Why does the same species have variations in the color pattern?
Birds are a principle predator of land snails. They use “pattern recognition” to identify prey species. If 70% of the snail shells have three spiral bands and the remainder have two or four, the birds will prey on the 70% and the remaining 30% will be safe. Variation in the shell pattern is an effective means to insure species survival from a “pattern recognition” prey.
