That's a tricky question. On most levels, phenotype is unique to each organism. A phenotype of a bacteria is very different from phenotype of e.g. human.
Although, with a bit of cleverness, assuming that bacteria are the most common and the most numerous organisms on Earth, it could be correctly said that bacterial body is the most common phenotype.
Even better, if we took the phenotype as a molecular level of phenotype, it could be said that DNA replicating, to-RNA-transcripting body, body with protein synthesis based on mRNA and ribosomes is the most common phenotype. :)
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This question can be interpreted a few different ways. If you were asking for the answer to a definition then it would be called the wild type, where the changed phenotype is the mutant.
Wild Type
the Phenotype is the direct result of the genotype and the environment...... genotype + environment = Phenotype
The_phenotype_of_a_plant_can_most_easily_be_determined_by
YY is phenotype Yy is not yy is a phenotype
Wild type
the appearance of an organism is it's phenotype
A wild type.
the Phenotype is the direct result of the genotype and the environment...... genotype + environment = Phenotype
Fitness.
The_phenotype_of_a_plant_can_most_easily_be_determined_by
autosomes
genotype or phenotype
YY is phenotype Yy is not yy is a phenotype
Wild type
the appearance of an organism is it's phenotype
Competition between organisms would most likely cause the phenotype frequency in a population that changes each generation.
The phenotype of the organisms. The physical and behavioral traits of the organism.
The phenotype is the physical appearance of an organism. The wild type phenotype is the most common phenotype found in wild populations of that organism. Wild type genes work together to produce the wild type phenotype. Wild type is the standard of reference. Nonstandard phenotypes can be attributed to the action of one or more mutant genes. Descriptions can be reduced to deviations from the standard. The mutant gene responsible for a deviation becomes the center of attention. And a standard of reference minimizes the chance of mistakes in interpreting the results of breeding tests.