Ecotype

Ecotypes are organisms which belong to the same species but possess different phenotypical features as a result of environmental factors such as elevation, climate and predation. Ecotypes can be seen in wide geographical distributions and may eventually lead to speciation.

In evolutionary ecology, an ecotype, sometimes called ecospecies, describes a genetically distinct geographic variety, population, or race within a species, which is genotypically adapted to specific environmental conditions.

Typically, though ecotypes exhibit phenotypic differences (such as in morphology or physiology) stemming from environmental heterogeneity, they are capable of interbreeding with other geographically adjacent ecotypes without loss of fertility or vigor.

An ecotype refers to organisms which belong to the same species but have different phenotypical characteristics as a result of their adaptations to different habitats. Differences between these two groups is attributed to phenotypic plasticity and are too few for them to be termed as wholly different species. Emergence of variants of the same species may occur in the same geographical region where different habitats provide distinct ecological niches for these organisms. Examples of these habitats include meadows, forests, swamps, and sand dunes. Where similar ecological conditions occur in widely separated places, it is possible for a similar ecotype to occur in the separated locations. An ecotype is different from a subspecies, which may exist across a number of different habitats. In animals, ecotypes owe their differing characteristics to the effects of a very local environment which has been hypothesized to lead to speciation through the emergence of reproductive barriers. Therefore, ecotypes have no taxonomic rank.

Ecotypes are closely related to morphs or polymorphisms which is defined as the existence of distinct phenotypes among members of the same species. Another term closely related is genetic polymorphism; and it is when species of the same population display variation in a specific DNA sequence, i.e. as a result of having more than one allele in a gene's locus.. In order to be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (whose members can all potentially interbreed). Polymorphism are maintained in populations of species by natural selection. In fact, Begon, Townsend, and Harper assert that

There is not always clear distinction between local ecotypes and genetic polymorphisms.

The notions "form" and "ecotype" may appear to correspond to a static phenomenon, however; this is not always the case. Evolution occurs continuously both in time and space, so that ecotypes or forms may qualify as distinct species in a few generations. Begon, Townsend, and Harper offer the following analogy:

... the origin of a species, whether allopatric or sympatric, is a process, not an event. For the formation of a new species, like the boiling of an egg, there is some freedom to argue about when it is completed.