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Adaptation is one of the life processes carried out by all living things.

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Natural Selection

Fur color Brown Tan Black White

Age at death 6 months 8 months 4 months 2 months# of pups 6 12 2 0Running speed 8 m/ min 6 m/ min 9 m/ min 7 m/ min

Other Bit 5 birds that tried to attack

her pups.

Chases off 2 snakes that

wanted to eat her pups.

Relocated her pups after her

den was flooded during

high tide.

Had the deepest and

most well hidden den on

the beach.

Which mouse is the fittest? Why?

Adaptation is one of the life

processes carried out by all living

things.

The organisms best suited to their

environment have more chance of survival if the species falls upon hard

times.

This idea is known as survival of the survival of the

fittestfittest.

Natural selection is the process by which these “fit” individuals survive & reproduce to pass on the advantageous traits to their offspring.

This provides a mechanism for an

entire population to adapt to the

environment & thus will ensure survival.

Charles Charles Darwin’s Darwin’s

was a was a biologistbiologist

who studied who studied animals of animals of

the the Galapagos Galapagos Islands in Islands in

1835.1835.

Darwin studied finches and Darwin studied finches and how their beak how their beak adaptationsadaptations have allowed them to adapt have allowed them to adapt to take advantage of food to take advantage of food

sources in different sources in different ecological nichesecological niches..

His studies led him to come His studies led him to come up with a up with a theorytheory based on based on

the process of natural the process of natural selection.selection.

Charles Charles Darwin’s Darwin’s Theory of Theory of Natural Natural

Selection:Selection:

Organisms produce more offspring than

can survive.

There is competition among offspring for food, space & other

resources.

There are variations among the offspring of an organism caused by

genetic differences.

Individuals with certain traits are better suited to survive in their

environment than those without the

traits

Organisms that survive & reproduce pass the genes for their useful

traits to the next generation.

Adaptations can only happen if there is variety within the offspring of a species.

This variety is caused by genetic variation, the normal differences that exist among individuals of the same species.

Greater variation can be caused by

mutations which are caused by random changes in genes.

Mutations can be helpful or

harmful.

Selective breeding is the process of

breeding plants and animals for particular

genetic traits.

Selective breeding is most often seen with domestic animals like cats and dogs which are bred for specific traits such as size, health, looks, fur type, or their specialized job.

Selective breeding is also common in

organisms used for consumption such as cattle, chickens, pigs, fruits and vegetables.

Traits that are favorable in these organisms include

growth rate, survival rate, disease

resistance, and meat/ egg/ flesh quality.

Fur color Brown Tan Black White

Age at death 6 months 8 months 4 months 2 months# of pups 6 12 2 0Running speed 8 m/ min 6 m/ min 9 m/ min 7 m/ min

Other Bit 5 birds that tried to attack

her pups.

Chases off 2 snakes that

wanted to eat her pups.

Relocated her pups after her

den was flooded during

high tide.

Had the deepest and

most well hidden den on

the beach.

NOW? Which mouse is the fittest? Why?

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