WEIT Chap6

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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)

Introduction

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 a female


why only ONE female... Generally, males fight for more than ONE female... in order to be sure to transfer their alleles in the offspringPierre.brawand 19 avril 2011 à 22:36 (CEST) . 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.

2) Female choice: This is a choice made by females. They "compare" males to each others and recognize the most beautiful


beautiful is not the right term herePierre.brawand 19 avril 2011 à 22:38 (CEST)

and the biggest physical features (like a big tail, bright colors, etc.). The choice is done after that comparison, and many experiences 

EXPERIMENTSPierre.brawand 19 avril 2011 à 22:38 (CEST)

showed that the strongest and most beautiful 

again not the right term animal were chosen by females.

How does it work?

Why sex?

What is dimorphism?

A question of choice?


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