The document discusses how physical features in animals evolve over generations through natural selection to help animals obtain food, stay safe from predators, build homes, withstand weather, and attract mates. It provides examples of physical features like beak shape, number of fingers, fur color and thickness, and nose or ear shape. Defensive adaptations against predators through hiding, camouflage, group defense, fleeing, and warnings are also discussed. Natural selection requires that organisms produce more offspring than can survive, individuals vary in their characteristics, and characteristics are inherited from parents. Through natural selection, characteristics evolve over time to resemble those of better-suited ancestors who survive and reproduce more successfully.

1.  Animals depend on physical
features to:
 obtain food
 keep safe
 build homes
 withstand weather
 attract mates.

2.  Do not develop during an animal's life but over
many generations.
 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

3.  Defensive adaptations include:
 Predator avoidance
 Hiding and camouflage
 Group defense
 Fleeing
 Signal
 Warnings

4.  Many organisms avoid predators
by the use of cryptic coloration.
 A requirement of camouflage in
many cases is that the individual
choose an appropriate
background.

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

6. 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.

7. • 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.

8. • The process where only the organisms
best adapted to their environment tend
to survive.
• These survivors transmit their genetic
characteristics in their offspring to new
generations.
• Those less adapted, without the right
genetic characteristics tend to be
eliminated.

11.  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.

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

13.  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.

15.  Inmid 1950’s pollution
controls were introduced in
Britain and frequency of the
black moth form has declined
since then.

17.  http://www2.d125.org/~nfischer/Moth/defa
ult.htm
 Complete the sheet to accompany the
simulation