Problems and Policy for Species Threatened by Hybridization: The Red Wolf as a Case Study



Hybridization involving rare and endangered species and subspecies may be a concern if it threatens their genetic integrity. The depth of concern depends somewhat on the definition of species and subspecies that is applied and the evolutionary significance of hybridization at different taxonomic levels. The Endangered Species Act does not distinguish among different taxonomic levels, nor does it directly address protection of hybrids. In this paper, we show, using molecular genetic techniques, that red wolves have hybridized extensively with coyotes and gray wolves. Three hypotheses are given for the origin of the red wolf phenotype and we discuss the policy implications of each hypothesis. We argue that if the captive-bred red wolves are descendants of a once distinct species or subspecies they deserve protection even though they are hybrids. However, if they are entirely a hybrid form, their protection and reintroduction should be questioned.


Distinct Species Hybrid Zone Species Concept Hybrid Form Captive Breeding 
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Copyright information

© Elsevier Science Publishers Ltd 1992

Authors and Affiliations

  1. 1.Department of BiologyUniversity of California-Los AngelesLos AngelesUSA

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