How can we help?

You can also find more resources in our Help Center.

24 terms

Evolution 8th grade

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.
Change in a kind of organism over time; process by which modern organisms have descended from ancient organisms.
A process typically caused by the genetic isolation from a main population resulting in a new genetically distinct species.
Charles Darwin
English natural scientist who formulated a theory of evolution by natural selection (1809-1882)
HMS Beagle
5 yr trip to map the coast of S. America, Darwin studied a wide variety of plants and amimals
Sexual Selection
An evolutionary mechanism by which traits that increase the ability of individuals to attract or acquire mates appear with increasing frequency in a population; selection in which a mate is chosen on the basis of a particular trait or traits
Artificial Selection
Selection by humans for breeding of useful traits from the natural variation among different organisms
A change in the nucleotide-base sequence of a gene or DNA molecule that increases genetic variation
Beneficial Mutation
any change to the genetic code that results in noticeable physiological changes that are of benefit to the organism
Harmful Mutation
is a mutation that decreases the fitness of the organism.
The biological process whereby genetic factors are transmitted from one generation to the next
Preserved remains of once-living organisms. Evidence that supports the Theory of Evolution
Homologous Structures
Structures that have different mature forms in different organisms but develop from the same embryonic tissues. Provides evidence supporting the Theory of Evolution
Analagous Structures
Similar function but different structure - does not show common ancestry - Ex: butterfly wing and bat wing). Not considered evidence of evolution
Vestigial Structures
A structure that is present in an organism but no longer serves its original purpose. Evidence of evolution
Survival of the Fittest
Process by which individuals that are better suited to their environment survive and reproduce most successfully; also called natural selection
A characteristic that improves an individual's ability to survive and reproduce in a particular environment.
Evolutionary change in which adaptations in one species act as a selective force on a second species, inducing adaptations that in turn act as a selective force on the first species; mutual influence on the evolution of two different interacting species.
A procedure in which the reinforcement of a previously reinforced behavior is discontinued. Also may be used to describe the "process" by which a previously learned behavior disappears as a result of non-reinforcement.
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.
Ability of an organism to survive and reproduce in its environment
Over Reproduction
The fact that all organisms have the capability to and do reproduce more offspring than could ever survive
Any difference between individuals of the same species.
Struggle to survive
Part of natural selection in which some individuals die from starvation, competition, disease, or predation

Flickr Creative Commons Images

Some images used in this set are licensed under the Creative Commons through
Click to see the original works with their full license.