Evolucija organizmov se nenehno odvija v odnosu med njimi in okoljem. Zaradi spremenljivosti okolja lahko celo rečemo, da je evolucija edini način preživetja biosfere. Sicer pa daje okolje organizmom priložnost za razmnoževanje in jih hkrati omejuje s končnostjo svojih virov. Med sabo pa vrste v okolju sklepajo povezave v okviru prehranjevalnih verig, pri čemer se marsikdaj srečamo s koevolucijo. Za odnose znotraj vrste predstavlja okolje prostor tekmovanja za preživetje in reprodukcijo. Za evolucijo vrst so pomembni tudi ekosistemi kot emergentni sistemi (sistemi, katerih značilnosti ne moremo zožiti na lastnosti in zakonitosti, ki veljajo za njihove dele oziroma elemente).

Organisms evolve only through interaction between themselves and their environment. Because of ceaseless changes of environment we may say that the evolution is a necessity for the survival of the biosphere. The environment yields an opportunity for the reproduction of organisms and at the same time it restricts them through its limitations. The species in an ecosystem are interconnected through the food chains within which they are often involved in co-evolution. For the intra-species relations the environment represents a place for the competition of its members for life and reproduction. Ecosystems as emergent systems (system with irreducible features and/ or principles) are also very important for the evolution of species.