Heikegani
| Heikegani | ||||||||||||
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Heikegani with a human-like face on the carapace . Detail from a color woodcut by Kuniyoshi , around 1840 |
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| Scientific name | ||||||||||||
| Heikea japonica | ||||||||||||
| ( from Siebold , 1824) |
Heikegani ( Heikea japonica ) is a species of crab from Japan whose back armor is so furrowed that it resembles a human face. They occur mainly in the southwestern part of the main island of Honshu in the Shimonoseki Strait .
features
The crabs have a convex carapace that is slightly wider than it is long. The branchial and branchocardial furrows are very distinct, the cervical furrow is somewhat less deep. The exorbital teeth are well developed. In adult males, the right scissors are significantly enlarged, while both scissors are the same size in females and young males. The second and third pair of legs are very long and slim.
origin of the name
According to the work Heike Monogatari , many warriors of the Heike clan defeated in the sea battle of Dan-no-ura on April 25, 1185 are said to have committed collective suicide together with their leader by drowning themselves in the sea before being captured or killed by the enemy could become. Over time, the popular belief emerged that the crabs were reincarnations of the dead Heike warriors and that the armor on the back showed the facial expression of an angry samurai .
Discussion of unintentional selection
In 1953, Julian Huxley argued that this type of crab was an example of unintentional human selection: the more the armor looked like a human face, the more likely the fishermen would throw such a crab back into the sea. Through this selection, the characteristics of the armor would emerge even more clearly over time. The thesis was also popularized by Carl Sagan in his book Cosmos .
However, this theory is questioned: Due to the small size of the crabs (approx. 2-3 cm), they are not intended for consumption and are not deliberately selected by the fishermen. The characteristic bulges of the back armor are merely reinforced attachment points for muscles and do not represent a feature that changes independently.
Individual evidence
- ↑ Marine Species Identification Portal: Heikea japonica
- ↑ a b c Joel W. Martin: The Samurai Crab . In: Terra . Vol. 31, No. 4 , 1993, p. 32 ( PDF ).
Web links
- the last fight
- Clemente Nobrega: Caranguejos samurais . In: Ideias e Inovação . Editora Globo (Portuguese, direct comparison photo between a samurai face and the photo of a Heikegani)
- Evolución: La Leyenda de los Heike in MGBlog (Spanish, additional pictures)