1. The Origin of Species

2. understanding speciation video http://www.5min.com/Video/Understan ding-Speciation-150610251 ???http://www.5min.com/Video/Understan ding-Speciation-150610251

3. Speciation Species – population sharing a gene pool - group of organisms which can interbreed Speciation – changes in a population so that it can no longer breed with other populations of the same original species. Due to Genetic drift (chance) or Natural selection (not chance) in a population

4. Macroevolution is the origin of new species Microevolution is genetic variation within a species. A species is a population or group of populations whose members have the potential to interbreed with one another and produce viable offspring, but who cannot produce viable offspring with other species. Problems with this definition Breeds? eg dogs Extinct species? Cryptic species? (appear identical, but reproductively isolated)

5. The biological species concept is based on inter- fertility, rather than physical similarity.

6. Modes of speciation Modes of speciation 1. Allopatric speciation populations geographically separate. Gene flow is interrupted. 2. Sympatric speciation geographically overlapping populations. Chromosomal changes / nonrandom mating reduce gene flow. reproductively isolated Species arise when individuals in a population become reproductively isolated one from the other.

8. Videos Wolfe: What is a species? http://www.youtube.com/watch?v=LEG Qu3cm3CEhttp://www.youtube.com/watch?v=LEG Qu3cm3CE