AP BIOLOGY VOCAB CH 19/21 Flashcards
perceived adaptation to the environment and the origin of new species as closely related processes
Darwin
perceived the idea of speciation
Wallace
visual evidence of change overtime
fossils
when new layers of sediment cover the old layers and compress them into layers of rock
strata
introduced inheritance of acquired traits, USE AND DISUSE
Lamarck
a change or the process of change by which an organism or species becomes better suited to its environment
adaptations
nonrandom differential success in reproduction, leads to accumulation of “good” genes
natural selection
man chooses
artificial selection
members of a population often vary their inherited traits and ALL species can produce more offspring than the environment can support (more COMPETITION)
Darwin’s observations
Those with favorable traits for an environment will survive and pass on favorable traits leading to more offspring.
Darwin’s inferences
same structure indicate common ancestry
homologous structures
structures that aren’t currently used but left over from an ancestor
vestigial structures:
the study of the geographic distribution of plants, animals, and other forms of life
biogeography
the movement of continents resulting from the motion of tectonic plates
continental drift
a species that can only survive in one geological area
endemic
a likeness often due to common origin
homology
differences among populations in genetically based traits across the natural geographic range of a species
geographic variation
original and continued source of variation
mutation
p^2 + 2pq + q^2 = 1 (p^2 = homozygous dominant, q^2 = homozygous recessive, 2pq = heterozygous)
Hardy Weinberg equilibrium
very large population
no sexual selection
no natural selection
no mutations
no gene flow (no immigration/emigration)
5 conditions of Hardy Weinberg
random, describes how allele frequencies fluctuate randomly, affects small populations → loss of genetic variation
genetic drift
genetic drift that occurs when a few individuals become isolated from a larger population
founder effect
a dramatic change causes the population to become very small and less diverse (no natural selection) (ex. Natural disaster)
bottleneck effect
immigration and emigration, tends to reduce differences between populations overtime
gene flow
describes the total number of offspring an organism has compared to the average number of offspring for the population
relative fitness
one extreme phenotype was selected for (ex. peppered moths)
directional selection
nature favors both extreme phenotypes (ex. bird beaks)
disruptive selection
nature favors the average phenotype (ex. infant birth weight)
stabilizing selection
usually the female chooses, results in sexual dimorphism
sexual selection
marked differences between the sexes in secondary sexual characteristics
sexual dimorphism
occurs when heterozygotes have a higher fitness than do both homozygotes (ex. heterozygous sickle cell disease is more advantageous than only normal cells or only sickle cells)
heterozygote advantage
when organisms not closely related independently evolve similar traits
convergent evolution
