adaptation Flashcards
what are exaptations
adaptations that have arisen after a change in function
–> originally adaptations, evolve in a different context and later co-opted for current, fitness-enhancing function
what is adaptation (2)
1) trait maintined by natural selection for its current function
2) process that produces phenotypes that enhances survival/reproduction of organism in current environ.
what is acclimation
an individual organism adjusts to change in environment to minimize effects of stressors/maintain performance
–> changes are not inherited
(T/F) individuals can evolve
F
individuals cannot evolve, only populations can evolve
what is an adaptationist fairty tale
untested/unsupported explanation for adaptive value of a phenotype
how do you demonstrate a trait is adaptive
determine function and show how function increases fitness in current environ.
what is the comparative method
correlate differences among populations/species with variation in presemed selective agent
what is reciprocal transplant
fitness of individuals is quanitfies in 2 environments –> local adaptation makes a clear prediction
what are complex adaptations
often cosnist of interdependent parts that can’t work on their own
–> built over periods of time with various intermediate steps
(ex. the eye)
–>exaptation can contribute
what are darwinian demons
‘ideal’ organism that would simultaneously maximize all aspects of fitness
–> breeding immediately after birth, produce offspring, continue with no decline
why are there no darwinian demons? (5)
1) selection acts on existing variation
2) historical constraints (evolutionary history can impact future evolution
3) trade-offs
4)environmental change (natural selection lacks foresight)
5) other evolutionary processes may matter
what are trade-offs
optimal design for one function may differ from that for another function
–> increase in performance of one trait causes decrease in another
