Walking on four limbs allowed the dinosaurs to support more weight and grow bigger - often their best defence against predators, especially for herbivores like the diplodocus or the brontosaurus.And a bit later:
The fossil reveals a dinosaur with strong back legs and two stumpy front arms that are understood to have gradually grown with evolution.
The seven-metre long vegetarian lived around 200 million years ago.
Fellow paleobiologist Dr Matthew Bonnan said that although earlier discoveries showed some form of development from two to four legs, this latest find marked a clearer mid-point between the two bodies than ever seen before.
Enlarge Exciting: Dr Adam Yates, who led the research team, arranges the bones of the new dinosaur at a press conference in Johannesburg yesterday
Exciting: Dr Adam Yates, who led the research team, arranges the bones of the new dinosaur at a press conference in Johannesburg yesterday
He said: 'What Aardonyx shows us is that walking quadrupedally and bearing weight on the inside of the foot is a trend that started very early in these dinosaurs, much earlier than previously hypothesised.
'The bones of the forearm are shaped so that the forearm and hand could bear weight and that Aardonyx could drop onto all-fours as well as walk bipedally.'
Another piece of the puzzle. Neat!
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