The scientists say the creature provides the earliest evidence
for the origins of many skeletal characteristics seen in the
ornithischian group, including the backward-pointing pelvis.
A comparison has been done across a wide range of specimens and
this indicates that Late Triassic ornithischians were really quite
rare. The group then diversified in the subsequent early Jurassic,
filling empty herbivorous niches following mass extinctions of other
"We know ornithischians were a very successful and important
group of plant-eating dinosaurs that first appeared 220 million
years ago, in the late part of the Triassic Period," explained Dr
Richard Butler, a palaeontologist at the Natural History Museum,
"Eocursor is a very small and primitive dinosaur that
would have eaten plants with its leaf-shaped teeth and had an
unusually large, grasping hand. The lower leg bones are very long,
suggesting it would have been able to run fast on its hind legs to
escape from predators."
The name Eocursor comes from the Greek eos,
meaning "dawn" or "early", the Latin cursor meaning "runner"
and parvus meaning "little".
"The earliest dinosaurs we know are about 228 million years old,
so this one is only just a bit younger than that," commented Dr Paul
Barratt, a NHM researcher unconnected with the new study.
"The fossil record for early meat-eating dinosaurs is slightly
better; and for some of the other plant-eaters, we also have
not-too-bad a record. But for the ornithischians, we have almost
nothing; so in that sense, this is a major find," he concluded.
The assessment is reported in Proceedings of the Royal Society
B: Biological Sciences.
The research team included co-workers at the Iziko South African
Museum in Cape Town and the University of Cambridge, UK.