11.1 Mechanism of Evolution Flashcards
how does variation affect biological fitness
if the variation is helpful it will increase the fitness of the organism
an example of vartation
white vs dark fur for mice
will natural selection happen faster if the fitness of an organism is higher or lower
if it is lower like having dark fur on a white background
is natural selectoin a radomon process
no
Does natural selection involve individuals trying to adapt?
no, it’s about whole populations adapting to the trait not individual
vartation
changes in the gene pool over time
list the five fingers of evolution
Pinky- population shrinks
ring-mating
middle-mutation
index-movement, immigration
thumb-adaptions
3 requirements of natural selection
different alleles, the environment makes one variation more beneficial than another this increases the fitness of the organism, once variation gives individuals in the population a higher fitness so the variation will increase in the population over time
natural selection acts on what
populatoins not indivauls
adaptation
genetic variation that increases fitness
adaption is passed through what
germine not acquired through lifetime tho
types of selective pressures
sexual, psychological, physiological
desrcibe directional selectoin
moves from left to right
stabilizing selection
gets higher in the middle of the bell curve
disruptive selection
gets a bigger split in the middle of bell curve and turns into 2
how does emigration and immigration affect the gene frequency
more ff genes added or it could add more F genes
how is getnic drfit similar to natural selectoin
both changes in traits in a population
how is genetic drift different from natural selection
due to chance events vs due to adaptive change
What is the founder’s effect
small initial population
What is the bottleneck effect
natural disaster
gamete sampling
525 billion sperm cells in a lifetime only has 2 kids
parent sampling is
bottleneck effect and founders effect
how do alleles that don’t have large impact on fitness go along with selected traits
they can hitchhike if they are close they will link
describe mutations
they are random but constant they are a part of DNA replication and many are neutral, different populations have different mutations over time
