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Rocky Mountain bighorn ram (Ovis canadensis canadensis) courts an estrous ewe during a cooperative tending relationship. This ram, “Grayballs,” had alpha dominance rank in 1980. Rams at lower ranks sometimes employed alternative mating strategies. See page 526. [John T. Hogg, University of Montana, Missoula, Montana 59812]


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Science. ISSN 0036-8075 (print), 1095-9203 (online)