HEIKEGANI IN COSMOS BY CARL SAGAN
HEIKEGANI IN COSMOS BY CARL SAGAN, Heikegani 平家蟹 ヘイケガニ is a species of crab native to Japan with a shell that bears a pattern resembling a human face It is locally believed that these crabs are reincarnations of the spirits of the Heike warriors defeated at the Battle of Dan no ura as told in the Heike Monogatari The Tale of the Heike The pattern of ridges on the carapace serves a very functional purpose as sites of muscle attachment Similar patterns are found on species in many parts of the world including fossilized remains Heikegani were used by Carl Sagan in his popular science television show Cosmos: A Personal Voyage as an example of unintentional artificial selection However some experts have questioned this The story goes that the crabs with shells resembling Samurai were thrown back while those not resembling Samurai were eaten giving the former a greater chance of reproducing 1 However the maximum width of adult heikegani crabs is only about 30 mm 1 2 inches so some fishermen throw these crabs back into the sea regardless of appearance But smaller specimens may have been eaten in the past before mass fishing It is difficult to know for sure how much of the crabs shape and quantity has been dictated by artificial selection Wikipedia