But most of the tales and impressions concerned a relatively late race, of a queer and intricate shape, resembling no life-form known to science, which had lived till only fifty million years before the advent of man. This, they indicated, was the greatest race of all because it alone had conquered the secret of time. - The Shadow Out of Time, HPL.
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23 December 2008
The species once described as the world's oldest spider is a more primitive version of the web-spinning modern spider, scientists have found.
Most of what the group initially found among fossil remains belonged to a group of extinct arachnids called trigonotarbids, but one bit seemed to have the modified hairs called spigots from which spider silk emerges, as well as the external, flexible appendages known as spinnerets that facilitate web-spinning.
That led the group to believe they were looking at the world's oldest known spider.
The process of identifying the fossilised spider parts started with solid rock that was dissolved in acid, leaving behind organic matter that was sifted through to determine which belong to animals or plants.
"They're all microscopic fragments. What you've got is a jigsaw puzzle, with half the pieces and no picture on the box lid," Professor Selden said.
"You don't know what it's going to be if you haven't got all the pieces, so having these additional pieces means it changed the idea of what it was."
The finding is important for evolutionary biologists trying to unravel the origin of spider silk.
To clean up the incomplete record of different species, the team has suggested a new order be instituted, containing the Attercopus and Permarachne species.
http://news.bbc.co.uk/2/hi/science/nature/7795897.stm
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