Speciation The formation of a new species

Speciation- occurs in isolated populations Geographic isolation leads to reproductive isolation Once the population is geographically isolated, they adapt to their unique environment. If they can no longer breed with the original larger population they are considered a separate species.

Ex: Galapagos Finches 1.Finches on the mainland migrate along the coast 2.Blown off course, they landed on the Galapagos Islands. 3.With lots of food an no predators their population increased. 4.They spread to the other islands.

5. They adapted to the conditions on the separate islands. (mutations caused different bills) 6. The Finches became separate species once they no longer reproduced with those whose bill was different.

Ex: Death Valley Fish 1.Once a large lake filled the valley, with one large fish population. 2.As the climate changed the lake dried up. 3.The fish became isolated in separate ponds and adapted to local conditions. 4.They are now separate species.

Devil’s Hole Pupfish Salt Creek Pupfish

Divergent evolution: One species becomes many Ex: Darwin’s Finches also called: adaptive radiation

Convergent evolution: unrelated species become similar because they adapt to the same habitat placental mammal vs marsupial white tail deer kangaroo