Genetic variation<span> is essential for </span>natural selection<span> because </span>natural selection can only increase or decrease frequency of alleles that already exist in the population.Genetic variation<span> is caused by: mutation
i pulled this off of the site i got the information from i hope this helps you out if not sorry
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Answer:
The concept predates the term; Plato suggested applying the principles of selective breeding to humans around 400 BC. Early advocates of eugenics in the 19th century regarded it as a way of improving groups of people. In modern usage, the term eugenics has close ties to scientific racism and white supremacism.
Explanation:
B. Habitat Destruction
This is because the wading birds' wetland habitat was destroyed by the housing developers. Since the wetland was drained, their habitat is no longer available to them for nesting or hunting.
Hydrogen, for example, it gives trees inter molecular force.