Darwin and Natural Selection

Evolution

Change in populations over time, as defined by Darwin as 'descent with modification'.

Natural Selection

Mechanism of evolution where advantageous traits become more common over generations.

Common Ancestor

The shared ancestor from which different species have evolved.

Adaptation

A heritable trait that increases an organism's chances of survival and reproduction.

Fitness

The ability of an organism to survive and reproduce in its environment.

Speciation

The formation of new and distinct species in the course of evolution.

Fifth Principle of Natural Selection

Inheritance - adaptive traits are passed to offspring.

Peppered Moth Example

An example of natural selection demonstrating variation, differential survival, and heredity.

Overproduction

The principle that more offspring are produced than can survive.

Geographic Isolation

A condition necessary for speciation where populations become separated by physical barriers.

James Hutton

A scientist who proposed that the Earth is very old and geological change is slow and continuous.

Alfred Wallace

Scientist who independently proposed the theory of natural selection.

Darwin's Finches

Examples of adaptive radiation showing beak variation linked to food sources and habitats.

Inheritance of Acquired Traits

Lamarck's incorrect theory that traits acquired during an organism's life can be passed to offspring.