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The Vegan Marxist
6th February 2011, 20:48
http://www.sciencedaily.com/images/2011/02/110203113758-large.jpg
A fossil found in northeastern Brazil confirmed that the splay-footed
cricket of today has at least a 100-million-year-old pedigree. (Credit:
Hwaja Goetz)

Rare Insect Fossil Reveals 100 Million Years of Evolutionary Stasis

ScienceDaily (Feb. 4, 2011) — Researchers have discovered the 100 million-year-old ancestor of a group of large, carnivorous, cricket-like insects that still live today in southern Asia, northern Indochina and Africa. The new find, in a limestone fossil bed in northeastern Brazil, corrects the mistaken classification of another fossil of this type and reveals that the genus has undergone very little evolutionary change since the Early Cretaceous Period, a time of dinosaurs just before the breakup of the supercontinent Gondwana.

The findings are described in a paper in the open access journal ZooKeys.

"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 University of Illinois entomologist and lead author 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 the fossil is distinct from today's splay-footed crickets, its general features differ very little, Heads said, revealing that the genus has been in a period of "evolutionary stasis" for at least the last 100 million years.

Other studies have determined that the region where the fossil was found was most likely an arid or semi-arid monsoonal environment during the Early Cretaceous Period, Heads said, "suggesting that the habitat preferences of Schizodactylus have changed little in over 100 million years."

http://www.sciencedaily.com/releases/2011/02/110203113758.htm

Widerstand
6th February 2011, 21:14
I always knew that insects are some next-level shit. They don't even need no evolution.

ÑóẊîöʼn
6th February 2011, 23:03
Seems to be a case of of evolution hitting upon a body shape that works, combined with a distinct lack of evolutionary pressure to change morphology (there may be internal differences between the present and ancestral forms that I am not aware of).

smk
7th February 2011, 03:11
this is evidence of punctuated equilibrium (how strange I just talked about this in another post.)

http://upload.wikimedia.org/wikipedia/commons/6/69/Punctuated-equilibrium.svg

This theory of evolution states that there are long periods of stasis, then rapid periods of evolution, followed by more stasis. I'm pretty sure that Darwin was a gradualist.