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Bio 171 Lecture 19

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organisms
evolutionary processes affect all _____ on earth
continue
evolutionary processes _____ to impact populations and species
practical
understanding evolution has _____ applications such as fighting diseases and saving endangered species
phenotypes
natural selection act's on individual's _____ and the population evolves (allele frequencies change)
Origin of Species
publication about evolution by Darwin
pinnacle
Humans are NOT the ______ of evolution, simply part of the eukarya tree
speciation
small evolutionary changes accumulate over long time periods and generate large evolutionary changes like ____
progressive
evolution is NOT ______
current
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
HWE
natural and sexual
___ and ____ selection are the only processes that produce adaptations
adaptations
heritable traits that increase survival/reproductive success
selection
_____ is the only evolutionary process that can consistantly produce adaptations
HWE
natural selection can move populations away from _______
alleles
_____ increase or decrease in frequency based on an organism's fitness
fitness
alleles increase or decrease in frequency based on an organism's _____
fitness
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
fast
generation time is generally ___ for bacteria and archaea
slower
generation time is generally ____ for eukaryotes as compared to bacteria
tuberculosis
bacteria/disease that kills more adult humans than any other virus or bacterium (TB)
antibiotic-resistant
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
allele
in directional selection, 1 ____ is favored
fixed
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
environments
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
heterozygous
balancing selection favors ______ individuals
malaria
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
mean
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
eyes
example of regressive evolution: cave species commonly lose their ____
reduced
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
morphology
the physical form of an organism