The Paleontology was Unsettled

Male (left) and female he created them. (Economist photo)

After noting that most fish "simply broadcast eggs and sperm into the water and hope that these will meet" paleontologists hypothesized that sexual intercourse developed when creatures moved ashore.

A mollusk that lived 400 million years ago has upended that theory. Paleontologists observed that males of the presciently-named Microbrachius dicki

have special bony claspers that would, when the animal was alive, have held a female close for mating, while others (presumably female) have dermal plates corresponding to these claspers that would have allowed their paramours to get a good grip.

Today claspers can be found in male sharks and other fish. Perhaps the lyricist should have included the humble mollusk when he sang

Cold Cape Cod clams, 'gainst their wish, do it
Even lazy jellyfish do it
Let's do it, let's fall in love