Evolution

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When Darwin read Wallace’s essay, he knew he had to publish his findings

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Publication of “On The Origin of Species”

Darwin Presented Wallace’s Essay & Some Of His Work At A Scientific Conference of the Linnaean Society in July of 1858

Then He Started On his book “Origin of Species”

It Took Darwin 18 Months To Complete The Book

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Natural Variation and Artificial Selection

Abandoned The Idea That Species Were Perfect & Unchanging

Observed Significant Variation in All Species Observed

Observed Farmers Use Variation To Improve Crops & Livestock

Called Selective Breeding

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Natural Variation and Artificial Selection

Natural Variation

Differences Among Individuals Of A Species

Artificial Selection

Selective Breeding To Enhance Desired Traits Among Stock or Crops

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Natural Variation and Artificial Selection

Key Concept:

In Artificial Selection, Nature Provided The Variation Among Different Organisms, And Humans Selected Those Variations That They Found Useful

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Origin of Species

Concepts and Controversy

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Evolution By Natural Selection Concepts

The Struggle for Existence (compete for food, mates, space, water, etc.)

Survival of the Fittest (strongest able to survive and reproduce)

Descent with Modification (new species arise from common ancestor replacing less fit species)

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Survival of the Fittest

Fitness

Ability of an Individual To Survive & Reproduce

Adaptation

Inherited Characteristic That Increases an Organisms Chance for Survival

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Survival of the Fittest

Adaptations Can Be:

Physical

Speed, Camouflage, Claws, Quills, etc.

Behavioral

Solitary, Herds, Packs, Activity, etc.

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Survival of the Fittest

Fitness Is Central To The Process Of Evolution

Individuals With Low Fitness

Die

Produce Few Offspring

Survival of the Fittest

AKA Natural Selection

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