03 August 1984
Vol 225, Issue 4661

About The Cover

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]