Evolution

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Embryonic Structures Of Different Species Show Significant Similarities

Embryo – early stages of vertebrate development

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Human Fetus – 5 weeks

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Chicken

Turtle

Rat

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Review

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Darwin's Theory

Individual Organisms In Nature Differ From One Another. Some Of This Variation Is Inherited

Organisms In Nature Produce More Offspring Than Can Survive, And Many Of These Offspring Do No Reproduce

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Darwin's Theory

Because More Organisms Are Produced Than Can Survive, Members Of Each Species Must Compete For Limited Resources

Because Each Organism Is Unique, Each Has Different Advantages & Disadvantages In The Struggle For Existence

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Darwin's Theory

Individuals Best Suited To Their Environment Survive & Reproduce Successfully – Passing Their Traits To Their Offspring.

Species Change Over Time. Over Long Periods, Natural Selection Causes Changes That May Eventually Lead To New Species

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Darwin's Theory

Species Alive Today Have Descended With Modifications From Species That Lived In The Past

All Organisms On Earth Are United Into A Single Tree Of Life By Common Descent

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