Meeting Abstract

53.1  Monday, Jan. 5  Phylogenetic Analysis of Mammalian Maximal Oxygen Consumption DLUGOSZ, EM*; CHAPPELL, MA; MEEK, TH; SZAFRANSKA, P; ZUB, K; KONARZEWSKI, M; JONES, JH; BICUDO, E; GARLAND, T, Jr.; University of California, Riverside; University of California, Riverside; University of California, Riverside; Mammal Research Institute, Polish Academy of Sciences; Mammal Research Institute, Polish Academy of Sciences; Mammal Research Institute, Polish Academy of Sciences; University of Bialystok, Poland; University of California, Davis; University of Sao Paolo, Brazil; University of California, Riverside edlug001@ucr.edu

We compiled data from the literature on maximum oxygen consumption during forced exercise (VO₂max), and also included new measurements on ~20 species of small mammals tested in enclosed running wheel respirometers, and on two large rodents, agoutis and capybaras, tested on treadmills. We used both conventional and phylogenetically informed statistics to analyze if VO₂max varied in relation to domestication or measurement method. We used ln likelihood ratio tests and the Akaike Information Criterion (AIC) to compare candidate models. We found no evidence for systematic differences between wheel- versus treadmill-elicited VO₂max in small mammals or between domesticated and wild animals. Considering all 73 "species" (including subspecies or species populations within species), both log₁₀ body mass and residual log₁₀ VO₂max showed highly significant phylogenetic signal (P<0.001). Conventional (non-phylogenetic) analysis indicated an allometric scaling exponent of 0.857 (95% confidence interval 0.823-0.890). The best-fitting model, which separated nine clades and allowed transformation of the phylogenetic branch lengths under an Ornstein-Uhlenbeck model of residual variation, yielded a lower slope (0.747<0.810<0.873). NSF IOB-0543429