Search results
Results from the WOW.Com Content Network
[17] [18] They argued further that there was a "pre-Mendelian" phase of the evolution of animals, involving physical forces, before genes took over. [ 17 ] [ 19 ] Darwinian biologists freely admit that physical factors such as surface tension can cause self-assembly , but insist that genes play a crucial role.
The current theory of evolution, the modern evolutionary synthesis (or neo-darwinism), explains that evolution of species occurs through a combination of Darwin's mechanism of natural selection and Gregor Mendel's theory of genetics as the basis for biological inheritance and mathematical population genetics. [80]
The theory of evolution explains these homologous structures: all four animals shared a common ancestor, and each has undergone change over many generations. These changes in structure have produced forelimbs adapted for different tasks. [49] The bird and the bat wing are examples of convergent evolution.
Evolution is the change in the heritable characteristics of biological populations over successive generations. [1] [2] It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. [3]
Two useful introductions to the fundamental theory underlying the unit of selection issue and debate, which also present examples of multi-level selection from the entire range of the biological hierarchy (typically with entities at level N-1 competing for increased representation, i.e., higher frequency, at the immediately higher level N, e.g., organisms in populations or cell lineages in ...
For example, the Out of Africa theory of human origins, which states that modern humans developed in Africa and a small sub-population migrated out (undergoing a population bottleneck), implies that modern populations should show the signatures of this migration pattern. Specifically, post-bottleneck populations (Europeans and Asians) should ...
Adaptationism is an approach to studying the evolution of form and function. It attempts to frame the existence and persistence of traits, assuming that each of them arose independently and improved the reproductive success of the organism's ancestors.
The following approaches can all be seen as exemplifying a generalization of Darwinian ideas outside of their original domain of biology. These "Darwinian extensions" can be grouped in two categories, depending on whether they discuss implications of biological (genetic) evolution in other disciplines (e.g. medicine or psychology), or discuss processes of variation and selection of entities ...