Evolution
Porcelain crabs are an example of carcinisation, whereby a non-crab-like animal (in this case a relative of a squat lobster) evolves into an animal that resembles a true crab. Porcelain crabs can be distinguished from true crabs by the apparent number of walking legs (three instead of four pairs, the fourth pair is reduced and held against the carapace), and the long antennae originating on the front outside of the eyestalks. The abdomen of the porcelain crab is long and folded underneath it, free to move.
Read more about this topic: Porcelain Crab
Famous quotes containing the word evolution:
“By contrast with history, evolution is an unconscious process. Another, and perhaps a better way of putting it would be to say that evolution is a natural process, history a human one.... Insofar as we treat man as a part of nature—for instance in a biological survey of evolution—we are precisely not treating him as a historical being. As a historically developing being, he is set over against nature, both as a knower and as a doer.”
—Owen Barfield (b. 1898)
“Historians will have to face the fact that natural selection determined the evolution of cultures in the same manner as it did that of species.”
—Konrad Lorenz (1903–1989)
“The more specific idea of evolution now reached is—a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
—Herbert Spencer (1820–1903)