed it to be a juvenille Tarbosaurus, until these were actually found and were suitably different to Alioramus, justifying it being classed as it's own genus.
(For more on the confusion that can arise when trying to tell the difference between new species and juvenilles click here.).

A. altai is the second species of Alioramus (which means 'different branch' referring to how it seems to have ventured on a different evolutionary route to most tyrannosaurs) to be named. The first was A. remotus which was first properly described in 1976.
Alioramus remotus also featured unusual head gear. It had a curious ridge along it's snout complete with six bumps which were probably covered with horn.
The presence of such horns would indicate (assuming that they were indeed used for sexual display) that Alioramus is not a juvenille of a larger tyrannosaur as it would be quite counter productive for an animal to lose it's sexual display structures when it reached sexual maturity. One could argue that only juvenilles would have horns in order to ward off would be predators, but this also begs the question as to why a most likely territorial animal such as a large tyrannosaur would grow out of having such potentially useful structures.

Headshot of Alioramus remotus:

Picture by Peter Schouten.

Weidii

Whoa, that's an amazing picture.

*abandons hope of becoming a palaeo-artist*