Hybridization of the Habitat

Abstract

The rarity of hybrids under natural conditions is discussed. Many biologists encounter them, if at all, only where the habitat has been greatly disturbed. One reason for this is the comparative frequency of back-crosses of the 1st generation hybrids to one or both parents. The hybrid ancestry of such individuals is not apparent. The usual lack of conspicuously different hybrid segregates is imposed by the habitat because the segregating hybrid generations (i.e., everything beyond the F2) consist of individuals each of which requires its own peculiar habitat for optimum development. In other words, the segregating hybrids are confronted with a non-segregating habitat. In places where man has so greatly disturbed natural conditions as to make various new (and less competitive) habitats a greater variety of hybrid segregates may be able to survive. It is concluded that hybrid swarms will usually survive only in "hybridized habitats." While most of the latter result from human intervention, similar conditions have prevailed in pre-human times when new lands were opened up to colonization by diverse floras.