Types of Natural Selection

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Presentation transcript:

Types of Natural Selection

Directional selection One extreme is better Ex. length of an anteaters tongue

Diversifying selection Opposite extremes are favored Ex. White shell or Dark shell

Stabilizing selection The average is best Ex. Field mouse size

Types of natural selection

Sexual selection Picking a mate based on secondary sexual characteristics EX. Tail of peacock

Sexual dimorphism Difference in appearance between males and females Males tend to be more colorful

Males tend to be shorter Ex. Praying mantis

Diamond back terrapins Males smaller

Or just weird to us humans

More sexual dimorphism

Intrasexual selection Competition between individuals of same sex Ex. Rams, elephant seals

Fight for Harem

Inter sexual selection (mate Choice) One sex is choosy about selecting mates Ex Bower bird makes fancy bower to attract mate

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