TimeTree is a public knowledge-base for information on the evolutionary timescale of life. A search utility allows exploration of the thousands of divergence times among organisms in the published literature. A tree-based (hierarchical) system is used to identify all published molecular time estimates bearing on the divergence of two chosen taxa, such as species, compute summary statistics, and present the results . . . For those interested in published summaries of relationships and divergence times of major groups of organisms (family level and above), see the authoritative synthesis The Timetree of Life.

Here are some examples to get you started: Humans and Chimpanzees diverged 6.3 MYA; Giraffes and Dolphins diverged 58.3 MYA; Cats and Mice diverged 95.2 MYA; and Dogs and Fleas diverged 777.8 MYA. [more inside]
posted by troll on Oct 27, 2011 - 18 comments

Holotypic Occlupanid Research Group: Taxonomic Data of the Breadties of the World [via]
posted by brundlefly on Jun 6, 2011 - 15 comments

Circus of the Spineless #50 - the 50th in a series of collections of scientists' favorite disgusting, glorious, and gloriously disgusting invertebrates. Previously
posted by Burhanistan on May 7, 2010 - 7 comments

The Encyclopedia of Life [previously] is E.O. Wilson's dream become reality. It has been online since February of 2008, aiming to catalog the currently known 1.9 million species on our planet. You can also add text, images, video, comments, and tags. [ FAQ • Video Introduction • Tutorials ]
posted by not_on_display on Jan 30, 2010 - 10 comments

What Is A Species? "To this day, scientists struggle with that question. A better definition can influence which animals make the endangered list."
posted by homunculus on Jun 8, 2008 - 11 comments

Are you annoyed that there is no species of blind cave spider named Sinopoda metafilteris or worm salamander named Oedipina bluepepsi? You can fix that for 3,000 Euros at the controversal BIOPAT. For inspiration, the Curiosities of Biological Nomenclature site collects the puns, insults, and other weirdnesses that can be found in the scientific names of various plants and animals [prev.]. Genes are not immune to weird names, especially in the case of the fruitfly, where clever naming is normal; but even better are the world's strangest dinosaur names, which allow you to tremble in fear in front of the bambiraptor and meet the Dragon King of Hogwarts.
posted by blahblahblah on Apr 9, 2007 - 13 comments

The Tree of Life.
posted by Gyan on Apr 26, 2004 - 8 comments

Mantophasmatodea! No, it's not some new sex position, it's a new order of insect life, the first one thus defined since 1914.
posted by WolfDaddy on Apr 19, 2002 - 10 comments