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neck feathers. crop. tail feathers. Several key insights led to Darwin’s idea for natural selection. . Darwin noticed a lot of variation in domesticated plants and animals. Artificial selection is the process by which humans select traits through breeding.
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neck feathers crop tail feathers Several key insights led to Darwin’s idea for natural selection. • Darwin noticed a lot of variation in domesticated plants and animals. • Artificial selection is the process by which humans select traits through breeding.
Hundreds to thousandsof years of breeding(artificial selection) Ancestral dog (wolf) Figure 13.2B Figure 13.2A 0 • Darwin found convincing evidence for his ideas in the results of artificial selection • The selective breeding of domesticated plants and animals
Natural selection is a mechanism by which individuals that have inherited beneficial adaptations produce more offspring on average than do other individuals. • Heritability is the ability of a trait to be passed down. • There is a struggle for survival due to overpopulation and limited resources. • Darwin proposed that adaptations arose over many generations.
VARIATION OVERPRODUCTION ADAPTATION Natural selection explains how evolution can occur. • There are four main principles to the theory of natural selection. • variation • overproduction • adaptation • descent with modification
Natural selection explains how evolution can occur. • There are four main principles to the theory of natural selection. • Variation • overproduction • adaptation • descent with modification • Fitness is the measure of survival ability and ability to produce more offspring.
five digits wrist bone Natural selection acts on existing variation. • Natural selection can act only on traits that already exist. • Structures take on new functions in addition to their original function.
Your Team Members • Kennidra, Anna, Felicia, Faith • Makay, Cole, Alex, Farrah • Haley, Marquasia, Caity, Eric • Tameshia, Whitney, Brittany C., Dhanika • Brittany P., Crystal, Teresa, Nicole • Emily, Drennan, Julia
Your Task • Find out all components on the bottom of the cube. You can only view one side of the cube and everyone can see the top. • You can get information from other teams only if they want to share information with you. • You have to write a short paragraph on what your answer is and why you think it is the correct answer.