Range and Distribution
Experiments indicate that sometimes ecotypes manifest only when separated by great spatial distances (of the order of 1000 km). This is due to hybridization whereby different but adjacent varieties of the same species (or generally of the same taxonomic rank) interbreed, thus overcoming local selection. However other studies reveal that the opposite may happen, i.e. ecotypes revealing at very small scales (of the order of 10 m), within populations, and despite hybridization.
In ecotypes, it is common for continuous, gradual geographic variation to impose analogous phenotypic and/or genetic variation. This situation is called cline. A well-known example of cline is the skin color gradation in indigenous human populations worldwide, which is related to latitude and amounts of sunlight. But often the distribution of ecotypes is bimodal or multimodal. This means that ecotypes may display two or more distinct and discontinuous phenotypes even within the same population. Such phenomenon may lead to speciation and can occur if conditions in a local environment change dramatically through space or time.
Read more about this topic: Ecotype
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