Buss, Chapter 7

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Buss, Chapter 7
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Cost/benefits of parenting

• Costsresources opportunity cost (i.e., could
  be increasing fitness with other mates) could
  use resources for self risk
• Benefitsincrease chances children will live
  reproduce (e.g., protection from predators,
  provide resources)

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Why mothersgtfathers in parenting?
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Paternity uncertainty hypothesis

• More paternity uncertainty with internal
  fertilization
• Fathers should be less likely to care for
  offspring that might not be theirs mothers
  usually certain

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Abandonability hypothesis

• Whichever mate can first abandon offspring more
  likely to do so
• Usually males
• More often females with external fertilization
  (e.g., some fish), and then males do more
  parenting (but paternity certainty greater in
  external fertilization also)

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Mating opportunity cost hypothesis

• Reproductive rate faster reproducers (males)
  can use time/energy to increase fitness more by
  mating with others instead of caring for young
• Context effects male/female ratioswhen plenty
  of females per male, less parental care by males
  and vice versa

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Parental favoritism

• Some children should be (from an evolutionary
  perspective) favored over othersthose who will
  pay off with increased fitness for parents
  efforts
• Parents feel behave differently toward genetic
  than adopted children (on average)rated
  feelings, abuse, infanticide

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Parental favoritism

• The baby looks just like fathermuch more common
  statement by mothers and relatives than similar
  comment about mothersattempt to reduce fathers
  paternity uncertainty (actual ratings show babies
  dont really look more like father)
• Men more willing to invest in child who looks
  more like them, and treat mother of such a child
  better

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Parents investments in children

• Men allocate more resources to genetic children
  than to stepchildren
• More paternity certainty associated with more
  investment
• Men invest more in child if childs mother is
  their current mate (may be a mating effort more
  than a parenting effort)

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Daly Wilson
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Daly Wilson
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Daly Wilson
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Daly Wilson
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Daly Wilson

• Note that older children abused less they have
  higher reproductive value, as not all infants
  will live to that age
• Also, in modern environment older children are in
  school more mandated reporting of abuse
• Children who are not healthy, have
  disabilitiestend to be abused more

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Women parenting mechanisms

• Mothers hold infants much more than fathers
• High percentage of single parents are women
• Pupillary response greater for women when viewing
  babies, especially babies being held by a mother
• Women better at identifying babys emotions by
  facial expression

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Female-male differences

• Low status men do more caretaking than high
  status men
• Men interact with single mothers child partly as
  a mating strategy they interact less with child
  after marriage

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Parent-offspring conflict

• You share 100 of genes to yourself 50 to
  parents or your children

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Parent-offspring conflict

• Parent should want children to share equally if
  share equal of genes with all children
• Children should be selfish (100 to self 50 to
  siblings)
• Thus, some conflict is between parents goals and
  siblings goals

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Parent offspring conflict

• Parents genes vs. childrens geneseach have
  selfish motives
• Prenatallywhat is best for baby not always best
  for mother e.g., fetal hormones to increase food
  supply can cause high blood pressure in mother