BIO 1130 Lecture Notes - Lecture 3: Parapatric Speciation, Sympatric Speciation, Ernst Mayer

• School: University of Ottawa
• Department: Biology
• Course: BIO 1130
• Professor: Jon Houseman

Document Summary

Advanced characters: a change in phenotype that most organisms of a group have. This will score them a 1 on the cladogram and create a separation and a branch for those who don"t have the advanced character or apomorphy. Allopatric speciation: when a physical barrier (vicariance) divides a population and they become separated. Or when dispersal occurs and organisms move to different habitats. They are isolated from each other which prevents gene flow and evolution causes the creation of two subspecies living on different sides of the divide. For example, fruit flies that live on different hawaiian islands and have developed due to different natural selection create many different species. Anagenesis: linear sequence that describes the rate of evolutionary change in a species. It is a sequence that goes very slowly over time and species have possibility of overlap. Advanced condition that most organisms have that is a change over time from the original organism.