In one species of bird, there are three varieties of feather color. what is this an example of?

The correct answer is -

Genetic diversity.

Explanation:

Genetic diversity can be described as the number of genetic traits or characteristics that are present in the genome (genetic makeup) of a particular species. It enables the population of the species to adapt to changing environmental conditions.

Genetic characteristics vary within a population due to presence of different gene variants, also called alleles.

As per the given information in the question, in one species of bird, there are three varieties of feather color. Thus, it indicates genetic diversity within that species of bird.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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