Unit 9: Population Genetics Flashcards
Acquired inheritance
a theory proposed by Lamarck that an organism will develop a trait by using it; for example, a giraffe’s neck will get longer because of stretching to reach leaves high in a tree
Acquired traits
traits an organism develops within its lifetime, such as strong muscles
Adaptation
any function, structure, or behavior that allows an organism to be successful in their environment so they survive and reproduce
Adaptive radiation
the process by which a single species evolved into many new species to fill available niches
Allele frequency
how often an allele occurs in a gene pool relative to the other alleles for that gene
Allopactric speciation
new species form when a geographic barrier, such as a canyon or river,
separates a population
Analogous structures
structures that are similar in unrelated organisms because the structures perform the same job, but they are not inherited from a common ancestor
Artificial selection
breeding done by humans to select certain traits or characteristics in the plant or animal
Behavioral isolation
a type of reproductive isolation that prevents organisms from reproducing due to the presence or absence of certain behaviors (such as mating rituals)
Biogeography
the study of the distribution of organisms, species, ecosystems, and biomes around the world
Bottleneck effect
a type of genetic drift that occurs when a population suddenly gets smaller due to a natural disaster
Camouflage
species has an appearance (color, shape, or pattern) that help blend into the background
Charles Darwin
an English naturalist who developed the theory of evolution
Comparative anatomy (morphology)
the study of the similarities and differences in the structures of
different species
Comparative embryology
the study of similarities and differences in the embryos of different species
Directional stabilization
selection occurs when one of the two extreme phenotypes is selected, so the majority of the population’s characteristics shift towards that end
Disruptive selection
selection that occurs when phenotypes in the middle of the range are selected against, so two different phenotypes develop
Evolution
a change in gene frequencies within a population
Fitness
an organism’s ability to survive and produce fertile offspring