WEIT Chap6

First of all, sex is good.

HOW SEX DRIVES EVOLUTION

First of all... sex is good... Pierre.brawand 19 avril 2011 à 22:36 (CEST)

What is sexual selection?

Sexual selection is a natural process that occurs in animals just before mating: it's a selection that increase an individual's chance of getting a mate. There are two forms.

1) Male-male competition (The Law of Battle): It's a struggle between the males for the possession of females. Two males of the same species fight out, and the goal is to drive off the other male in order to win access to females. This kind of selection produces (allows the developpment of) armaments, like stronger weapons, larger body size or anything that helps a male win physical contests.

2) Female choice: This is a choice made by females. They "compare" males to each others and recognize the ones which have the most impressive physical features; for example, females birds prefer males with big tails, bright colors etc. And females frogs prefer males with complex calls. In those cases, the "armaments" that males deploy are different.

=Why sex?

= that's THE key question... and the answer is not so simple...[[Util isateur:Pierre.brawand|Pierre.brawand]] 19 avril 2011 à 22:39 (CEST)

Why choose ? And why is it the role of females?

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