Evolutionary Biology Concept Question

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Variation in the natural world persists despite genetic drift and directional selection due to several key factors. The Red Queen Hypothesis suggests that organisms must continuously adapt to changing environments, which contributes to ongoing variation. Gene flow also plays a significant role by introducing new genetic material into populations, maintaining diversity. Other explanations include the lack of consistent selection pressure, frequency-dependent selection, where the fitness of a phenotype depends on its frequency in the population, and heterozygous advantage, where individuals with one copy of a gene may have a fitness benefit, as seen in conditions like Sickle-Cell Anemia. Additionally, concepts like symbiogenesis and mutualism highlight the importance of cooperative interactions at the cellular level, further supporting the persistence of variation.
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What are possible explanations as to why variation persists in the natural world despite the effects of genetic drift and directional selection?
 
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This looks like a homework assignment problem.

What explanations have you come up with so far?
 
jedishrfu said:
This looks like a homework assignment problem.

What explanations have you come up with so far?

One explanation I thought was because of the Red Queen Hypothesis -> Fitness Peak is always changing so organisms keep adapting and changing.

Another explanation was Gene Flow

Are either or both of these correct?
 
How do your answers address the variation persists part?
 
Look at symbiogenesis at the cell level … opportunistic and cooperative. Mutualism may be the norm, not the exception.
 
I suggest you research polymorphism. Basically, it could be gene flow, lack of selection pressure, frequency dependent selection (is good when it is the exception, is bad when it is the norm), or heterozygous advantage (if you have 1 copy of the gene it is good, 2 is bad, 0 is bad, such as Sickle-Cell Anemia).
 
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