New Cambrian 'Penis Worm' Discovered

by Megan Gannon, News Editor | May 06, 2015 12:01am ET

You might have heard of vagina dentata — the mythical"toothed vagina" born of male paranoia. But have you heard of the carnivorous penis-shaped worm known as Ottoia prolifica? This 505-million-year-old phallus-like creature actually had a throat full of teeth.

Now, scientists who took a close look at the teeth of fossilized penis worms (or priapulids) have discovered a new species.

The paleontologist Charles Walcott first discovered O. prolifica in 1911 in the Burgess Shale, a geologic formation in the Canadian Rockies that contains fossils of bizarre critters such as trilobites and velvet worms from the middle Cambrian period.

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Penis Worms Show the Evolution of the Digestive System

ScienceDaily (Oct. 26, 2012) — A team of scientists has revealed that the enigmatic marine penis worms (priapulids) develop their intestine as humans, fish or starfish. This surprising finding shows that very different animals share a common way of forming a gut.

A research team led by Dr. Andreas Hejnol from the Sars International Centre for Marine Molecular Biology in Norway, examined the formation of the gut and the expression of genes needed to form the mouth and the anus in priapulid embryos. Priapulids are an obscure group of marine worms that live in shallow waters.

"Surprisingly, priapulids form the gut like humans, fish, frogs, starfish and sea urchins -and all of them even use the same genes. It does not mean that these penis worms are now closely related to humans. Instead the fact that different animals share a common way of forming the gut suggests that the embryological origins of the human intestine and how it develops are much older than previously thought -- most likely over 500 million years, when the first bilaterally symmetric animals appeared on Earth" remarks Hejnol.

The study, featured online on the 25th of October in the journal Current Biology, represents the first description of the entire embryonic development of these enigmatic animals.

Continued:  http://www.sciencedaily.com/releases/2012/10/121026084350.htm