vicariance

noun

vi·​car·​i·​ance vī-ˈker-ē-ən(t)s 

və-

: fragmentation of the environment (as by splitting of a tectonic plate) in contrast to dispersal as a factor in promoting biological evolution by division of large populations into isolated subpopulations

called also vicariance biogeography

Word History

First Known Use

1957, in the meaning defined above