|
Monarch butterflies, Danaus plexippus, are known for their lengthy migrations, but in some cases the insects have spread outside their normal range and settled in non-migrating populations. These non-migrating butterflies consistently have smaller wings (bottom, collected in S. America) than migrators (top, collected in San Francisco).
|
Two Centuries of Monarch Butterflies Show Evolution of Wing Length - Egghead
A couple more examples of evolution in progress being reported on by biologists who had no intention of refuting Creationism, but did so anyway simply by reporting the facts.
The first example is of the
monarch butterfly, Danaus plexippus. These North American butterflies are famous for their prodigious migration flights to a small valley in Mexico where they spend the Winter, then out across North America to their breeding grounds in Spring. Those west of the Rocky Mountains also over-winter in sites in Southern California although some do go to Mexico.
Over the years, small populations have been established on Caribbean and Pacific islands, Hawai'i, Australia and in South America, where, because the Winter climate is milder, they have given up migrating and become sedentary species. These colonies have been founded by windblown vagrants. I have even seen them in Puerto Banús, on the southern coast of Andalusia, Spain, where there is a healthy local population.