Evolution/Natural Selection

Mechanism of evolution

Mechanism of evolution

Natural selection

Natural Selection

Organisms with traits better-suited to their environment survive and reproduce more often (This causes traits to change over time).

Biodiversity

The variety of living things in a given area (habitat, ecosystem)

Genetic Variation

Organisms belonging to the same species have different genes and traits. Some may be darker or lighter in color, some are taller for shorter, etc.

Population

a group of organisms of the same species living in the same area.

Adaptation

A trait that helps a population survive (Giraffe's long neck).

Population

A group organisms of the same species living in a particular area at the same time

Evolution

the change in genetics of a species over time

Mutation

the process in which DNA changes result in new alleles not inherited from parents

Extinction

occurs when the last individual of a species dies

Charles Darwin

English natural scientist who formulated a theory of evolution by natural selection

Competition

When two or more organisms struggle for the same resource (food, water, light, space, mates, nesting sites) but there is a limited amount so not enough for all.

Species

A group of similar organisms that can breed and produce fertile offspring.

advantageous traits

traits that benefit a species and allows to survive and reproduce and pass those traits on to the next generation

Example of genetic variation

Peppered moths

Fossil

The preserved remains or traces of an organism that lived in the past

homologous structures

Structures in different species that are similar because of common ancestry.

common ancestor

An ancestral species from which later species evolved

vestigial structures

A structure that is present in an organism but no longer serves its original purpose

Embryology evidence for evolution

The early stages of embryos of many animals with backbones are very similar.

geologic time scale

A record of the geologic events and life forms in Earth's history.

DNA

deoxyribonucleic acid

DNA evidence for evolution

Can be analyzed to compared amino acid sequence differences. The more differences, the further they are on the evolutionary tree.