Evolution Flashcards
Adaptations
Biological traits or characteristics that help an individual survive and reproduce in its habitat
- the working parts of evolution, the functional systems and subsystems
Adaptations perform specific functions that make an organism better suited to its _________
Environment
- adaptations exist to help one thrive in their physical environment
What are the 4 basic mechanisms of evolution
Natural selection
Mutation
Genetic drift
Migration
Natural selection
The differential survival and reproduction of organisms as a result of the heritable differences b/w them
What are the 3 essential components of natural selection?
- There are significant individual differences
- within any population, there is variation among individuals for any given characteristic - These differences affect individuals’ chances of surviving and reproducing, causing differential reproduction
- The traits that give rise to differential reproduction have a genetic basis, meaning they are heritable
- the offspring of successful reproducers will resemble their parents with respect to these variable characteristics
_________ __________ is the process through which natural selection operates
Selective transmission
________ heritable traits are selectively transmitted across generations
Favourable
The selective transmission of heritable traits results in ____________ changes
Population
- the most suitable traits will be passed on to the next generation
The specific characteristics that are best adapted for survival and reproduction are going to be reproduced at ________ rates
Higher
Stabilizing selection
Selection against any sort of departure from the species-typical adaptive design
- this sort of selection tends to keep traits stable over generations
Readily observable natural selection is _______ and ________
Minimal and reversible
Fitness (biology meaning)
About reproductive success, not physical fitness
Darwinian fitness
Average reproductive success of a genotype relative to alternative genotypes
Evolution
Change in gene frequencies over generations, in part due to the introduction of new gene variants via mutation
Natural selection can act on mate-finding to produce ________ selection
Sexual
Evolutionary pressures change across ______ generations
Successive
Sexual selection
The component of natural selection that acts on traits that influence an organism’s ability to obtain a mate, resulting in differential reproductive success
Female choice & combat success are subtypes of _________ selection
Sexual
Inter-sexual selection
Involves an interaction between males and females
- female choice (mate choice preferences)
Example of inter-sexual selection
Peacocks
Intra-sexual selection
Involves success in combat with other males
- male competition
Example of intra-sexual selection
Elks
Mate choice preferences
- female choice picks out males with the best resistance to diseases
- best genes for being healthy
Species can be identified by different species-typical ___________
Behaviours
What are the 4 parts of species-typical behaviour
- movement (topography)
- habitat preference
- group size
- social system
Natural selection favours the “__________ gene”
Selfish
What is it called when it has:
Positive effect on actor’s well-being
Positive effect on recipient’s well-being
Cooperation
What is it called when it has:
Positive effect on actor’s well-being
Negative effect on recipient’s well-being
Selfish
What is it called when it has:
Negative effect on actor’s well-being
Positive effect on recipient’s well-being
Altruism
What is it called when it has:
Negative effect on actor’s well-being
Negative effect on recipient’s well-being
Spite
Adaptations must increase ___________ of the gene, not necessarily the group
Success
- selection must be good for the gene, regardless of how it acts on the group
_____________ in groups increase personal success of obtaining food
Foraging
There is a trade-off between foraging for ________ and scanning for _________
There is a trade-off between foraging for FOOD and scanning for PREDATORS
- foraging in groups ensures more time for foraging over scanning
Altruism
Behaviour in which the actor incurs a cost to provide a benefit to a recipient
- altruism can not thrive if it cannot be passed down genetically
Altruists ______ their own fitness when helping others
Decrease
Eusocial Hymenoptera
In this level of social organization, most individuals spend their lives serving the colony without reproducing
- includes all ants, some bees and some wasps
Genes for altruism could be successful if they helped _____________ copies of themselves
Identical
*Known as INCLUSIVE FITNESS
Direct fitness
Fitness from personal reproduction
Indirect fitness
Fitness from the reproduction of close genetic relatives
Direct fitness + indirect fitness = ?
Inclusive fitness
What is Hamilton’s Rule’s equation?
rB > C
r = the relatedness of the individuals
- multiplied by the probability that the recipients actually have identical copies of the same gene or coefficient of relatedness
B = the reproductive benefit to the recipients
C = the reproductive cost to the actor
How is fitness measured?
Measured by the number of the copies of its genes left in the next generation
Probability that actor and recipient share gene in question
Relatedness
- ## depends on how genes were inherited
What is the relatedness to parents?
About 50% to either parent
What is the relatedness to full siblings?
About 50%
What does Hamilton’s Rule predicts?
Predicts theoretical adaptive behaviours
What explains cases of aggression and abuse in humans?
Relatedness
Cues of kinship
- Mother’s association
- Co-residence with other children
Alarm calls
Altruistic warning of approaching predators
- females give calls more often when they live near kin
- males leave kin early and almost never give alarm calls
Phenotype matching
An evaluation of relatedness b/w individuals based on an assessment of phenotypic similarity
Direct reciprocity
Situations in which individuals help each other and both benefits
Indirect reciprocity
Occurs when individuals help others who have helped others
- when helping others, you get a good reputation for yourself and overall will get more help from neighbors compared to individuals who never helped at all
- people are more generous and less likely to break the rules when they are observed by others
What does evolutionary psychology reveal about human behaviour today?
- adaptations from the evolutionary past continue to affect our behaviours today
- sex differences in reproductive success drive mate selection preference
- outcome variance can drive different solutions to the same problems
Psychological mechanisms + input from environment = ?
Behaviour
What are the different adaptive problems different sexes face?
- metabolic demands of reproduction
- parental investment
- genetic cuckoldry
Sexual over perception bias leads _______ to over-infer sexual interest
Males
What is a “post-hoc” explanation?
Have some type of observations then making a story about it
What is a “a priori” prediction?
Have some type of theory (the way to do good science)
- it’s better to have that theory first then collect the data
Naturalistic fallacy
A leap from IS to SHOULD BE
Moralistic fallacy
A leap from SHOULD BE to IS
