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In his book On the Origin of the Species, Charles Darwin described how species change over time. Which of the following is NOT part of his observations that describes the mechanisms of natural selection?

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Many types of traits and features pass along through generations. These characteristics include hair color, eye color and the shape of facial features, like noses and ears. Inherited variation occurs when egg cells divide. Each egg and sperm cell contains approximately half the genetic information necessary for producing individuals. Upon fertilization of the egg, individuals acquire certain traits from parents, and have unique traits and looks.

Inherited variation produces differences in human eye color, such as blue, green and brown. It also creates a difference in skin color in the human population, and determines whether people have ears with lobes or without lobes.

In addition to inherited variation, some differences among people derive from environmental origins. Environmental causes of variation account for differences in cultural norms, behavior and lifestyle. Most people contain a combination of inherited and cultural traits. These traits explain differences in behavior, weight and other variables in very similar individuals, such as twins.
Learn more about Molecular Biology & DNA

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Many types of traits and features pass along through generations. These characteristics include hair color, eye color and the shape of facial features, like noses and ears. Inherited variation occurs when egg cells divide. Each egg and sperm cell contains approximately half the genetic information necessary for producing individuals.

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the definition of struggle for existence

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Struggle for existence definition, the competition in nature among organisms of a population to maintain themselves in a given environment and to survive to reproduce others of their kind. See more.

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explain the concept of relative fitness and its role in adaptive radiation *Describe how selection acts and what factors contribute to the overal...

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Darwin's grand idea of evolution by natural selection is relatively simple but often misunderstood. To find out how it works, imagine a population of beetles:

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Natural Selection - Crash Course Biology #14