Natural Selection Final 2026

a specific characteristic of an individual organism

trait

an instruction for making a protein molecule

gene

the process by which the distribution of traits in a population changes over many generations

natural selection

an organism that holds an ecosystem together

keystone species

the number of individuals with each trait in a population

distribution

the underlying medium, surface, or environment on which organisms live, move, and interact

substrate

a trait that makes it more likely that an individual will survive in a specific environment

adaptive trait

a trait that makes it less likely that an individual will survive in a specific environment

non-adaptive trait

a group of individuals born and living at about the same time

generation

a sharp reduction in the size of a population due to environmental events (like fires or floods) or human activities

bottleneck

any difference in traits between individual organisms

variation

a random change to a gene that sometimes results in a new trait

mutation

measures an organisms relative ability to survive, find a mate, produce offspring and pass its genes on to the next generation

fitness

a group of the same type of organism living in the same area

population

the scientific study of the similarities and differences in the physical structures of different species

comparative anatomy

orginisims with heritable traits better suited to their environment are more likely to survive and reproduce

adaptation

any non living physical or chemical component of an environment that acts as a selection pressure, determining which organisms survive and reproduce

abiotic factor

any living component of an ecosystem such as predators prey parasites or competitors that influences the survival and reproduction of an organism

biotic factor

everything (living or nonliving) that surrounds an organism

enviornment

a graph that shows how characteristics or values are distributed within a group

histogram

a scientist who studies ancient life and the fossil record

paleontologist

a scientist eho studies past human life and culture by analyzing the physical artifacts, structures, and remains people left behind

archeologists

the intentional process of breeding plants or animals to develop specific desirable traits

selective breeding