BIOL 1108 Lecture Notes - Lecture 8: Allopatric Speciation, Polyploid, Speciation
Document Summary
Core concept 4: speciation can occur with or without natural selection. Instantaneous speciation: oh, those crazy plants: new species different then mom or dad. In allopatry, drift can drive a lot of change which is non-adaptive by its very definition (because it is random in when, where and how, it appears) therefore, natural selection does not always lead to speciation. Natural selection in speciation: sympatric (disruptive natural selection) This must be very strong to keep the speciation process moving along. Need a wide range of phenotypes for this to work: allopatric (and adaptive radiation) facilitated by natural selection. A slower accumulation of differences between the two populations: reinforcement of reproductive isolation. Speciation can occur with or without natural selection: this is a true statement. It is not the strongest or smartest species who survive the speciation process, it is the species that are most responsive to change.
