1
Q
phenotype
A
- actual, observable, measurable, documentable traits of an individual
- always dependent on genotype and the environment
- e.g. having a genetic predisposition that interacts with the environment to produce the ultimate phenotype
2
Q
genotype
A
- sum totally of all genetic material and individual contains
- individual genotype; what you have in your DNA
- can be changed or modified
3
Q
heritability
A
never what is present or observable in an individual, ONLY making attributions of the cause of a trait in a population
4
Q
discrete traits
A
- involves either a single gene or at least a very small number
- relatively discrete traits means you have few versions of the trait
- something that involves a single gene or version of the gene, if its beneficial will increase in the population quickly b/c it is easier to select for or against
- may evolve faster and can be difficult to get rid of single gene effects
5
Q
heterozygous
A
an individual having two different versions; one from each parent
6
Q
homozygous
A
same version from each of your parents
7
Q
sickle cell - homozygous
A
- people who are homozygous will only have pounded red blood cells (good)
8
Q
sickle cell - heterozygous
A
- people who are heterozygous don’t have sickle cell disease
- will only occur in heterozygous individuals when circumstances don’t allow for red blood cells to properly function i.e. high altitudes
- heterozygous for sickle cell will produce both forms of blood cells meaning they will have “sickled” red blood cells and regular red blood cells
9
Q
2 versions of sickle cell coding
A
- only have sickle red blood cells
- consequences for transportation and absorption of things through the blood stream
- two different versions and being heterozygous for the conditions can be totally fine without environmental impacts
10
Q
carriers of sickle cell
A
people who are carriers for this trait will likely have offspring with the same chances of being perfectly fine, a carrier or effected
11
Q
sickle cell and malaria
A
- where this trait is common, malaria is also a risk
- people with sickle cell trait can be resistant to the effects of malaria and are far less likely to die
- the trait persists because the benefit is greater than the cost
12
Q
heterozygote superiority
A
- refers to the advantage that the heterozygous condition has in an environment where there are strong risks of being either version of the homozygous conditions
- e.g. in an environment with malaria, the sickle cell trait may be more common
- e.g. disorders that target males because they don’t have backup if there is a mutation on the x chromosome
13
Q
polygenic traits
A
- characteristics influenced by two or more genes working together, rather than a single gene
- can also be subject to environmental impact
- if the trait is valuable there will be rapid selection for it, but it will still have variability if lots of genes are involved
- many human traits are assumed to be polygenic b/c we see a distribution of the trait that makes us think it is not discrete and probably controlled by multiple genes and environmental contributions
14
Q
intelligence - polygenic traits
A
- some genes have been identified as related to intelligence but it remains very unclear
- every single genes identified thus far, you can find it in people with relatively low IQ
15
Q
social traits - polygenic traits
A
- extraversion and genes associated for it also code for things like the production of cortisol and epinephrine
- then you must consider how the environment interacts with that coding
16
Q
variance in species
A
- trait neutrality
- environmental variation
- heterozygote superiority
- frequency dependent selection
- sexual reproduction
- facultative adaptation
17
Q
trait neutrality
A
- don’t have a positive or a negative impact on the population
- might vary in a population because it doesn’t matter
- no strong selective pressures = free to vary
18
Q
environmental variation
A
- variability as different populations have settled into different niches across the planet
- e.g. darker skin and eyes if you have ancestors from Ecuadorian regions; light skin and light eyes if ancestors are from farther north regions
- we also inhabit environments that change across seasons
19
Q
frequency dependent selection
A
- a trait is maintained in the population at a particular level in which the population can support
- we see variability within a trait because something is only valuable when it is rare
- occurs at the population level
20
Q
frequency dependent selection - example
A
- individuals with a psychopathic personality can have traits consistent with being potentially dangerous or harmful (lack remorse, aren’t affected by others emotions/lack empathy, spot when they can benefit from someone else)
- if 80% of our population had these traits → we wouldn’t be particularly helpful or nice and would likely be very skeptical and less trusting
- being a psychopath can be very adaptive → get a lot o resources → out compete people in many situations →likely a lot of reproductive opportunities
- however being a psychopath is only “adaptive” because it is rare and make up no more than 5% of the population → highly adaptive traits but if they are too common these traits stop being adaptive
- skills and traits are less effective when they are more common
21
Q
sexual reproduction
A
- always creating a new version of the species
- e.g. kids are clones of their parents they have variability
22
Q
facultative adaptation
A
- facultative means on demand or responsive
- a trait that can shift depending on demand is flexible
- respond more appropriately to environmental changes that can occur a lot, not only immediate changes but future situations
- e.g. an adaptation that is only expressed in certain conditions or a genotype that says if all these things happen, this trait will be expressed. Or a gradual shift with repeated exposure
- e.g. not a lot of food = reign in metabolism
23
Q
epigenetic landscape
A
- new knowledge with interactions in the environment
- where you end up will depend on how you started and where you started as well as what happened on the way
- some trajectories are changeable, some are not but it is dependent on when the change happens
- e.g. you have a kid with an average level of extraversion; can be shaped dramatically into more of an extravert or into an introvert based on what happens through their life
Once you trajectory has been set (once you are a child) it is difficult to shove a trait in the opposite direction
24
Q
environmental volatility
A
- change in environmental conditions
- flexible adaptations that are responsive to changes in the environment
- e.g. humans have a shift in metabolism associated with the ambient temperature
- having a physiology that is responsive to environmental encounters is very useful
25
migration
- humans like the move around
- having a physiology that is responsive to environmental encounters is very useful
26
long lives
- humans live for a long time
- on average humans have one of the longest life spans
- this causes us to encounter a lot of different environments which could be due to environmental shifts, live through different seasons, etc
27
why are some adaptations facultative rather than fixed?
