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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 beak number of fingers color of the fur thickness or thinness of fur shape of the nose or ears . - PowerPoint PPT Presentation
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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!!!
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
