First Sex was Sideways

Tue, 10/21/2014 - 07:15
Submitted by Carlin Ross

This is an image of the Antiarch - a 380 million year old lake fish that was the first creature to have "sex". 

A researcher was looking through some Antiarch fossils and noticed a distinct L-shaped bone (penis).  Then he found want looked like a cheese grater set of bones (vulva) and realized that the Antiarch had evolved to have penetrative sex and internal copulation.  And they had sex side-by-side locking together their genitals; the first sex was side-ways.  Their little side appendages evolved to help the male insert his penis while floating in water.

Researcher John Long:

“We’ve often wondered, for over 100 years, what these tiny little jointed arms were used for in these very peculiar fish. Now we know that if your sexual organs are rigid and fixed to your whole body, then little arms are very useful for helping to link the male and female together.

The male can get his large L-shaped sexual organ into the right position to dock with the female genital plates, which are like cheese graters – very rough – so they act like Velcro, locking the male organ into position to transfer sperm.”


Editor in Chief & Keeper of All Things Betty Dodson

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Oh ...

Tue, 10/21/2014 - 10:37
barn dog

baby ... We begin in a 'sea' to become walking warm worms with a sea inside wagging & waging !! ~~~ :>)

The original article was

Walter's picture
Tue, 10/21/2014 - 10:43

The original article was published in Nature and an animation of the "sex" can be seen on YouTube at