Jay Leno

The exciting news about the oldest known fossil that is clearly a male is not only exciting to scientists, but Gothamist imagines that comedians have sharpened their pencils in anticipation of such a story. Apparently, the fossil of a 425 million year old ancestor was found in Britain, revealing not only its gills and advanced circulatory system, but also a defined penis. The scientists named the old school water flea, "Colymbosathon ecplecticos," aka which means "swimmer with a large penis." University of Leceister's David Siveter says, "It is certainly the oldest penis in the world, that's for certain." Ah, the jokes are writing themselves!

Tonight on the Tonight Show (Dave and Conan are in reruns): Alicia Keys with Andre 3000.