Wednesday, December 3, 2008

New Giant Toothless Pterosaur Species Discovered

A researcher at the University of Portsmouth has identified a new species of pterosaur, the largest of its kind to ever be found. It represents an entirely new genus of these flying reptiles that ruled the skies 115 million years ago.

The finding is significant because it originated in Brazil and is the only example of the Chaoyangopteridae, a group of toothless pterosaurs, to be found outside China and is the largest one ever discovered.

Mark Witton identified the creature from a partial skull fossil from which he was able to estimate that it would have had a five-metre wingspan – bigger than a family car - and would stand over one metre tall at the shoulder.

He said: “Some of the previous examples we have from this family in China are just 60 centimetres long – as big as the skull of the new species. Put simply, it dwarfs any chaoyangopterid we’ve seen before by miles.”

Witton has christened the new species Lacusovagus, meaning ‘lake wanderer’, after the large body of water in which the remains were buried. ... - sd

The more fossils we find, the more the details of evolution come into focus. But it is a slow process because conditions which create fossils are very rare and most animals decompose entirely.
How are fossils formed?

There are two major requirements for an organism to be preserved as a fossil:

1. It must possess hard parts,

2. It must undergo rapid burial in a protective medium.

map of the likely Homo habilis geographic rangeFlesh is subject to extremely rapid decay, and is rarely preserved in fossils; among the few exceptions are the frozen mammoths of Siberia and Alaska, and a rhinoceros found in oil sands in Poland. Thus, under normal circumstances, only animals possessing hard parts of shell, bone or chitin (the hard matter in insects) are capable of preservation as fossils. Rapid enclosure in a protective medium is necessary to protect hard parts from the destructive action of scavengers and the weather. This protection is usually accomplished by burial in waterborne sediments, thus giving aquatic, particularly marine, forms of life the best chance of fossilisation. Terrestrial animals have comparatively little chance of preservation unless washed into lakes, as the land surface is largely an area of erosion. - cartage

This is why many transitional species from our own evolution are still missing. (But enough exist to show that evolution did occur!)  If you read Gilgamesh, it seems that dead people were just left outside to decompose in ancient times. Burial is not common in the animal kingdom. Besides modern humans, only Chimpanzees and elephants are known to throw leaves and branches over fallen members of their family groups. Neanderthals were the first to bury their dead. Some view them as a subspecies ohters as a separate species. Time will tell as we learn more.

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