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vocab

TermDefinition
evolution the gradual development of something, especially from a simple to a more complex form
natural selection the process whereby organisms better adapted to their environment tend to survive and produce more offspring. The theory of its action was first fully expounded by Charles Darwin and is now believed to be the main process that brings about evolution.
Charles Darwin a English naturalist, geologist and biologist, best known for his contributions to the science of evolution. His proposition that all species of life have descended over time from common ancestors is now widely accepted
fitness Fitness is usually discussed in terms of genotypes, or collection of genes. Genotype fitness is the average fitness of all individuals in a population that have a specific genotype.
variability lack of consistency or fixed pattern; liability to vary or change.
inheritability capable of being transmitted by heredity from one generation to a later one. capable of being inherited. rare capable of inheriting; having the right to inherit.
artificial selection the intentional reproduction of individuals in a population that have desirable traits. In organisms that reproduce sexually, two adults that possess a desired trait — such as two parent plants that are tall — are bred together.
adaptation something produced by adapting: . any alteration in the structure or function of an organism or any of its parts that results from natural selection and by which the organism becomes better fitted to survive and multiply in its environment
structural adaptation Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
mimicry he close external resemblance of an animal or plant (or part of one) to another animal, plant, or inanimate object.
camouflage hide or disguise the presence of (a person, animal, or object) by means of camouflage.
fossil record Fossil record, history of life as documented by fossils, the remains or imprints of the organisms from earlier geological periods preserved in sedimentary rock
homologous structure A homologous structure it's when very different animals have bones that appear very similar in form or function and seem to be related.
analogous structure similarity of function and superficial resemblance of structures that have different origins. For example, the wings of a fly, a moth, and a bird are analogous because they developed independently as adaptations to a common function—flying.
vestigial structure/organ s an anatomical feature or behavior that no longer seems to have a purpose in the current form of an organism of the given species.
embryology the branch of biology and medicine concerned with the study of embryos and their development.
gene pool the stock of different genes in an interbreeding population
genetic drift variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce
allele/gene frequency Allele frequency, or gene frequency, is the relative frequency of an allele at a particular locus in a population, expressed as a fraction or percentage. Specifically, it is the fraction of all chromosomes in the population that carry that allele.
stabilizing selection Stabilizing selection (not to be confused with negative or purifying selection) is a type of natural selection in which the population mean stabilizes on a particular non-extreme trait value.
bottleneck effect A population bottleneck or genetic bottleneck is a sharp reduction in the size of a population due to environmental events (such as famines, earthquakes, floods, fires, disease, or droughts) or human activities (such as genocide).
founder effect In population genetics, the founder effect is the loss of genetic variation that occurs when a new population is established by a very small number of individuals from a larger population.
fossil Any preserved evidence of life from a past geological age, such as the impressions and remains of organisms embedded in stratified rocks.
speciation the formation of new and distinct species in the course of evolution.
directional selection a mode of natural selection in which a single phenotype is favored, causing the allele frequency to continuously shift in one direction. a mode of natural selection in which extreme values for a trait are favored over intermediate values
disruptive selection describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.
Created by: hania l