ch. 7 primate behavior
Terms in this set (26)
Why study primates?
because they are social (esp. anthropoids) and we want to to know the pros and cons of groups
primate behavior study conducted in a zoo, laboratory, or other enclosed setting
pro: easy to observe
con: not natural environment, therefore not natural behavior
primate behavior study conducted in the habitat in which the primate naturally lives
pro: natural environment/behavior
con:difficult to observe, you have to habituate them to humans, habituating can also cause them to be vulnerable to hunters
adaptive behavior in baboons
aggressive males have more reproductive success than non-aggressive males, which is somehow a part of genes.
females have a lower reproductive potential than males. (Males compete for females)
the limiting factor for males is the availability of females. limiting factor for females is long gestation/maturation.
primate social system in which females remain and breed in the group of their birth, but males emigrate. this helps prevent incest.
primate social system in which males remain and breed in the group of their birth, but females emigrate.
things that affect primate social systems
distribution of females
number of males in a group
relationship with other members is determined by fighting or dominance hierarchy
being highly ranked provides more access to food/mating
not as important in females, but still exists
parental involvement of males
usually very little male parental involvement
how males determine dominance
usually instead of fighting they have a series of small confrontations/contests
eventually, the males that repeatedly win the confrontation become dominant
not always a rigid hierarchy (sometimes multiple males will gang up on a dominant male and take over)
female reproductive strategies
choose mates carefully
willingness and ability of a female to mate, also defined as fertility
females show sexual receptivity by..
behavioral or anatomical signs (Chimps have sexual swellings..)
paradox of sociality
pro: improves access to mates
uses food finding capabilities of others
increased protection from predators (lookouts & less probability in a group)
con: more male competition
competition for food
more likely to be targeted by predators
the grouping pattern in which a primate species lives, including its size and composition evolved response to natural and sexual selection pressures
spend time alone for the most part other than mating.
Orangutans & prosimians
orangutan social system
the males have territories that are broken up with females in different parts. Males try to maintain exclusive access to females in their territory.
one male and one female mate and live together. for the most part.
female reproductive strategy because the females let the males into their territory so that males can protect and provide food.
advantage for males: likely that the male fathered the offspring, less competition
multiple females live with one or more male
allows for more complex male competition
multiple females live with one male
groups of males that don't have a mate yet
periodically they try to find a mate and take over another male's group
results in infanticide because the new male wants to kill the offspring of the other male.
multi-male, multi-female groups. males have a hard time exclusively mating with females
dominant males have priority of access but not exclusive access.
most dominant male. enjoys the most reproductive success.
most complex social group
travel in foraging parties of varying sizes
temporarily associate with each other
come together and split up a lot, unstable
believed to have evolved from diet of primarily ripe fruit with seasonal distribution. they split up to limit competition for food
spider monkeys, chimps, bonobos
one female mates with multiple males. very rare.
a few species of marmosets and tamarins.
usually a female mates with 2 different males and both have parental presence