Miniature, insect-eating ancestor of dinosaurs unearthed in Madagascar
A small, insect-eating reptile that lived 237m years ago was a miniature ancestor of the giant dinosaurs that went on to dominate the Earth, according to scientists examining fossils in Madagascar.
The Kongonaphon kely measured about 40cm (16in) long and stood 10 cm (4in) tall at the hip, scientists said on Monday. It inhabited a floodplain region of what is now south-western Madagascar during the Triassic period about 237m years ago.
Kongonaphon was a long-legged predator that may have been bipedal. The shape of its small, conical and unserrated teeth and an examination of microwear on them suggests Kongonaphon, whose scientific name means “tiny bug slayer,” ate insects or other small invertebrates.
It was a member of a group called Ornithodira spanning the evolutionary lineage that led to dinosaurs and pterosaurs – large flying reptiles – part of a larger assemblage called archosaurs that also included the crocodilian lineage.
“Based on statistical analyses of body size, we argue that dinosaurs and pterosaurs evolved from a miniaturized ancestor,” said North Carolina Museum of Natural Sciences paleontologist Christian Kammerer, lead author of the research published in the Proceedings of the National Academy of Sciences.
“Evolution of gigantism from tiny ancestors is not uncommon in the fossil record,” added study co-author and paleontologist John Flynn of the American Museum of Natural History in New York.
Dinosaurs and pterosaurs first appeared roughly 230m years ago. The early dinosaur Herrerasaurus was about 6 metres (20ft) long. The early pterosaur Eudimorphodon was pigeonsized. Both groups eventually achieved gigantic proportions. The pterosaur Quetzalcoatlus had a wingspan of about 10.5 metres, akin to an F-16 fighter. The dinosaur Argentinosaurus reached about 35-metres long.
“In the context of this later gi
gantism, having an animal like Kongonaphon “that could fit into your hands seems almost paradoxical”, Kammerer added.
“However, it fits the broader pattern that we observe at this time. There was a sustained trend towards smaller adult body sizes in the early history of this lineage. This is based not only on Kongonaphon, but on a series of small-bodied reptiles near the common ancestry of the dinosaur and pterosaur lineages.”