BIOL 3200 Lecture Notes - Lecture 4: Sympatric Speciation, Allopatric Speciation, Spiritualism
Document Summary
Dissent from darwin: darwin convinced many of his contemporaries of evolution but not that natural selection was the principal mechanism. Eclipse of darwinism: between 1860 and 1930. Several issues in regard to selection theory: natural e(cid:448)olutio(cid:374) (cid:272)ould (cid:374)ot a(cid:272)(cid:272)ou(cid:374)t for the dire(cid:272)tio(cid:374) of e(cid:448)olutio(cid:374) this (cid:449)as la(cid:373)ar(cid:272)k"s thinking as well, evolution is not purposeful. Blending inheritance: variations seemed to be blends of characteristics inherited from both parents. Are species real: some people thought it was illogical that species are not real, agassiz was one of them. Are all evolved traits adaptations: darwin added the concept of sexual selection to account for features such as eye colour, these traits are not useful for struggle for existence, but are useful for attracting mates. Abundant evidence for evolution but there were alternative theories: three common alternatives, neo-lamarckism, orthogenesis: straight line evolution, saltationism: evolution by leaps. Emergence of neo-darwinism: neo-darwinism is solely based on natural selection.
