T is for Triassic

The Triassic period lasted from about 250 million years ago to about 200 million years ago and was a transitional period betwen the Paleozoic Era and Mesozoic Era. At the beginning of the Triassic, the world land masses were still joined as one in a formation we know as Pangea. By the end of the Triassic and the beginning of the Jurassic, Pangea had begun breaking up. The Triassic ended with a major extinction event that was especially severe on ocean species. The Triassic was especially transitional for life on Earth as many old species died out and newer species came into existence. While it wasn't until the extinction of the dinosaurs much, much later that mammals really flourished, it was at the very end of the Triassic that the first mammals began to appear. The Triassic was the beginning of the "Age of Reptiles."

X is for Xiphosuran

Xiphosuran are anthropods of the Xiphosura order, living and extinct. The only living xiposurans are four species of horseshoe crabs. Horseshoe crabs are called "living fossils" because really they haven't changed since about 250 million years ago (around the early Triassic period). Xiposurans were most prolific and diverse during the Paleozoic Era.

For those that don't know, painted_wolf is currently working as a research assistant helping on experiements to study the circatidal and circadian rhythms of locomotion in Limulus polyphemus. Basically that's a fancy way of saying their looking to see how daylight and tidal patterns affect the activities of the horseshoe crab. Aside from being rather cool stuff, it's important because horseshoe crab populations are on the decline and it's possible that information learned from these experiements might be useful in saving the horseshoe crab.

Z is for Zyzzyva

Zyzzyva is an American weevil (a type of beetle). The word zyzzyva is the last word in many English dictionaries so it is sometimes used to mean "the last word." This is why the magazine ZYZZYVA has the slogan "The Last Word." ZYZZYVA is a journal of West Coast writers and artists published out of San Fransisco since 1985 and edited by Howard Junker.