set 9

Question 1

being a step-child

Answer 1

• disproportionate risk associated with being a step-child or non-bio child
• e.g. “beaten by a red-headed step-child” saying

Question 2

kin selection

Answer 2

• it is adaptive to provide disproportionate help to genetic relatives
• including all of the ways your genes get into the next generation → inclusive fitness
• supporting an identical twins reproduction is just as good as having kids yourself
• half sibling would fall in with the cousin category
• you should be investing more into the individuals most closely related to you compared to those least related to you

Question 3

nepotism

Answer 3

• being related to someone is a form of privilege that allows you to get access to resources, connections and an overall leg up
• we find that although proportions may differ, the pattern indicates that individuals with the highest incomes have a stronger correlations between employment of fathers and sons
• nepotism is an example of kin selection working
• favouring someone you are related to over those you aren’t

Question 4

parental investment and females

Answer 4

• weighing current investment options (are they worthwhile) or would you be better off investing in future investment options
• female contemplating casual sex b/c there is a trade-off with getting pregnant now since it blocks potential reproductive opportunities in the future
• explains why females are more cautious or choosy when it comes to casual sex
• current investment impacts or reduces future investment
• mothers with a longer reproductive window in front of them are more likely to commit infanticide

Question 5

areas of conflict

Answer 5

• individuals with different goals sets of the possibility for conflict
  1. birth weight
  2. weaning
  3. amount of resource investment

Question 6

birth weight and conflict

Answer 6

• there are genes that differ in the sperm and egg that influence birth weight of offspring
• women would prefer smaller infants and males would prefer larger
• not tested experimentally in humans yet but you can go in and do gene knockout studies where you selectively turn off the coding associated with different alleles
  - e.g. if you turn off the coding associated with the sperm your offspring will be smaller sometimes dangerously smaller and vice versa if you turned off the egg coding
• when you have competition between both the sperm and egg alleles, you have the stabilizing effect
• equal genetic relatedness to the offspring that have a push or pull for the birth weight trait

Question 7

weaning and conflict

Answer 7

• production and quality of milk changes and can be regulated based on the feedback from infant saliva
• an infant who feeds for longer, will begin to change the composition of the milk
• the goals between mother and offspring will be identical, with focus on survival and fitness of both
• once the offspring reaches the point of being able to eat solid food and it is no longer a matter of absolute survival, there will be motivation on behalf of the mother to stop breastfeeding
• the longer you nurse for the lower your likelihood is of getting pregnant, so stopping caloric investment will allow for you to have another offspring

Question 8

amount of resource investment and conflict

Answer 8

• conflict can be between reproductive partners, parent and child or child and child
• many reasons why parents provide different amount of resources to different children like, age, sex/gender, resources availability etc
• this different amount of investment will lead to conflict between the children
• e.g. how much are you going to investment in my kid; your kids; our kids
• some of the conflict is biological and not conscious whereas some could be very conscious and deliberate
  - eg. a conscious decision would be when determining a will

Question 9

lions example

Answer 9

• lioness do the hunting and protecting, whereas the lions do a lot of sitting around
• lions end up spending more time with the cubs, which makes them incredibly tolerant to these behaviours
• however, if these offspring are not the lions, they will kill them
  - males will defend their pride so heavily because if a new male takes over, they will kill every nursing cub, since they are not theirs
  - juvenile males will also be received as a theta and will likely be killed

Question 10

female jacanas example

Answer 10

• Lecking species → where one individual protects the territory and others will be selective about the individuals with the best territories or largest territories, etc
• Jacanas there is a flipped expectation where the females defend the territory and lay her eggs in multiple nests in the territory and then the males take care of the nests, raise the and offspring
  - mate with males in the territory
  - males will not know if the offspring they are caring for are biologically theirs
• similarly to lions, if another female comes in, the first thing she will do is poke holes in all the ests and eliminate the reproductive output of the previous female
• she will now mate with all the males and lay her eggs in the nest

Question 11

“The Stepchilds Bottom Wiper” - Polygonum senticosum

Answer 11

• the name of a plant with spikes all over it
• idea that being a step-child is a bad deal

Question 12

step-fathers

Answer 12

• step-fathers are a must greater risk to children compared to step-mothers
• yet the stories are always focused on step-mothers, why?
• are they warning their kid about what could happen if they are replaced?
• there is lots of opportunity for step-parenting on both sides, but the risk of step-mothers is pushed a lot more

