Pathological response to human disturbance high

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Pathological response to human disturbance, high population density Population regulation to avoid starvation Only in high density populations/areas of human disturbance find more resources at oneclass.com find more resources at oneclass.com
Selection shapes behavior that's good for the individual, not the population - so these are wrong Increase male reproductive success Faster reproduction than otherwise If females are nursing, they cannot get pregnant Species with lactational amenorrhea, short male tenure Targeting infants of other males New males, no prior mating with females If the male is familiar with the females, the offspring is his, doesn't kill them High chance of siring the next infants Monopoly - females have no choice but mating Dominant males, one-male groups, male hierarchy Conditions for infanticide Lactation > gestation Have to wean current offspring before giving birth If lactation period long, cannot get pregnant Lactation shorter than gestation - can get pregnant and finish weaning by the time they give birth to the next one - no infanticide Lactation longer than gestation post-partum amenorrhea to avoid overlapping infants - most primates, infanticide Low probability of being father Fathers do not kill the infants Immigrant males, young males High probability of siring future offspring Short tenure as alpha, high mating skew Greater difference between infanticidal/non-infanticidal strategies Long tenure - less infanticide If the conditions for infanticide are met, we should expect it in any species - good theory allows good predictions Doesn't necessarily have to be males, speeding up someone else's reproduction to increase your reproduction Happens in females in some species Males guarding eggs Females kill eggs so males would take care of theirs Female counterstrategies The male that's with them keeps all males away - females can't get rid of them Deceit - mate with the new male to make them think that it could be their infant Mating with multiple males that threaten them - confuse/diffuse paternity by mating promiscuously Prevent new males from immigrating Protect their infant from immigrant males Recruit male protectors if possible If infant is killed, mate with new male Male-female association tracks infanticide risk Female stress levels when there is an infanticidal new male is around, if the female is lactating, are elevated They don't understand this but they feel stressed find more resources at oneclass.com find more resources at oneclass.com
If they have a male protector, the glucocorticoid levels go back to normal Infanticide in humans? Lactation > gestation? Yes, birth spacing in 4 years Low probability of being father - stepfather High probability of siring future offspring Stepfather, if lack of social sanctions Some societies may allow it Infants are 60x more likely to be killed by stepfather than genetic father (baby ages 0-2) The truth about Cinderella - stepparents pose more threat to children find more resources at oneclass.com find more resources at oneclass.com

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