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Authors: Galis F, Van der Sluijs I, Van Dooren TJ, Metz JA, Nussbaumer M
Publications: J Exp Zoolog B Mol Dev Evol 2007;308:119-126
Species: Dogs
Diseases: Longevity
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In most animal taxa, longevity increases with body size across species, as predicted by the oxidative stress theory of aging. In contrast, in within-species comparisons of mammals and especially domestic dogs (e.g. Patronek et al., '97; Michell, '99; Egenvall et al., 2000; Speakman et al., 2003), longevity decreases with body size.We explore two datasets for dogs and find support for a negative relationship between size and longevity if we consider variation across breeds. Within breeds, however, the relationship is not negative and is slightly, but significantly, positive in the larger of the two datasets. The negative across-breed relationship is probably the consequence of short life spans in large breeds. Artificial selection for extremely high growth rates in large breeds appears to have led to developmental diseases that seriously diminish longevity. [Note: Data used in this study were found via a search of the VMDB records for age and animal size (through breed). Records from the NMBC (Natural History Museum Bern) database were used to calculate a length measure.]
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