Paleontologists announced Thursday that they have discovered the remains of a new giant dinosaur in Argentina, distinguished by its massive head and small arms.
Named Meraxes gigas – after a dragon in the Game of Thrones series – this carnivorous predator was discovered during four years of excavations in northern Argentine Patagonia. The skull was first found in 2012.
“We won the lottery, and we discovered it on the first morning” of the excavation, explained Peter Makovicki of the University of Minnesota in the US.
The skull measured more than 1.20 meters, and the animal more than ten meters, weighing about four tons. But its upper limbs were no longer than 60 centimeters “half the skull” and the animal could not use them “to reach its mouth,” according to the researcher.
The team of scientists, who published the results of their research in the scientific journal Current Biology, believe that the small size of the arms gave the animal a certain advantage in survival.
According to Makovicki, as the head grew in size, it became the dominant tool in its predatory arsenal, taking on the function of the upper limbs in smaller species.
Juan Canal, co-author of the study and project director at the Ernesto Bachmann Museum in Neuquén, southern Argentina, goes further.
I’m convinced that these relatively reduced guns do a job. He explained in a press release that the skeleton shows large muscle insertions and fully developed pectorals, so the muscles of the arms are strong.”
“They can use their arms in their reproductive behaviour, such as holding the female during mating or supporting themselves to get up after a break or fall.”
Makovicki notes that Mirax lived on Earth 90 to 100 million years ago, during the Cretaceous period, when the area was wetter, forested, and much closer to the sea.
They can live to the age of 40, which is an advanced age for dinosaurs. It is assumed that they hunted sauropods living at the same time, the remains of which were discovered at the excavation site.
With his skull full of bumps, grooves, bulges, and little horns, “Mirax definitely looked very imposing, it looked like a garter,” says Makovsky.
“These are the kinds of characteristics that in living animals often undergo sexual selection,” the researcher asserts, specifying that this species uses its massive skull as a “bulletin board” to attract attention from potential partners.