BIOLOGY 1M03 Lecture Notes - Lecture 12: Disruptive Selection
18 Oct 2015
School
Department
Course
Professor
Document Summary
Allopatric speciation: if there is a barrier to gene flow, populations that live in the same place, sympatric populations can become isolated. occurring, requires strong natural selection acting on each population differently, genetic isolation by different habitat preferences, sympatric speciation: speciation that occurs when gene flow is possible but not, example of sympatric speciation is maggot flies, were recently diverged species, that live in the same habitats but specialize on diff fruit (one on apples one on hawthorns, native hawthorn maggot flies began to specialize on new food, such as apples. Tetraploids are the offspring of a parent that produced diploid gametes and then self fertilized: in general tetraploids breed with each other but not other diploids, haploid (cid:224) one copy of each chromosomes, diploid (cid:224) two copies of each chromosomes, triploid (cid:224) three copies of each chromosomes, the gametes of a triploid individual rarely contain the same number of each chromosome.
