Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.
A group of similar organisms that can breed and produce fertile offspring.
A trace of an ancient organism that has been preserved in rock.
A principle that states that geologic change occurs suddenly
Principle that states that the changes in landforms result from slow changes over a long period of time
Theory that states that the geologic processes that shape Earth are uniform through time
Differences in physical traits of an individual from the group in which it belongs
Inherited trait that is selected for over time because it allows organisms to better survive in their environment
Process by which humans modify a species by breeding it for certain traits
Ability of a trait to be passed from one generation to the next
Mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals
All of the individuals of a species that live in the same area
Measure of an organism's ability to survive and produce offspring relative to other members of a population
Study of the distribution of organisms around the world
Body part that is similar in structure on different organisms but performs different functions
Body part that is similar in function as a body part of another organism but is structurally different
Remnants of an organ or structure that functioned in an earlier ancestor
Collection of alleles (genes) found in all of the individuals of a population
Proportion of one allele, compared with all the alleles for that trait, in the gene pool
Distribution in a population in which allele frequency is highest near the mean range value and decreases progressively toward each extreme end
Observable change in the allele frequencies of a population over a few generations
Pathway of natural selection in which one uncommon phenotype is selected over a more common phenotype
Pathway of natural selection in which intermediate phenotypes are selected over phenotypes at both extremes
Pathway of natural selection in which two opposite, but equally uncommon, phenotypes are selected over the most common phenotype
Physical movement of alleles from one population to another
Change in allele frequencies due to chance alone, occurring most commonly in small populations
Genetic drift that results from an event that drastically reduces the size of a population
Genetic drift that occurs after a small number of individuals colonize a new area
Selection in which certain traits enhance mating success; traits are, therefore passed on to offspring
Condition in which a population's allele frequencies for a given trait do not change from generation to generation
Final stage in speciation, in which members of isolated populations are either no longer able to mate or no longer able to produce viable offspring
Evolution of two or more species from one ancestral species
Isolation between populations due to differences in courtship or mating behavior
Isolation between populations due to physical barriers
Isolation between populations due to barriers related to time, such as differences in mating periods or differences in the time of day that individuals are most active
Evolution toward similar characteristics in unrelated species, resulting from adaptations to similar environmental conditions
Evolution of one or more closely related species into different species; resulting from adaptations to different environmental conditions
Process in which two or more species evolve in response to changes in each other
Elimination of a species from Earth
Theory that states taht speciation occurs suddenly and rapidly followed by long periods of little evolutionary change
Process by which one species evolves and gives rise to many descendant species that occupy different ecological niches
Estimate of the age of a fossil based on the location of fossils in strata
Technique that measures the natural decay rate of isotopes to calculate the age of material
Form of an element that has the same number of protons but a different number of neutrons as another elements
Amount of time it takes for half of the isotope in a sample to decay into its product isotope
Fossil of an organism that existed during only specific spans of geological time across large geographic areas
Geologic time scale
Time scale representing the history of Earth
Second largest unit of geological time, lasting tens to hundreds of millions of years and consisting of two or more periods
Unit of geologic time that lasts tens of millions of years and is associated with a particular type of rock system. (the 3rd largest)
Smallest unit of geological time, lasting several million years
Rotating cloud of gas and dust
RNA molecule that can catalyze specific chemical reactions
Bacteria that can carry out photosynthesis
Ecological relationship in which one organism lives within the body of another
Era of geological time (from 544 to 248 million years ago) during which members of every major animal group alive today evolved
Earliest part of the Paleozoic era, when a huge diversity of animal species evolved
Era during which dinosaurs roamed Earth (from 248 million years ago to 65 million years ago)
Geological time period that began 65 million years ago and continues today
Billion years ago
Million years ago
Name for the time in earth's early history that accounts for ninety percent of earth's time, but only cellular organisms lived.
Embryos of vertebrates share many anatomical homologies. (Supports the concept of evolution)
Molecular comparisons (DNA and proteins)
Universal genetic code and the conserved sequences of amino acids in proteins and nucleotides in DNA
Inorganic molecules used energy from sun to become organic
Found that organic molecules can form in a strongly reducing atmosphere
Organic molecules may have arrived on Earth through meteorite or asteroid impacts
Hydrothermal vents produce sulfur that mixes with ocean water to make compartments of rock. Walls containing these compartments could have served as the first cell membranes.
Lipid molecules spontaneously form membrane-enclosed spaces called liposomes.
What is the first genetic material?
First organisms to live on earth?
Theory of endosymbiosis
This theory states that cell organelles, like mitochondria, were once tiny, free-living prokaryotic organisms that took up permanent residence inside larger prokaryotic organisms.
The formation of a new species as a result of an ancestral population's becoming isolated by a geographic barrier.
The formation of a new species as a result of a genetic change that produces a reproductive barrier between the changed population (mutants) and the parent population. No geographic barrier is present.
Hardy- Weinberg principle
Principle that allele frequencies in a population will remain constant unless one or more factors cause the frequencies to change
Five factors that lead to evolution
Genetic drift, gene flow, mutation, sexual selection, natural selection
List the conditions that need to be met in order it maintain Hardy-Weinberg equilibrium?
The population must be very large in size. It must be isolated from other populations. (no gene flow) No mutations. Random mating. No natural selection.
Two Hardy-Weinberg equations to calculate genotype and allele frequencies