Elements of biology; a practical Elements of biology; a practical text-book correlating botany, zoology, and human physiology elementsofbiolog00hunt Year: [c1907] The monarch and viceroy butterflies; the latter (at the right) is a mimic. hundred miles at sea. They may migrate southward upon th€ approach of the cold weather. Some com- mon forms, as the mourning cloak (Va- nessa antiopa), hiber- nate in the North, passing the cold weather under stones or overhanging clods of earth. Mimicry. — The monarch butterfly is an example of a race which has received protection from enemies in the struggl
Elements of biology; a practical Elements of biology; a practical text-book correlating botany, zoology, and human physiology elementsofbiolog00hunt Year: [c1907] The monarch and viceroy butterflies; the latter (at the right) is a mimic. hundred miles at sea. They may migrate southward upon th€ approach of the cold weather. Some com- mon forms, as the mourning cloak (Va- nessa antiopa), hiber- nate in the North, passing the cold weather under stones or overhanging clods of earth. Mimicry. — The monarch butterfly is an example of a race which has received protection from enemies in the struggle for life, because of its nauseous taste and, perhaps, because its caterpillar feeds on plants of no commercial value. Another butterfly, less favored by nature, resembles the monarch in outward appearance. This is the viceroy (Basilarchia archip- pus). It seems probable that in the early history^ of the species called viceroy some of this edible form escaped from the birds because they resembled in color and form the species of inedible monarchs. These favored individuals produced new butterflies which resembled the monarch more closely. So for generation after generation the ojies which were most like the inedible species were left, the others becoming the food of birds. Ultimately a species of butterflies was formed that owed its existence to the fact that it resembled another more favored species. This is known as mimicry, and the viceroy is called a mimic. Dimorphism and Polymorphism. — It has been found that, when a but- terfly produces two broods during one season, the individuals in these broods may differ considerably from one another. The tiger swaliow-tail is an example. It has also been found that, if the early pupae are kept in an ice box during part of the summer and then allowed to hatch out with the pupae of the second brood, the forms are then ahke in appearance. It would Hornet mimicked by locust-borer, a beetle. thus seem that the same factors
Size: 1798px × 1112px
Photo credit: © Bookworm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: archive, book, drawing, historical, history, illustration, image, page, picture, print, reference, vintage
