Carl Zimmer’s Loom has a great story up about why a group of tiny daddy-long-legs relatives, the Petallidae, is so widely distributed across the world. Check it out!

“Below is a map of where other species of Petallidae can be found. They seem to be scattered randomly across the world. But petallids are terrible at dispersing…..And they live only on ancient continent crust. Petallids live on Sri Lanka and on Madagascar. But they live on none of the young volcanic islands in between–or anywhere else in the world, for that matter. So they couldn’t have swum or flown to their farflung locations. Yet DNA evidence clearly shows that the petallids all descend from a common ancestor. So, how did they get there?”

His article also has links to the original research.

Edited 8/30/07 to add: the photo on the right in the NYT article is *not* a petallidae, or even an Opiliones. It is a spider. (One known as a daddy-long legs spider, in fact, (Pholcidae) which is how the error was probably made.)