Neo-Darwinian Theory
The Neo-Darwinian theory is not one proposition but several
- The first proposition is that populations of organisms have evolved. Species on earth today are the descendants of other species that lives earlier, and the change in these lineages has been gradual, taking thousands to millions of years.
- The second proposition is that new forms of life are continually generated by the splitting of a single lineage into two or more lineages. About five million years ago, a species of primates split into two distinct lineages: one leading to modern chimpanzees and the other to modern humans.
- The third proposition is that most of evolutionary change is probably driven by natural selection: individuals carrying genes that better suit them to the current environment leave more offspring than individuals carrying genes that make them less adapted.
