100mn-yr-old ancestor of carnivorous insect fossil reveals evolution stasis
By ANIFriday, February 4, 2011
WASHINGTON - Researchers at the University of Illinois have found a 100 million-year-old fossil of the ancestor of a carnivorous, cricket-like insect that still live today in southern Asia, northern Indochina and Africa.
The discovery from a limestone fossil bed in north-eastern Brazil shows that the creature has undergone minimal evolutionary change since the Early Cretaceous Period.
“Schizodactylidae, or splay-footed crickets, are an unusual group of large, fearsome-looking predatory insects related to the true crickets, katydids and grasshoppers, in the order Orthoptera,” said Sam Heads, of the Illinois Natural History Survey.
“They get their common name from the large, paddle-like projections on their feet, which help support their large bodies as they move around their sandy habitats, hunting down prey.”
Although there are minor changes in the body structure, Heads said that the genus has been in a period of “evolutionary stasis” for at least the last 100 million years.
Heads said, “suggesting that the habitat preferences of Schizodactylus have changed little in over 100 million years.”
The findings are described in a paper in the open access journal ZooKeys. (ANI)
