Bio 171 Lecture 19
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waterdancer430 on February 20, 2012
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54 terms
Terms | Definitions |
|---|---|
 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 |
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