Question 13

discriminative parental solicitude

Answer 13

• disproportionate care and resources associated with children with higher value and a potential for reduction of this care and resources for children with lower value
• good-looking children may get more attention from their parents
• you do typically find that children who are rated as being more physically attractive and as more “smiling” tend to get more minutes of attention and engagement from their caregivers

Question 14

good-looking children study

Answer 14

• used cameras in a grocery store to rate the attractiveness of children
• found that the children with the lowest levels of attractiveness, had parents more likely to walk away from the grocery cart, leaving the children unattended

Question 15

is murder adaptive to humans

Answer 15

• is the murder or disposal of children, particularly stepchildren, adaptive?
• in the human species, no it is not
• we are a species with a high rate of step-parenting, allo-parenting care, that adopts regularly, raising children not related to us
• we are a social species that on average, takes care of children, making killing children not adaptive

Question 16

why do we use murder statistics

Answer 16

• murder statistics are concrete
• abuse and neglect are often hidden, but murder rarely is
• the adaptation is ‘differential parental solicitude’ but the indirect measure is death

Question 17

murder by biological parent

Answer 17

• highest risk is to children when they are younger and decreases when they get older
• in infancy it is the mother that is most likely to be the perpetrator
• rates are still high among fathers in the first year, but remains high into teen years

Question 18

murder by step-parent

Answer 18

• in the 0-2 age range the risk is 600x higher in step-parent families
• this risk gets lower in the teenage years and the drop-off is argued to be due to avoidance that teenagers adapt in stressful household, and that the longer you’ve had a relationship with the child, the more unlikely you are to harm them
• risk the step-children is more commonly form male step-parents and cause serious injuries or fatalities

Question 19

overall child homicide rates

Answer 19

• homicides per million children, by non-relatives, increases with age, unlike familial homicide rates
• the greatest risk the children if they were to be killed by someone outside the household, exists when they are teenagers
• outside the household is more rare than parents killing children until they are teenagers

Question 20

Australian sample of data

Answer 20

• looked at violent and accidental death
• identified accidental death as due to reduced supervision or care
• ask the question: is the risk of a step-parent, because you have only one bio-parent in the household taking care of you or that the addition of a step-parent is an added risk?
• not only is the risk of violence significantly higher when there is a step-parent but there is also an increased risk of accidental death
• also found children in households with no bio-parents had an increase risk of violence and accidental death compared to both single parent and step-parent homes

Question 21

mortality rates in alberta

Answer 21

• rate that children die from all causes (illness, accidents, violence, etc)
• infants aged 0-2: 1.6/ 1000
• children ages 2-18: 0.1/ 1000

Question 22

mortality rates for alberta children in foster care

Answer 22

• rate that children die from all causes (illness, accidents, violence, etc)
• infants aged 0-2: 4.8/1000
• children aged 2-18: 1/1000

Question 23

Ache of Paraguay

Answer 23

• live a relatively traditional hunter, gatherer lifestyle, with little to no access to western resources in general
• high rate of child mortality which is normally due to infections or consequences of high parasite loads
• 19% die before their 15th birthday → limited reproduction
• 43% with a step-father die before they turn 15
  Slightly greater risk for boys than girls
• mortality was not associated with violence on behalf of the step-fathers

Question 24

child abuse rates in Ontario

Answer 24

• a lot of child abuse is misattributed or hidden so the data consists of children who had to go to an emergency room and the doctors suspected abuse
• rate of suspected child abuse that needed medical care among children in intact biological families was 1/3000
• the rate in step-parent families was 1/75

Question 25

child abuse rates in Korea

Answer 25

- a South Korean study used children that showed up to school with evidence of beating - 40% of children with a step-parent showed up at least once per year with evidence of a beating compared to 7% in a biological household

Question 26

serious victim injury including only broken bones or possible internal injuries in step children

Answer 26

- children in step-parent families are less likely to have routine doctors visits - less likely to have a family doctor or regular health care clinic - less likely to wear seatbelts - less likely to have healthcare coverage - having an unmarried partner in the household creates risk - younger children are at greater risk - females have a lower risk

Question 27

percentage of males and females who picked their self-morph in response to the different questions

Answer 27

- looked at photos of babies and young children and answer questions - the greater the child looked like you, the more likely they will want to invest in them - this study had a massive effect on male participants - possible that one of the proximate mechanism for this effect is resemblance - some children might be preferred over others → discriminate parental solitude

Question 28

adoptive homes

Answer 28

- modern, western adoption is a heavily screened, intentional process - children in adaptive families have the highest rates of health and safety - even better than in a biological household - lowest risk of accidental death or violence