Ecotype is a specific phenotype of a species that occurs in in a certain environment, ecosystem, only. Usually other species that live in the same ecosystem define the ecotype. As the ecotype may be inherited but rapidly changes when the ecosystem changes, it is assumed that ecotype is an epigenetic phenomenon.
In this graph species 1 shows a different ecotype in ecosystem A and B as it interacts with other species 2+3 and 4+5, respectively.
