Web sight
At around the same time I was telling you about the coevolution of spiders and their prey scientists were reporting the discovery of the worlds oldest spider web. Preserved in a large blob of amber the web and the insects caught in it have now been dated to the early Cretaceous - about 110 million years ago.Although the web is not complete enough for scientists to reconstruct it, enough remains to suggest this was not just a collection of strands and was probably in one plane like an orb web.
As you can imagine finding fossilized spider webs is unusual. We do know that fossilized spiders have had spinnerets for producing silk for closer to 400 million years.
There is a report on the research in New Scientist magazine.
Labels: Paleontology
posted by John Latto @ 10:32 AM
2 comments
2 Comments:
a little confused about co-evolution..
does it mean that the two species would not be able to evolve without the other?
and when do they reach a limit?
Not exactly.
Coevolution describes a situation where two species are such an important selective force on each other (whether as predator and prey or host and parasite or any other relationship) that an evoltionary change in one species (say a rabbit running faster to avoid foxes) leads to a change in the other species (foxes now run faster to catch rabbits) and the cycle continues until some other limit is reached.
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