Character displacement is when similar species habits overlap, and they are in direct competition for food and other vital resources (Brown and Wlison, 1956).
This can be demonstrated through the competition in sympatry and allopatry and the intra- and inter-specific competition between closely related species in the same geographic region.
Brown, W. L., & Wilson, E. O. (1956). Character displacement. Systematic zoology, 5(2), 49-64.