module 12 lesson 2

1. Stabilizing

Favors average individuals in the population

Reduces variation of individuals in a population

http://Muskopf, Shannan. Online Images. The Biology Corner. 13 May 2007. www.biologycorner.com/bio2/notes_chap16.html

•Favors 1 extreme of individuals in the population•Those having the extreme trait survive and reproduce •Causes the population to move in one direction because more

individuals have the trait

Muskopf, Shannan. Online Images. The Biology Corner. 13 May 2007. http://www.biologycorner.com/bio2/notes_chap16.html

•Favors either extreme of individuals in the population (unlike directional selection which favors one extreme)•Those 2 extremes of the population survive and reproduce•Leads to no intermediate (average) form of the trait •Two new species evolve

Online Images. Biofundamentals. 13 May 2007. http://virtuallaboratory.net/Biofundamentals/lectureNotes/Topic1F_Evo.htm

Muskopf, Shannan. Online Images. The Biology Corner. 13 May 2007. http://www.biologycorner.com/bio3/notes-chap17.html

Organisms from the same species develop different traits to survive their environment.Adaptive Radiation: This is a type of divergent evolution where a species evolves to fit into an open niche.

http://www.biology-online.org/2/15_adaptive_radiation.htm

Causes of speciation:•Behavioral Isolation: occurs when two species have different courtship behaviors (males have courtship songs or dances that will only be recognized by females of the same species)

•Geographic Isolation –

physical barrier (river, mountain) prevents contact between individuals and leads to speciation

Spotted owl subspecies living in different geographic locations show some genetic and morphological differences. This observation is consistent with the idea that new species form through geographic isolation.

http://evolution.berkeley.edu/evolibrary/article/_0_0/evo_45

These organism are not from the same species, and they are not related. They developed similar adaptations because they have the same niche. They all eat ants.

http://www.pbs.org/wgbh/evolution/library/01/4/l_014_01.html

Yucca flowers are a certain shape so that only the yucca moths can pollinate them. http://biology.clc.uc.edu/Courses/Bio303/coevolution.htm