- Comparative anatomy—Closely related organisms share anatomical similarities. American deer, bears, and men have bone structure and musculature that are remarkably similar. Apes and humans are even closer. Molecular biological studies have confirmed the direct correlation of many structures in related species even over very extensive periods of evolutionary history.
- Artificial Selection—Perhaps the most obvious evidence of evolution is the process of breeding of agricultural plants and animals. A multitude of different rices, wheats, apples, dogs, cattle, horses, etc. have had their interbreeding intentionally controlled and modified by human intervention to produce offspring that fit a purpose desired by the human. This process is a relatively rapid and predictable one.
- Ecology-Biogeography—Isolated populations such as sparrows in the Americas have taken on the characteristics that helped them to adapt to their surroundings. Northern sparrows, adapting to shorter seasons, less easily available food, and colder winters are larger and darker than their southern counterparts. Male fish living in waters with heavy predator fish populations tend to live near the bottom of the waterway and to be less colorful since predators are attracted to more brightly colored males. Recently (2003) discovered “little people”, Homo floresciensis, found on the eastern Indonesian island of Flores, 300 miles east of Java, by paleoanthropologists Mike Morwood and Peter Brown demonstrate the effects of isolation on evolution.
original fossils of Pithecanthropus erectus (now Homo erectus) found in Java in 1891 (Photo credit: Wikipedia)
The nine specimens discovered in Liang Bua cave, age-dated to only 18 KYA, included children and an adult female one meter tall with a head the size of a grapefruit. The dwarf hominids (3 meter tall adults with 380 ml braincase size) have all of the characteristics, other than size, of Homo erectus, an extinct humanoid. They made small, sophisticated tools and used fire. The island was isolated by surrounding water 2.6 million years ago, and the animals, including the hominids, left there adapted. Animals larger than rabbits became smaller like the people. An extinct pygmy elephant species called, Stegodon, adapted to become smaller due to a lack of food and an absence of predators. Animals smaller than rabbits adapted to be able to obtain more food by becoming larger, e.g. Komodo dragons, giant lizards, and giant turtles. Isolation and species limitation is the common experience; it is unusual to find a single species widely spread throughout the world. On the contrary, there is a truly remarkable diversity of species. continued…
