Fossils of megaraptors, a carnivorous dinosaur that inhabited
parts of South America during the Cretaceous period some 70
million years ago, were found in sizes up to 10 meters long,
according to the Journal of South American Earth Sciences.
"We were missing a piece," Marcelo Leppe, director of the
Chilean Antarctic Institute (INACH), told Reuters. "We knew
where there were large mammals, there would also be large
carnivores, but we hadn't found them yet."
The remains, recovered from Chile's far south Rio de las Chinas
Valley in the Magallanes Basin between 2016 and 2020, also
include some unusual remains of unenlagia, velociraptor-like
dinosaurs which likely lived covered in feathers.
The specimens, according to University of Chile researcher Jared
Amudeo, had some characteristics not present in Argentine or
Brazilian counterparts.
"It could be a new species, which is very likely, or belong to
another family of dinosaurs that are closely related," he said,
adding more conclusive evidence is needed.
The studies also shed more light on the conditions of the
meteorite impact on Mexico's Yucatan Peninsula that may have
triggered the dinosaurs' extinction some 65 million years ago.
INACH's Leppe pointed to a sharp drop in temperatures over
present-day Patagonia and waves of intense cold lasting up to
several thousand years, in contrast to the extremely warm
climate that prevailed for much of the Cretaceous period.
"The enormous variation we are seeing, the biological diversity,
was also responding to very powerful environmental stimuli,"
Leppe said.
"This world was already in crisis before (the meteorite) and
this is evidenced in the rocks of the Rio de las Chinas Valley,"
he said.
(Reporting by Marion Giraldo; Writing by Sarah Morland, Editing
by Alistair Bell)
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