III. Sex and SelectionA.Costs and Benefits (notes)
III. Sex and SelectionA.Costs and Benefits (notes)B.Sexual Selection - selective pressures may differ between the sexes, resulting in selection for different physiologies, morphologies, and behaviors.1.Mating Systems: - should you have many mates or one mate?
# mates
# of
fspr
ing
male
female
NEWTS
Jones (2002)
III. Sex and SelectionA.Costs and Benefits (notes)B.Sexual Selection - selective pressures may differ between the sexes, resulting in selection for different physiologies, morphologies, and behaviors.1.Mating Systems: - should you have many mates or one mate?
# mates
# of
fspr
ing
male
female
PIPEFISH
Jones (2002)
III. Sex and SelectionA.Costs and Benefits (notes)B.Sexual Selection - selective pressures may differ between the sexes, resulting in selection for different physiologies, morphologies, and behaviors.1.Mating Systems:2. Intrasexual Selection – where competition within a sex occurs
Sexual Selection
2. INTRAsexual Competition - competition for harems, territories
Sexual Selection
2. INTRAsexual Competition - competition for harems, territories - sperm competition
Sexual Selection
2. INTRAsexual Competition - competition for harems, territories - sperm competition - infanticide
Sexual Selection
2. INTRAsexual Competition - competition for harems, territories - sperm competition - infanticide - female mimicry in male subadults and "stealth matings"
"sneaker males"
FEMALE
"Sneaker" male
Sexual Selection
3. INTERsexual Selection (Mate Preference) - A behavior or morphology that is only performed during the
reproductive season, which increases risk and must then be offset by mating
Sexual Selection
3. INTERsexual Selection (Mate Preference) - A behavior or morphology that is only performed during the
reproductive season, which increases risk and must then be offset by mating
showy breeding plumagecalling displays
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit - parental care
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit - nuptual gifts (energy for egg making)
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes - ‘Handicap Theory’
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes - ‘Parasite Load Theory’
Hmmm....
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes - ‘Symmetry Theory’
Hmmm....
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes - ‘Symmetry theory’
Hmmm....
Hey, It Works!!
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes - ‘Symmetry Theory’
3. INTERsexual Selection (Mate Preference)- WHY is it ADAPTIVE for the FEMALE to choose a given male??
1. Direct Benefit2. Indirect Benefit: Good Genes3. Runaway Selection