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Me
Review by:
MegF (17
 ) Posted
Aiken, South Carolina, United States 
Owned reptile before: Yes
If yes how long: 6 years
Based on experience with: 3 snakes of this species
My pet
 Snake's name: Stubby
Time owned:
2 years
Acquired from:
Breeder (non-professional, hobby breeder)
I recommend this snake: for experts only
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Comments
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I came across a fascinating article on another species of snail eating snake - Pareas iwasakii. How it has evolved to better pull snails from their shells is amazing enough, but now it has been discovered that one species of snail has evolved in a way to counteract the snake...
"Pareas iwasakii, has lopsided jaws to better enable it to tug snails out of their shells. Most snails have shells that whirl clockwise (to the right) so P. iwasakii has evolved an upper jaw with more teeth on the right side than the left. In a sample of 28 snakes, the Hoso found each one had an average of 17.5 teeth on its left jaw and 24.9 teeth on the right.
The lack of symmetry helps the snake pry the snails out of their shells with alternate retractions of their left and right jaws, a technique called "mandible walking".
The snail, Satsuma c. caliginosa, has countered the snake's adaptation by evolving a left-handed swirling pattern.
Hoso et al. write in Biology Letters: In addition, our experiments demonstrate a defensive function of sinistrality for snails against snake predators. Sinistral variants have been generally considered to suffer selective disadvantages on account of the overwhelming predominance of dextrals (Vermeij 1975, 2002; Johnson 1982; Gould et al. 1985;
Asami et al. 1998; but see Dietl & Hendricks 2006). However, sinistrals should enjoy a selective advantage over dextrals under chirally biased predation by snakes. The remarkable diversity of sinistral snails in Southeast Asia (Vermeij 1975; Hoso et al. 2006, unpublished data) may be attributable to ‘right-handed predation’ by the snakes.
"Pareas iwasakii, has lopsided jaws to better enable it to tug snails out of their shells. Most snails have shells that whirl clockwise (to the right) so P. iwasakii has evolved an upper jaw with more teeth on the right side than the left. In a sample of 28 snakes, the Hoso found each one had an average of 17.5 teeth on its left jaw and 24.9 teeth on the right.
The lack of symmetry helps the snake pry the snails out of their shells with alternate retractions of their left and right jaws, a technique called "mandible walking".
The snail, Satsuma c. caliginosa, has countered the snake's adaptation by evolving a left-handed swirling pattern.
Hoso et al. write in Biology Letters: In addition, our experiments demonstrate a defensive function of sinistrality for snails against snake predators. Sinistral variants have been generally considered to suffer selective disadvantages on account of the overwhelming predominance of dextrals (Vermeij 1975, 2002; Johnson 1982; Gould et al. 1985;
Asami et al. 1998; but see Dietl & Hendricks 2006). However, sinistrals should enjoy a selective advantage over dextrals under chirally biased predation by snakes. The remarkable diversity of sinistral snails in Southeast Asia (Vermeij 1975; Hoso et al. 2006, unpublished data) may be attributable to ‘right-handed predation’ by the snakes.
By earthling (80) Posted January 23, 2010 12:52
) Posted January 23, 2010 12:52