Evolution Flashcards
What is a gene ?
Unit of heredity that contains DNA carrying info from one generation to another
How does each gene influence development ?
Triggers production of enzymes & proteins involved in production of certain cells
What is a genotype ?
Genetic makeup of someone
What is a phenotype ?
What the individual becomes when genes interact with each other & environment
What is a dominant gene ?
Genes always leading to certain characteristic
What is a recessive gene ?
Gene needing more than one copy to produce a characteristic
What is evolution ?
How inherited characteristics in organisms change from generation to generation
What is fitness ?
Measure of an animal’s ability to pass on its genes, in terms of the number of viable offsprings that arise
What is adaptation ?
Physical feature of behaviour said to be adapted to environment in that it has been tested for suitability to that environment
What did Buss et al suggest ?
Those that provide best fit for environment survive & pass genes on
What is a mutation ?
Change in genetic structure of an animal/plant that makes it different from others of same kind
What is sexual selection ?
Form of natural selection : individuals that are successful in attracting a mate out-reproduce others in that population
What is genetic drift ?
each male & female pass on 50% of their genes, not 100%, element of chance in which genes are passed on and which aren’t
What are heritable traits ?
Characteristics have genetic tendency combined with experiences in the environment, not all heritable
What is natural selection ?
Survival of the fittest, characteristics not aiding survival die out as organism wouldn’t survive to reproduce
What is kin selection ?
Natural where natural disadvantageous characteristics increase in population due to increased survival of individuals genetically related to those holding characteristic
What is direct fitness ?
Gene gives characteristics to benefit survival
What is indirect fitness ?
Disadvantageous characteristics to individual but advantageous to relatives
What is group selection ?
Ability to survive more readily if part of group
What is anisogamy ?
Where males produce many sperm at low psychological cost whereas females produce few eggs at high psychological cost
How are males in the environment of evolutionary adaptedness ?
Successful ones physically bigger & stronger = more capable of providing food and protecting
Why are successful males at an advantage ?
More likely to gain attention from female mates
What has competition for mates given ?
Masculine aggression
Why are females less aggressive and more emotional ?
Aggression is evolutionary disadvantage = pregnancy and puts children at risk
What would we expect to see if ideas on female and male aggression is true ?
Differing brain structures
What is Fisher’s hypothesis ?
Females are attracted to males with survival value
Supporting research (reproductive behaviour) = Buss
- Cross cultural study show men & women in 37 cultures follow patterns of behaviour predicted by evolutionary theory
- Females valued good financial prospects, older males
- 36/37 = males valued physical attractiveness, younger females
Opposing research (reproductive behaviour) = Buss
- Evolution largely discounts cultural differences
- Significant cultural differences = mate preference differed (Western & non-Western)
Supporting research (reproductive behaviour) = Davis
- Content of personal ads in newspapers
- Women looking for mate = emphasis on physical beauty (looking for high status)
- Men = emphasis on wealth (looking for youthful woman)
Reductionist/holistic ?
- Reductionist = suggest behaviours are part of dispositional factors, ignores situational factors
- May be attracted to individuals we are exposed to/more contact with
Explanation for aggression (jealousy) ?
Compete for mate to pass on genes
What is jealousy ?
Biological disposition
Why are males jealous ?
Suspecting female was unfaithful, females = parental certainty
Why are females jealous ?
If there is another woman
Criticism = jealousy
Females aggressive jealousy may deter another woman, how much jealousy turns into aggressive action depends on social norms, personalities & strength
Explanation for aggression (limited resources) ?
Fighting for resources, defending food & shelter for survival live & reproduce, behaviour then inherited through genes
Supporting research = Dunbar, Barrett & Lycett
- Replicated Buss across cultures, investigated private beliefs & behaviours while complying with modern ethical views
- Research already in public domain, more truthful
What is male aggression ?
- Motivated to acquire status, high status = access to mates & resources
- Not engaging in conflict may be costly
What do low status males have to do ?
Engage in high risk strategies to enhance changes in reproduction
Supporting research (male aggression) = Daley & Wilson
- Review of murders found motive behind conflict = status, most victims & offenders low status & without mate
- Most knew each other = understood status of rival
- Equal status = more likely to be aggressive to move status above opponent
What is female aggression ?
Less aggressive (costs of behaviour outweigh benefits), more important to survive
Supporting research (female aggression) = Hill & Hurtado
- Ache of Paraguay, children 5x more likely to die if moths dies
- 100% if happens before child is 1
