Coevolution

[koh-ev-uh-loo-shuh n or, esp. British, -ee-vuh-] /ˌkoʊ ɛv əˈlu ʃən or, esp. British, -i və-/

noun
1.
involving a series of reciprocal changes in two or more noninterbreeding populations that have a close ecological relationship and act as agents of natural selection for each other, as the succession of adaptations of a predator for pursuing and of its prey for fleeing or evading.
/kəʊˌiːvəˈluːʃən/
noun
1.
the evolution of complementary adaptations in two or more species of organisms because of a special relationship that exists between them, as in insect-pollinated plants and their insect pollinators
n.

also co-evolution, 1965, from co- + evolution; supposedly introduced by Paul Ehrlich and Peter Raven in a study of the relationship between caterpillars and plants.
coevolution
(kō’ěv-ə-l’shən)
The evolution of two or more species that interact closely with one another, with each species adapting to changes in the other. The mutually beneficial development of flowering plants and insects such as bees and butterflies that pollinate them is an example of coevolution, as is the mutually antagonistic development of prey and predator species in which defensive adaptations in the one are matched by counteradaptations in the other aimed at neutralizing or overcoming them.

The process that occurs when two species influence each other during evolution. For example, an insect may evolve specialized parts that allow it to feed on a specific flower, whereas the flower evolves to facilitate pollination by that particular insect.