WEEK 3: FUNCTION AND EVOLUTION Flashcards
What is divergent evolution?
evolution of diff features in common ancestor- results in diff between species
what is convergent evolution?
evolution of similar features in unrelated species due to similar environemental pressures
what are the behaviours with the function of maximising survival?
hide from predators
escape from predators
increase food eaten
reduce energetic costs
what are the behaviours with the function of aiding reproduction?
increasing attractiveness
increasing access to mates
increasing fecundity
increasing survival of young
in terms of complications to evolution, please describe “missing species”
where does behaviour come from if fossil record is incomplete?
in terms of complications to evolution, please describe “changed environment” and give an example
behaviour can develop in response to localised climatic changes which will increase fitness of the individual in the long term
for example, the tiger is different to other cats, as it likes bathing in water to be able to adapt to the tropics when before it was a cold-weather animal.
in terms of complications to evolution, please describe “changed selection pressures” and give an example
behaviours themselves can change the selective pressures of future generation
for example, a leopard hunting impalas and wilder beast. will they run or fight? depending on whether the fighters or runner survive (and then breed) will affect how evolution develops.
what is epistasis?
phenomenon where expression of one gene depends on the presence of other genes.
how does the adaptive landscape diagram work?
it’s only genetic combinations where epistasis is promoting good quality traits that reach the highest peaks in the adaptive landscape, and therefore possible.
how is evolutionary relatedness measured?
phylogenetic tree
