Paleontologists announced on Thursday July 7 that they had discovered the remains of a new giant dinosaur in Argentina, remarkable for its enormous head and small arms.
Baptized
Meraxes gigas
- after the name of a dragon present in the Game of Thrones series - this carnivorous predator was discovered during excavations carried out over four years in the north of Argentine Patagonia.
The skull was found first, in 2012.
"We won the lottery, we discovered it on the first morning"
of excavations, explained to AFP Peter Makovicky of the University of Minnesota, in the United States .
The skull measured more than 1.20 meters, and the animal more than ten meters, for a weight of about four tons.
But its upper limbs were no longer than 60 centimeters
"that is half of the skull"
and the animal could not use them to
"reach its mouth"
, specifies 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 surviving.
According to Peter Makovicky, as the head grew in size, it became the dominant tool in their predatory arsenal, taking on the function the upper limbs had in smaller species.
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Juan Canale, co-author of the study and project manager at the Ernesto Bachmann Museum in Neuquen, southern Argentina, goes even further.
“I am convinced that these proportionally reduced arms had a function.
The skeleton shows significant muscle insertions and fully developed pectoral girdles, so the arms had strong muscles,”
he explained in a press release.
“They could use their arms for their reproductive behavior, such as holding the female during mating or supporting themselves to get up after a break or a fall”
.
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The Meraxes lived on Earth 90 to 100 million years ago, during the Cretaceous, when the region was wetter, more forested and much closer to the sea, Peter Makovicky points out.
They could live up to forty years old, an advanced age for dinosaurs.
They presumably hunted sauropods living at the same time, the remains of which have been discovered at the excavation site.
With his skull full of ridges, grooves, bumps and little horns, Meraxes
“certainly looked very imposing, he looked like a gargoyle
,” says Makovicky.
“These are the types of characteristics that in living animals are often subject to sexual selection”
, emphasizes the researcher, specifying that these species used their massive skull as a “billboard” to get noticed by potential partners.
