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evolutionary processes affect all _____ on earth


evolutionary processes _____ to impact populations and species


understanding evolution has _____ applications such as fighting diseases and saving endangered species


natural selection act's on individual's _____ and the population evolves (allele frequencies change)

Origin of Species

publication about evolution by Darwin


Humans are NOT the ______ of evolution, simply part of the eukarya tree


small evolutionary changes accumulate over long time periods and generate large evolutionary changes like ____


evolution is NOT ______


natural selection reduces the representation of less advantagous traits in the _____ environment (but environments change!)

reproductive success

as environments change, the traits that lead to increased ______ can also change

natural selection

________ can move populations away from HWE

hardy-weinburg equilibrium


natural and sexual

___ and ____ selection are the only processes that produce adaptations


heritable traits that increase survival/reproductive success


_____ is the only evolutionary process that can consistantly produce adaptations


natural selection can move populations away from _______


_____ increase or decrease in frequency based on an organism's fitness


alleles increase or decrease in frequency based on an organism's _____


the number of viable offspring the organism is able to produce

relative fitnes

the fitness of an individual relative to other members of the population

generation time

timescale for evolution by natural selection depends on _____ of organism


generation time is generally ___ for bacteria and archaea


generation time is generally ____ for eukaryotes as compared to bacteria


bacteria/disease that kills more adult humans than any other virus or bacterium (TB)


TB is on the rise as ______ strains evolve and spread

sanitation, nutrition, antibiotics

_____, _____, ______ greatly reduced cases of TB over 1950-1990 but now it is coming back

directional selection

selection that changes the average value of a trait


in directional selection, 1 ____ is favored


an allele with a frequency of 100% is said to be ____

genetic diversity

with directional selection, over time _____ is reduced

phenotypic divergence

directional artificial selection drives _____ in dogs and domesticated crops

directional sexual

increase in tail length of male widowbirds due to _______ selection


human activities are changing _____

unintended directional

human activities (changing environments) are causing ___________ natural selection

antibiotic resistance

directional natural selection unintentionally caused by humans: hundreds of disease causing bacteria have evolved resistance to antibiotics

pesticide resistance

directional natural selection unintentionally caused by humans: over 600 species of insects and mites have evolved resistance to pesticides

herbicide resistance

directional natural selection unintentionally caused by humans: hundreds of weedy plants have evolved resistance to herbicides

artifical selection

directional natural selection unintentionally caused by humans: this is NOT ____ (because is unintended)

balancing selection

a pattern of natural selection in which heterozygous individuals have higher fitness then homozygous individuals


balancing selection favors ______ individuals


example of balancing selection: carriers of sickle-cell anemia are more resistant to than HH genotypes

stabilizing selection

reduces the amount of variation in a trait

intermediate phenotypes

in stabilizing selection, individuals with _____ are favored

genetic variation

stabilizing selection tends to reduce _____ in a trait

human birth weight

example of stabilizing selection

disruptive selection

increases the amount of variation in a trait

extreme phenotypes

disruptive selection occurs when _____ are favored


disruptive selection does not change the ____ value of a trait

stabilizing selection

disruptive selection has an effect that is opposite of ______

regressive evolution

loss of complex structures


example of regressive evolution: cave species commonly lose their ____


if having ____ morphological complexity leads to higher fitness, then the frequency of those alleles will increase in a population (regressive evolution)

parasitic worms

example of regressive evolution: many ____ have very simple morphologies


the physical form of an organism

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