National Geographic Explorer-in-Residence Paul Sereno
excavates an Eocarcharia dinops
jaw at the site of the dinosaur's discovery in the Sahara desert.
The newly revealed species give insights into southern-dwelling dinosaurs that rose to the top of the food chain during the Cretaceous period
, 65 to 144 million years ago.
"What we've found are primitive members of the two groups of megacarnivorous dinosaurs that ruled the southern continents for 50 million years," co-author Stephen Brusatte said.
The two new dinosaurs, along with an even bigger predator, the fish-eating, sail-backed Suchomimus
, represent a trio of meat-eating lineages that became dominant in Africa and possibly other southern landmasses, Sereno said.
(The National Geographic Society owns National Geographic News.)
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Photograph ) Mike Hettwer/courtesy of Project Exploration