Relative Heart Size in Alaskan Tetraonidae

• Published in: The Auk
• Main Author: Weeden, Robert B.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 1979
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Lagopus mutus; rock ptarmigan
• Online Access: http://dx.doi.org/10.1093/auk/96.2.306; http://academic.oup.com/auk/article-pdf/96/2/306/32910565/auk0306.pdf

Abstract Heart:body size ratios were measured in over 1,900 specimens of seven species of Alaskan Tetraonidae. Blue Grouse (Dendragapus obscurus) and Ruffed Grouse (Bonasa umbellus) have hearts averaging only 0.4 to 0.5% of body weight. At the other extreme, Rock Ptarmigan (Lagopus mutus) have hearts averaging 2.0% of body weight. Between these extremes are White-tailed Ptarmigan (L. leucurus), 1.1%; Spruce Grouse (Canachites canadensis), 1.2%; Sharp-tailed Grouse (Pedioecetes phasianellus), 1.4%; and Willow Ptarmigan (L. lagopus), 1.4%. Intraspecific variations related to sex, age, body size, season, and locality were found in some but not all species. The members of this family seem to have evolved diverse strategies for meeting cardiovascular requirements, and heart size alone does not reveal the nature of these systems.