How Can a Researcher Determine Whether Variation in a Phenotypic

question 56

Essay

How can a researcher determine whether variation in a phenotypic trait is caused by environmental factors or by genetic differences?

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Definitions:

Limnetic Morph

A type of fish adapted to living in the open water zone of freshwater habitats, distinct from those living near the bottom or shores.

Reproductive Isolating Barriers

Biological features of organisms that prevent species from interbreeding and producing fertile offspring.

Prezygotic

Pertaining to mechanisms that prevent fertilization or successful reproduction between different species before the formation of a zygote.

Postzygotic

Pertaining to the biological and evolutionary processes that occur after the formation of a zygote, particularly those that influence reproductive success and viability.