PDF - Wallace Online

v COLOURS OF ANIMALS 349Protective colours.2.Wamingcoloun. { J gSSBCSSSBi, ..3. Sexual colours.{1. 4. Normal colours. 1Plants 5. Attractive colours.It is now proposed, firstly, to point out the nature of thephenomena presented under each of these heads; then toexplain the general laws of the production of colour innature ; and, lastly, to show how far the varied phenomenaof animal coloration can be explained by means of thoselaws, acting in conjunction with the laws of evolution andnatural selection.Protective ColoursThe nature of the two first groups, protective and warningcolours, has been so fully detailed and illustrated inmychapter on "Mimicry and other Protective Eesemblancesamong Animals," that very little need be added here excepta few words of general explanation. Protective colours areexceedingly prevalent in nature, comprising those of all thewhite arctic animals, the sandy -coloured desert forms, andthe green birds and insects of tropical forests. It also comprisesthousands of cases of special resemblance of birds tothe surroundings of their nests, and especially of insects tothe bark, leaves, flowers, or soil, on or amid which theydwell. Mammalia, fishes, and reptiles, as well as molluscaand other marine invertebrates, present similar phenomena;and the more the habits of animals are investigated, the morenumerous are found to be the cases in which their colourstend to conceal them, either from their enemies or from thecreatures they prey upon. One of the last -observed andmost curious of these protective resemblances has been communicatedto me by Sir Charles Dilke. He was shown inJava a pink -coloured Mantis which, when at rest, exactlyresembled a pink orchis-flower. The mantis is a carnivorousinsect which lies in wait for its prey ; and, byits resemblanceto a flower, the insects it feeds on would be actually attractedtowards it. This one is said to feed especially on butter-1Many, or perhaps all, of these are now believed to be diversely colouredfor purposes of recognition. See Darwinism, p. 217.