Thursday, August 6, 2009

Ancient Arachnids in 3D ↦

A new imaging technique brilliantly reveals two ancient ancestors of modern-day spiders (and other arachnids):

Scientists at Imperial College London have created detailed 3D computer models of two fossilised specimens of ancient creatures called Cryptomartus hindi and Eophrynus prestvicii, closely related to modern-day spiders. The study reveals some of the physical traits that helped them to hunt for prey and evade predators.

Both Cryptomartus hindi and Eophrynus prestivicii were around the size of a 50 pence piece and they roamed the Earth during the Carboniferous period, 359 – 299 million years ago. This was a time before the dinosaurs, when life was emerging from the oceans to live on land. During this period, the world’s continents were merging together near the equator to form one supercontinent and the first tropical rainforests were playing host to a diverse range of species.

These detailed models are already providing important insight into the evolution of arachnids:

The computer models also revealed that Cryptomartus hindi’s mouth appendages, called pedipalps, had tiny ‘tarsal’ claws attached at the end to help the creature to manipulate its prey. These claws are seen in rare modern-day arachnids such as the Ricinulei. The researchers say that the existence of this common physical feature, shared by the Cryptomartus hindi and the Ricinulei, lends further weight to the theory that they are closely related.