intergradation

[ in-ter-grey-dey-shuh n ]

/ ˌɪn tər greɪˈdeɪ ʃən /

the act or process of intergrading or the state of being intergraded.

an evolutionary process by which different species of organisms tend to merge through a series of intermediate stages or grades.

Origin of intergradation

First recorded in 1870–75; inter- + gradation

in·ter·gra·da·tion·al, adjective

Consequently it is unlikely that intergradation with other populations could exist at the present time.

Comments on the Taxonomy and Geographic Distribution of Some North American Rodents |E. Raymond Hall
Intergradation with neomexicana is suggested by one specimen, no. 7936, Univ.

American Weasels |E. Raymond Hall
Details of one such instance of intergradation are given in the account of Mustela frenata spadix.

American Weasels |E. Raymond Hall
Intergradation is noted with Zapus hudsonius pallidus and is discussed in the account of that subspecies.

North American Jumping Mice (Genus Zapus) |Philip H. Krutzsch

Probably this greater breadth is the result of intergradation with M. f. frenata to the westward.

American Weasels |E. Raymond Hall