43 terms

Evolution Flash Cards

Mrs. Cowan, Hiram High School, 9th
A changing to fit new conditions
Analogous Structure
Similar in function but not structure
Artificial Selection
Breeding organisms with specific traits in order to produce offspring with identical traits.
Behavioral Isolation
Form of reproductive isolation in which two populations have differences in courtship rituals or other types of behavior that prevent them from interbreeding.
Dealing with the geographical distribution of animals and plants
Bottleneck Effect
Genetic drift resulting from the reduction of a population, typically by a natural disaster, such that the surviving population is no longer genetically representative of the original population.
A principle that states that geologic change occurs suddenly
"Age of mammals"
Charles Darwin
1809-1882; Field: geology, biology; Contributions: transmutation of species, natural selection, evolution by common descent; Studies: "The Origin of Species" catalogs his voyage on the Beagle
Process by which two species evolve in response to changes in each other
Convergent Evolution
Process by which unrelated organisms independently evolve similarities when adapting to similar environments
Bacteria that can carry out photosynthesis
Directional Selection
Form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve
Disruptive Selection
Form of natural selection in which a single curve splits into two; occurs when individuals at the upper and lower ends of a distribution curve have higher fitness than individuals near the middle
Divergent Evolution
When two or more species sharing a common ancestor become more different over time
Process through which early prokaryotic cells are thought to have engulfed other, smaller cells and eventually incorporated them as organelles; these cells evolved into modern-day eukaryotes.
Subdivisions of the periods of the geologic time scale.
Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.
A species dies out forever.
Ability of an organism to survive and reproduce in its environment
A preserved remnant or impression of an organism that lived in the past.
Founder Effect
Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population.
Gene Flow
Movement of alleles into or out of a population due to the migration of individuals to or from the population
Gene Pool
Combined genetic information of all the members of a particular population
Genetic Drift
A change in the allele frequency of a population as a result of chance events rather than natural selection.
Geographic Isolation
form of reproductive isolation in which two populations are separated physically by geographic barriers such as rivers, mountains, or stretches of water
Geologic Time Scale
Earth's history organized into four eras: Precambrian, Paleozoic, Mesozoic, and Cenozoic
A proposed explanation in evolutionary biology stating that new species arise from the result of slight modifications (mutations and resulting phenotypic changes) over many generations.
Homologous Structure
Structures in different species that are similar because of common ancestry.
Index Fossil
A fossil known to have lived in a particular geologic age that can be used to date the rock layer in which it is found
Change in gene frequencies between populations of a species over time. Large changes
"Age of the Reptiles"
Change in gene frequencies between populations of a species over time. Small changes
Natural Selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
Normal Distribution
A bell-shaped curve, describing the spread of a characteristic throughout a population
An era occurring between 570 million and 230 million years ago, characterized by the advent of fish, insects, and reptiles
Reproductive Isolation
Separation of species or populations so that they cannot interbreed and produce fertile offspring
Sexual Selection
A form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates.
A process typically caused by the genetic isolation from a main population resulting in a new genetically distinct species.
Stabilizing Selection
Form of natural selection by which the center of the curve remains in its current position; occurs when individuals near the center of a distribution curve have higher fitness than individuals at either end
Temporal Isolation
Form of reproductive isolation in which two populations reproduce at different times
A principle that geologic processes that occurred in the past can be explained by current geologic processes
Vestigial Structure
Remnant of evolution, structure with no purpose