Sexual Selection

Question 1

Sexual selection

Answer 1

• Darwin recognized that sexual organisms not only need t survive and reproduce
  
  • Also need to find a mate with whom to reproduce
• Failing to find a mate is the same as dying young
• Sexual selection is differential reproductive success due too variation in success at getting mates

Question 2

Males

Answer 2

• Sexual selection is usually stronger on males:
  
  • Reproductive investment
  • Operational Sex Ratio
• Intrasexual Selection (Male-male competition)
• Males are competitive

Question 3

OSR

Answer 3

The ratio of male to female individuals who are available for reproducing at a given time

Question 4

Intrasexual Selection
(Male - male competition)

Answer 4

• Males compete with each other for access to females
• Combat: size, weaponry etc
• Sperm competition
  
  • Lots of motile sperms
  • Mate guarding, mating plugs, sperm extraction
• Infanticide

Question 5

Intrasexual Selection
(Female choice)

Question 6

Females

Answer 6

• Females are choosy