Sexual Selection

• Sexual selection is the process by which individuals with traits that increase their reproductive success are more likely to survive and reproduce
• Anisogamy is differences between male and female sex cells - one explaination for different partner preference.
• Describe Anisogamy in Women

  Eggs take a lot of energy to produce, are created in limited numbers during specific time intervals and their production only lasts for a certain number of fertile years. This led to the theory of Inter-sexual selection.
• Intra-sexual selection is the competition between men and somtimes women for mates.
• Describe Anisogamy in men.

  Sperm is produced in large quantities, quickly replenished and created continuously from puberty to old age. Optimal strategy is to with and impregnate as many humans as possible.
• Intrasexual selection can also have controversial behavioural and psychological effects.

  • physical dimorphism - size matters
  • Males and females of a species often look very different.
  • Can also cause agression, possessiveness and protection.
• Intersexual selection is the prefered strategy of females that suggests the optimum strategy is to select a genetically fit partner who is able and willing to provide resources.