An artistic reconstruction of Meraxes gigas
A team of scientists in Argentina say they have discovered a new giant predatory dinosaur that had a huge head, but tiny arms because of its size.
Writing in the journal Current Biology, scientists say extensive remains of skeletons of an unknown species were excavated in northern Patagonia.
Meraxes gigas was about 11 m long, with a 4-foot skull, but his arms were only 2 feet long.
Scientists believe that small limbs gave carnivores survival benefits.
“I’m convinced those proportionately tiny arms had some kind of function. The skeleton shows large muscle insertions and fully developed pectoral fissures, so the arm had strong muscles,” said Juan Canale, lead author of the study.
“He may have used his arms for reproductive behavior, such as holding the female during mating or leaning up to get up after a pause or fall,” he added.
Its co-author Peter Makovicky said the dinosaur’s arms were “literally half the length of the skull and the animal could not have reached its mouth.”
Makovicky said he believed the massive heads of the species were the main predatory tool, assuming the functions the arms would have had in smaller species.
Peter Makovicky says the dinosaur’s arms were “literally half the length of the skull.”
Meraxes gigas, named after a fictional dragon from the Game of Thrones book series, belonged to the carcharodontosaurids, or sharks with shark teeth.
Four-ton reptiles are believed to have traversed the Earth about 90-100 million years ago.
Scientists say two other species, tyrannosaurids and abelisaurids, also developed small arms for similar reasons.