Scaling of Respiratory Variables and the Breathing Pattern in Birds: An Allometric and Phylogenetic Approach

Abstract

Allometric equations can be useful in comparative physiology in a number of ways, not the least of which include assessing whether a particular species deviates from the norm for its size and phylogenetic group with respect to some specific physiological process or determining how differences in design among groups may be reflected in differences in function. The allometric equations for respiratory variables in birds were developed 30 yr ago by Lasiewski and Calder and presented as "preliminary" because they were based on a small number of species. With the expanded data base now available to reconstruct these allometries and the call for taking account of the nonindependence of species in this process through a phylogenetically independent contrasts (PIC) approach, we have developed new allometric equations for respiratory variables in birds using both the traditional and PIC approaches. On the whole, the new equations agree with the old ones with only minor changes in the coefficients, and the primary difference between the traditional and PIC approaches is in the broader confidence intervals given by the latter. We confirm the lower VE/VO2 ratio for birds compared to mammals and observe a common scaling of inspiratory flow and oxygen consumption for birds as has been reported for mammals. Use of allometrics and comparisons among avian groups are also discussed.

Mammalian basal metabolic rate is proportional to body mass2/3

“…This study finds that the BMR of mammals is proportional to M 2/3 , as is the case for birds (20)(21)(22)(23). The relationships presented here fail to account for only 4% of the interspecific and 1% of the interordinal variation in mammalian BMR.…”

Spike firing allometry in avian intrapulmonary chemoreceptors: matching neural code to body size

“…Some birds in our study had closer phylogenetic ties than others (Frappell et al, 2001), so we tested the effect of phylogenetic relatedness using PDAP (Phenotypic Diversity Analysis Programs), version 6.0 (Garland et al, 1993(Garland et al, , 1999Garland and Ives, 2000) running in DOS on a Pentium III based Dell Optiplex GX150 PC. Phylogenetically corrected allometric mass exponents and constants (with their standard errors) calculated with PDAP are reported below.…”

“…This is often explained as biological time (as opposed to clock time) running faster for small animals and slower for large animals. When quantified using the allometric scaling model, ; that is, they scale to the negative 1/4 to 1/3 power of body mass (Brown and West, 2000;Calder, 1996;Frappell et al, 2001;Lindstedt and Calder, 1981;Schmidt-Nielsen, 1984). In the allometric model, y is a biological trait, M b is body mass, a is a constant associated with phylogenetic characteristics, and b is the mass exponent.…”

Applications of Contaminant Fate and Bioaccumulation Models in Assessing Ecological Risks of Chemicals: A Case Study for Gasoline Hydrocarbons

“…Specific parameters for describing breathing rates of mammals and birds in the case study were taken from Frappell et al (18). Details of parameters and equations used are given in Table 3 and the supporting information.…”