The Bacculum Flashcards
What is the Bacculum
a bone at the distal end of a primate
where is the bacullum not present
nw world monkeys
tarsiers
humans
vaginal friction hypothesis
bacculum functions as a ‘shoe horn’ to squeeze penis into females where there might be resistance (i.e. in sexuall dimorphic species like hyenas)
induced ovulation hypothesis
bacullum stimulates ovulation in females (cats and rodentss)
prolonged intermission hypothesis
facilitates longer copulation and cock blocks other males
how does the bacculum help
mechanistic support (strength) for prolonged sex and success (i.e. polygyandrous or seasonal breeders might have it)
why do humans not have a baccylum
–> handicap principle/selfish genes; a costly signal that female cryptic choice selects for
- in monoandries; less post-copulatory competition and shorter copulation
what are the hypothesis about why some species have a bacculum and others dont
induced ovulation hypothesis
vaginal friction hypothesis
prolonged intermission hypothesis
