Polymorphism and Population Density in the African Land Snail, Limicolaria martensiana

Science  10 May 1963:
Vol. 140, Issue 3567, pp. 666-667
DOI: 10.1126/science.140.3567.666


In natural populations of the African land snail, Limicolaria martensiana, the degree of polymorphism in color and pattern may vary with the density of the population. This could occur because predators eat the snails selectively and use past experience as a guide in finding further prey. Hence contrasting color forms may be at an advantage in dense populations where predators would have ample opportunity to learn to recognize prey.