1. environmental volatility
2. migration
3. long lives
28
flavour preferences
- olfactory bulb and gustatory cortex are densely interconnected with our limbic system and hippocampus
- we can intense emotions or triggers from flavours or odours
- tied to the environments we live in
- mechanisms associated with developing preferences for flavours
29
single trial taste aversion learning
if you get really sick you with attribute it to not the most familiar food but to anything novel or salient that may have been art of a meal
30
mechanisms associated with developing preferences for flavours
1. social learning
2. local availability
3. ultimate explanation
31
social earning and flavour preferences
- presence of certain foods, associated with family, rituals, celebration or are prepared for you, on average become preferred flavours within the cultures they are associated with
- variety across cultures based on foods most preferred, delicacies or appropriate for celebration
- involved physiological components; familiarity, tolerance, or greater preference for a flavour
- direct chemical familiarity that builds up
- common in mammals, less common in other animal groups
- children are more likely to eat foods they see adults reaching for
32
flavour preferences in pregnant women study
- test infants after birth for flavour preferences based on the controlled food the mother ate
- sample of women who rarely if ever ate carrots
- one group continued not eating carrots the other would eat a small serving every day
- did this for the last sick weeks of pregnancy
- when the infants were four months old and offered them mashed carrots for the first time and they recorded facial expression and how much was actually consumed
- the ones whose mothers ate carrots, after initial caution accepted mashed carrots and ate a larger volume with minimal negative facial expressions; some were even eager to eat the carrots
- the groups whose mothers didn't eat carrots only had one baby that was enthusiastic the rest were very unsure, displayed many negative facial expressions and consumed very little if any
33
local availability and flavour preferences
- tied to the environments we live in
- related to food safety
- cultural related: kosher and halal food laws → directly related to what is least likely to make people sick or have ritualistic purpose
- making things last longer: packing things with salt, turning dairy to cheese, pickling
34
ultimate explanation and flavour preferences
eating things less likely to kill you which involved both how we modify our foods and how we learn what to eat
35
transition from independence to parenthood
- offspring are altricial meaning they are incapable of surviving on their own
- e.g. infants can lift their heads up because their heads are too big and their brain continues to grow and expand with time
- parents need adaptations that make them want to take care of infants
- pregnancy in an ancestral environment may have been less thought out, planned and intentional so our current adaptions may be different
36
perceptual preferences/biases for faces
- babies faces appear to be something elicits an ‘aw’ reaction form the majority of people
- perceive people with bay faces as younger, dumber, and trustworthy
- more likely to be gentle with people with these faces
- applicable to animals → nicer to puppies or kittens vs. dogs and cats
37
baby talk or ‘motherse’
- change speech when talking to an infant
- higher pitch
- ‘feminine’ tone
- repeat words
- random nonsensical noises
38
oxytocin in pregnancy
- associated with digestion, but in the context of pregnancy
- it triggers the onset of contractions, and processes associated with initiating lactation
- after birth oxytocin levels stay high and are associated with strengthening the bond between mother and infant
- Skin-to-skin contact increase oxytocin levels drastically and is also associated with a corresponding decrease in testosterone levels
39
PTSD
- occurs after someone has experienced a trauma
- typically reasonably perceive their life or the life of someone they care about is in danger
- early research was done on war veterans (shell shock, battle fatigue)
- symptoms vary depending on trauma experienced
40
common PTSD symptoms
1. hyper-vigilance and more prone to startle
2. flashbacks - intrusive and immersive
3. difficulty falling asleep or staying asleep
4. faster reaction times and startle responses
41
individual differences in PSTD
1. personality impacts a person's likelihood of developing PTSD
- neuroticism → more prone to anxiety in general the higher the likelihood of developing PTSD
2. prior experience
- people who have had many difficult experiences may have built up resilience to new traumatic situations
42
PTSD symptoms and resilience
- resilience doesn't mean the trauma isn’t more you can handle b/c there is a correlation between a less strong effect not that high resilience prevents PTSD
- PTSD symptoms are good for surviving if the threat comes back
- e.g. domestic violence situations
- symptoms are only problematic when the danger is gone
- evolution doesn't select for what you want to happen or what makes you happy and facultative adaptations can't be turned on and off
43
occurrence of PTSD
- the disordered behaviour results from the environment not matching up to the adaptation anymore
- triggered under extreme circumstances
- PTSD can be seen as an adaptive response based on what someone has been through
psych 373: evolution & human behaviour
flashcards
Decks in class (9)
# Cards
