physical adaptations

Physical Adaptations Animals depend on physical

features to: obtain food keep safe build homes withstand weather attract mates.

Physical Adaptations Examples:

shape of a bird's beaknumber of fingerscolor of the furthickness or thinness of furshape of the nose or ears

Adaptation

The adjustment or changes in behavior, physical features, and structure of an organism to become more suited to an environment.

Natural Selection – Survival of the Fittest

Natural selection requires on three things:

1. Organisms produce more offspring than can survive.2. Individuals vary in their characteristics.3. Many characteristics are inherited by offspring from

their parents.

Logically then.......• Some individuals will be better suited to

their environment They will survive and reproduce

more successfully than individuals without those characteristics.

• Future generations: contain more genes from better-suited individuals.

• Result: characteristics will evolve over time to resemble those of the better-suited ancestors.

Natural Selection• Organisms best adapted to their

environment tend to survive.• Survivors give their genetic

characteristics to their offspring and to new generations.

• Those less adapted, without the right genetic characteristics tend to be ELIMINATED!!!

Natural Selection Video

Peppered Moth Video

Peppered Moths – Adaptation in Action

Two Kinds: White speckled moth Black moth

In early 1800’s dark form was very rare.

Dark form caused by dominant mutation that occurs spontaneously.

Peppered moths rest on trees and depend on camouflage for protection.

Peppered Moth Unpolluted Areas: trees are

covered in lichens and the light form of the moth is hard to see.

In mid 1800’s air pollution in British cities covered trees with soot.

In cities dark form became common and light form rare.

Peppered moth In mid 1950’s pollution

controls were introduced in Britain and frequency of the black moth form has declined since then.

Peppered Moth Simulation http://www2.d125.org/~

nfischer/Moth/default.htm Complete the sheet to accompany the

simulation