2 - Evolution Flashcards
What are adaptations
biological traits that help an individual to survive and reproduce in its habitat
- perform a specific function
What is natural selection
functional traits (hands, eyes, ears) that helped our ancestors survive
- differential survival and reproduction of organisms AAR of the hertiable differences b/w them
What are the essential components of natural selection
- individual differences
- differential reproduction (some have more offspirng)
- heritability (characteristics passed down)
What is stabilizing selection
selection against any sort of departure form the species-typical adaptive design
What is darwinian fitness
average reproductive success of a genotype relative to alternative genotypes
What is evolution
change in gene frequencies over generations, in part due to the introduction of new gene variants via mutations
What is sexual selection
characteristics that make us look like good mates (become less survivable, increasing mating)
- components of natural selection act on traits that influence an organisms ability to obtain a mate, resulting in differential reproductive success
What is inter-sexual selection
female choice (display feature)
What is intra-sexual selection
male competition (weapon)
What is mate choice preference
female picks males with best resistance to diseases
best genes for being healthy
What are species typical behaviours
movement (topography)
habitat preference
group size
social system
What are behavioural genetics studies
confirm evolution of behavioural traits
- use animals with short life spans = drophila (fruit fly)
What are the types of social behaviours
cooperation ( + + )
alturism ( + - )
selfish ( - + )
spite ( - - )
What is alturism
actor incurs a cost to provide benefit for a recipient (decrease their own fitness)
- cannot thrive if cannot be passed down genetically
What is eusocial hymenoptera
level of social organization, most individuals spend their lives serving the colony without reproducing
What is direct fitness
fitness from personal reproduction
What is indirect fitness
fitness from the reproduction of close genetic relatives
What is fitness
how good a particular genotype is at leaving a copy of its genes in the next generation
What is hamiltons rule
describes when altruistic behaviours are favoured
rB > C
r: degree of relatedness b/w 2 individuals
B: reproductive benefit to the recipient
C: reproductive cost to the actor
What is relatedness
probability that actor and recipients share gene in question
- depends on how genes were inherited
- relatedness of 0.5 to your mother
(50/50 change of inheriting gene from each parent) - 0.25 probabiliyt of shared genes from each parent, 0.5 relatedness to parent because 0.25 + 0.25
uncle, grandpanret r=0.25
first cousin r=0.125
dizygotic twin r=0.5
monozygotic r=1
What are the cues of kinship
mother’s association
co-residence with other children
What is phenotype matching
an evaluation of relatedness between individuals based on an assessment of phenotypic similarity
- being more trusting of people who look like kin
What is direct reciprocity
help each other and both benefit
What is indirect recirprocity
help others who have helped others –> establish good reputation and will help others
