November 18, 2008--Modern Alaska is a geological puzzle, a mosaic of fragments from other parts of the world.

Geologists have found striking similarities between fossil shells found in Alaska and shells from Europe and Russia that date back to the same time, the Paleozoic eras Silurian period, between 417 million and 443 million years ago.

This Spinicharybdis krizi or spiny whirlpool snail, found in the southeastern Alaska panhandle by geologist David Rohr, bristles with delicate, hollow tubular spines that Rohr says probably supported it like tripods on hard reefs.