PhotoThe resulting spider tree shows a massive network of species whose ancestors began to branch away from each other hundreds of millions of years ago. PhotoDr. Hormiga and colleagues say based on this analysis that the ability to make orb webs must have arisen multiple times. On the tree, spiders that make sticky orb webs are all closely related, but the makers of non-sticky orb webs have an ancestor that didn’t use a web for hunting at all. Dr. Hormiga and colleagues write that the hypothesis that the orb web evolved once and was simply passed down “crumbles” under this evidence. Advertisement Continue reading the main story“It puts it on very solid ground that the orb web evolved more than once,” Dr. Hormiga said.

Source: New York Times April 26, 2018 17:37 UTC