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The theory that simple chemical compounds in the ancient atmosphere and ocean combined by spontaneous chemical reactions to form larger, more complex substances, eventually leading to the origin of life and the start of biological evolution.
..., geysers on the seafloor, created where tectonic plates move apart, spewing hot and mineral-rich water into cold ocean depths
The different kinds of genetic information found in a particular group - family, population, species, etc.
..., Changes in the genetic composition of a population through successive generations.
..., process by which individuals that are better suited to their environment survive and reproduce most successfully; also called survival of the fittest
theory of evolution
..., This theory stated that animals could evolve from other animals in order to adapt to their environments. This theory was not widely accepted for it could possibly account for humans which would defeat the whole purpose of creationism
..., movement of alleles into or out of a population due to the migration of individuals to or from the population
..., evolution on the smallest scale—a generation-to-generation change in the frequencies of alleles within a population
..., Species with a broad ecological niche. They can live in many different places, eat a variety of foods, and tolerate a wide range of environmental conditions. Examples are flies, cockroaches, mice, rats, and human beings.
..., Species with a narrow ecological niche. They may be able to live in only one type of habitat, tolerate only a narrow range of climatic and other environmental conditions, or use only one type or a few types of food.
..., The process by which a new species evolves from a prior species, the most basic process in macroevolution.
..., Phenomenon in which individuals with adaptive genetic traits produce more living offspring than do individuals without such traits.
..., separation of populations as a result of geographic change or migration to geographically isolated places
..., separation of species that prevents them from interbreeding and producing fertile offspring
..., any heritable trait that enables an organism to survive through natural selections and reproduce better under prevailing environmental conditions
directional natural selection
..., Selection that causes a shift in allele frequency such that one more more alleles become more common over time.
..., when two or more species sharing a common ancestor become more different over time
stabilizing natural selection
..., a population of organisms shift towards the average trait. This is the most common form of natural selection.
diversifying natural selection
..., Enviromental conditions favor individuals at both extremes, reduces the individual with normal traits
..., normal extinction of various species as a result of changes in local environmental conditions
..., The evolution of two or more species that is due to mutual influence, often in a way that makes the relationship more mutually beneficial
..., A specific role of a species within an ecosystem, including its use of resources, and relationships with other species.
..., periods of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles, or niches, in their communities
..., (ecology) the status of an organism within its environment and community (affecting its survival as a species)
gradualist model of evolution
..., changes evolve little by little in populations and species become adapt to environments
punctuated equilibrium hypothesis
..., Theory that suggests that new kinds of organisms arise as a result of drastic environmental changes, which cause drastic genetic changes.
..., the full range of conditions that a species can tolerate and resources it can use
..., when a species occupies a smaller niche than it would in the absence of competition.
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