Aggression Flashcards
benefits of having a high rank for female competition/cooperation
Benefits of high rank: Better access to food Better feeding efficiency since they get interrupted less Receive more grooming Get harassed less More likely to receive agonistic support
how high rank has positive effects for female reproduction in geladas
Robin Dunbar studied Gelada baboons and compared rank to matriline size. Found that a large matriline meant higher rank. Higher rank means less harassment, which means less energy wasted fighting. Thus, higher rank increases the number of offspring that an individual has.
how high rank has a positive effect on female mortality in verbet monkeys
Richard Wrangham studied vervets. It was a severe drought. Vervets always sleep in trees at night, and some of the trees are closer to the rare water than others. Because it was such a drought, it became important to survival how close your tree was to the water, and he found that the higher-ranking individuals got the trees closer to the water.
During this drought, more lower-ranking vervets died than higher-ranking; Three out of four higher ranking survived, while only one out of four lower-ranking survived.
how high rank has a positive effect on Female Fertility
Fertility has been linked to higher rank in vervets, macaques, and mustached tamarins, to name a few. In all of these, high-ranking females gave birth more than low-ranking females.
What proximate factors affect patterns of female competition and cooperation?
Kinship: Kin engage in serious aggression less often than non-kin. Also, a substantial portion of cooperative acts are performed between kin.
Rank: High ranking females are more attractive social
partners.
Reproductive state: Lactating females are attractive social partners for both immature and adult females- they receive a lot more grooming than when they’re not lactating. This is probably mostly because the others are trying to get close to the newborn so they’re being nice to the mom.
Also, sexually receptive females receive more grooming and give less, and are also more likely to receive agonistic support from males against other females.
Immigration status: Resident females harass and attack immigrant females in both gorillas and chimps, for example.
gelada vs hamadryans baboon
The gelada baboon:
is a typical old world monkey in that males disperse and females stay.
In these groups, the male is supposed to be the central guy, but he doesn’t have a lot of strong social bonds with the females, who all like each other and groom each other frequently. If the male disappears, the females will usually stay together.
In hamadryas baboons, females disperse and so they have weak bonds with each other.
Most of the strong social bonds in the group are between the male and his females. If the male disappears, the whole group will usually disintegrate.
So while their social organization is pretty much the same, because the dispersal pattern is different, their kinship and social stuff are different.
classic instinct theory
all organisms are born with innate biological tendencies that help them survive. This theory suggests that instincts drive all behaviors.
hence aggression is an ‘instinct’
history of nature : culture developments
- nature: culture dichotomy
2, judeocrhstianism (cain and able; agrictulrusts vs pastoralists/ adam and eve bring sin to world)
- hobbes: nature pessimisim
- roussea; culture pessisms
- goodall; nature optimisim
- lorenz/ebelsfeld; nature optism and group selection
issues with lorenzian aggression
- not supoported by evidence
- aggresion is REACTIVE not spontenanous
- infanticide occurs among non-human animals
- killing of adult consepecifs also occurs among non0human animals like chimps
baby schema
cute babies are protected from aggression due to their cuteness (bigger eyes, bulging craniu,)
hydraulic model
elaborates instinct theory; aggression is the endogenous production of DRIVE-specific eneryg build up that is released by AUTOMATISM
evidence for infanticide/intergroup warefare (2 primatologists)
sara hrdy; infanticide in langurs in abu
jane goodall; the chimps of gombe and intergroup ware fare
role of the olympics/games
ritualized aggression techniques to promote peace
cute traits in babies
large eyes
retreating chins
bulging cranium
non-cute traits in adults
small eyes
long snouts
prominent chins
issues with baby scheme idea
(infanticide; babies are still killed)
