Class Notes (1,100,000)
CA (620,000)
UTSC (30,000)
Lecture

BGYB51H3 Lecture 21 Notes Nov 19


Department
Biological Sciences
Course Code
BIOC51H3
Professor
Maydianne Andrade

This preview shows half of the first page. to view the full 1 pages of the document.
BGYB51H3 Lecture 21 Notes
-females are the agents of selection in intrasexual selection
-females increase their fitness through direct or indirect benefits
-sperm transfer ends after 20 minutes of copulation even if female is still eating prey, males
take prey from female after 20 minutes
-genetic quality involves males having heritable traits that can give higher fitness for offspring
-experimental manipulation eliminates confounding variables that might mask possible sexual
selection
-females prefer males with the most elaborated ornaments
-cross-fostering offspring involves assuming equal environmental effects between offspring in
order to determine their heritability
-offspring with more elaborated ornaments have better genetic quality than other less
ornamented offspring
-males have much traits that are not connected to good genes that provide survival or
predator/parasite resistance
-sexy sons hypothesis is that certain traits give higher mating success for sons of females; not
indicators of genetic quality
-no survival benefits with traits that are not connected to good genes
-benefit of choosing male with trait only occurs if a large number of other females also prefer
this trait
-preferences in females may already exist as innate in their sensory system (sensory bias
hypothesis)
-certain arbitrary stimuli can cause female responsiveness because of innate sensory system
-competition and choice act together in many populations to cause both direct and indirect
benefits together
-sex role reversal involves male parental care or large nutrient gift increasing parental
investment
-sex role reversal involves male having a higher parental investment than females; females
compete while males are choosy
-variation in number of mating in females and less variation in males in sex role reversal
-basic differences in parental investment affect sex roles rather than sex roles depending on
maleness or femaleness
www.notesolution.com
You're Reading a Preview

Unlock to view full version