lecture 28 Flashcards
Coefficient of relatedness between adopter and adopted child study
large majority of adoptions involve some degree of relatedness; 60% has coefficeint of .25, indicating either the adoption of one’s nieces or nephews, or grandparents adopting their grandchildren
Odds of receiving money for college
odds that a man will give a child money for college is much higher if he is the genetic father rather than the stepfather
Stepchildren and abuse
rate of murders per year was much higher when it involved a stepfather to a child compared to a genetic father; also a much greater amount of abuse for children that have one step-parent compared to children that have two natural parents
Evolution of menopause
reproductive capacity drops off much more rapidly in women than men; decline in reproductive performance is much more drastic compared to other physiological measures that decline much more slowly
Grandmother hypothesis
Menopause is an adaption- it may be beneficial to forgo personal reproduction which becomes more risky with age, and instead aid in the reproduction of close relatives-invest in new descendants in order to increase average lifetime reproductive success
4 assumptions of grandmother hypothesis
- Human children are dependent on mothers for several years after weaning, so woman’s ability to have additional children is limited by need to provide for older children; 2. as women age, probability of living long enough to nurture a baby from birth to independence decreases; 3. as women age, risks associated with pregnancy and childbirth increase; 4. as women age, her own daughters will start to have children
Fitness benefits of having a grandmother around
women whose mothers are alive had higher fecundity and lifetime reproductive success and also earlier age at first reproduction; women whose mothers are alive have shorter birth intervals and their children are more likely to survive to puberty if grandmother is alive and younger than 60; women whose mothers are local have more grandchildren; for every 10 years of postmenopausal life, grandmother gets 2 more grandchildren
Sex chromosome selection hypothesis
grandparents are asymmetrically related to grandchildren based on sex chromosomes, which could lead to differences in grandparental care; for example, grandpa passes Y down to son who passes down to his son
Paternity uncertainty hypothesis
more supported, degree of paternity uncertainty influences grandparental care; a grandmother has zero degrees of uncertainty to granddaughter; grandfather has one degree of uncertainty to his daughter’s children and 2 degrees to his son’s children; grandparental care is highest for maternal grandmothers, then maternal grandfathers, then paternal grandmothers, then paternal grandfathers
X chromosome relatedness between grandmothers and grandchildren
PGM has 50% relatedness of sex chromosomes with granddaughter and 0% with grandson; MGM shares 25% with both grandsons and granddaughters; the higher the X relatedness between grandmother and grandchild, the greatest affect on survivorship of the grandchild; grandsons survived better in presence of MGM compared to PGM; PGMs lead to higher survival in granddaughters than in grandsons who they share 0% X relatedness with
Possible chemical contaminants
agrochemicals, heavy metals, acid rain, chlorofluorocarbons
Agrochemicals
herbicide atrazine has led to egg mortality and tadpole deformities ; these animals can serve as bio-indicators for pollution; example of how behavioral research can be used in context of conservation
Whooping crane
conservation biologists have taken advantage of imprinting behaviors to save whooping crane from extinction; they imprint on humans in crane suits who then lead them in migration through using aircraft
Japanese beetle
they find mates through pheromones so you can use this behavior to produce pheromone traps
