Genotypes and Phenotypes

 Genotypes and Phenotypes

How does selection act on the phenotype when its really the genotype that is passed to the next generation?

Phenotype is the physical expression of a trait and genotype is the gene that causes the expression of the trait. The phenotype is very important to survive in an environment and can be one of the many factors that contribute to the overall success of the organism. For example, if we take a look at the anoles from Improbable Destinies we see that the physical expression or phenotype of each anole is what helps them to truly thrive in their niche. The twig anoles have short and stout legs that hold tightly to twigs and branches while hunting prey and hiding from predators. Garman's anole is larger and stronger, being able to easily navigate the tree trunks and upper branches of trees, even being able to consume other, smaller anoles. 


These physical expressions of the genotype are what allows the gene to be successful or not. The genotype goes through mutations and recombination frequently, causing changes big and small. We now know about different types of mutations, beneficial, neutral, and harmful, and how they affect gene expression.

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