Darwinopterus - Modular Evolution

[Orleander]

What does this mean? Does this mean on one kind of animal evolves this way or a whole group of animals evolve this way over a certain time frame?

New Dino-Eating Pterosaur Evolved in Unusual Way

Oct. 13, 2009 -- An international team of researchers has just identified a new dinosaur-eating pterosaur that soared through the Jurassic skies 160 million years ago, according to a study released this week.

Christened Darwinopterus modularis, meaning "Darwin's wing composed of interchangeable units," the new flying reptile honors the 200th anniversary of Charles Darwin's birth by providing evidence for an unusual and controversial type of evolution.

Modular evolution theory holds that entire modules, or groups of body features, evolve together within a relatively short period of time.

Lead author Junchang Lu told Discovery News that the pterosaur fills a gap between primitive basal forms of this animal and more advanced pterodactyl types.

Older forms had "small heads, short necks, short wrists, a long tail and a long fifth toe on the foot," he said. In later, more derived types, "the skull, neck and wrist became relatively long, but the tail became short and the fifth toe dwindled to a small nub or was lost altogether."

Lu added: "Darwinopterus captures a moment in that evolution from primitive to advanced forms. But contrary to what we expected, it has the head and neck of an advanced pterodactyloid while the rest of the skeleton is like that of the primitive rhamphorhynchoids (flying reptiles)."....

 

[Idle Mind]

"Traditional" evolution would have expected that an intermediate fossil would have had a head/neck that was in between "primitive" and "advanced" forms. So, a slightly longer head, slightly longer neck, slightly longer wrists, etc. All features would be gradually moving from the primitive form to the advanced form as time went. This find, a transitional fossil with a primitive wing structure but advanced head/neck, shows that parts of the body can evolve at different rates.

 

[Orleander]

ah, thank you Idle Mind!

 

[Idle Mind]

I didn't get a chance to proofread because I'm at work. I'm just glad it was coherent.

 

[Michael]

Darwinopterus

Darwinopterus

A very rare find of some 20 fossilized pterodactyls has produced the first clear evidence of a controversial theory of evolution. The creature's discovery has astounded scientists because their age puts them within two recognized groups of pterodactyls -- primitive long-tailed forms and advanced short-tail forms -- and they display characteristics of both.

The combination of features indicates that the primitive pterodactyls evolved relatively quickly, and that certain groups of features changed at the same time.

Traditional evolutionary theory suggests that one feature -- a tail for instance -- would slowly evolve over time.

"Darwinopterus came as quite a shock to us," said David Unwin, from the University of Leicester's School of Museum Studies, which identified the creature, along with researchers from the Geological Institute of Beijing.

"We had always expected a gap-filler with typically intermediate features such as a moderately elongate tail -- neither long nor short -- but the strange thing about Darwinopterus is that it has a head and neck just like that of advanced pterosaurs, while the rest of the skeleton, including a very long tail, is identical to that of primitive forms," he said.

By comparing the fossil with others from earlier and later periods, scientists have been able to sketch a rough timeline of the pterodactyl's progression. more at CNN....

 

[draqon]

so it shared two different features, whats the big deal? Maybe it was a different subspecies.