Is the relationship between population density and body size consistent across independent studies? A meta-analytical study approach
Carregando...
Data
2001-02-28
Título da Revista
ISSN da Revista
Título de Volume
Editor
Instituto Internacional de Ecologia
Resumo
The Energetic Equivalence Rule (EER) is a controversial issue in ecology. This rule states that the
amount of energy that each species uses per unit of area is independent of its body size. Here, we
perform a meta-analytical procedure to combine and compare the slopes of population density and
body size relationships across independent studies of mammals and birds. We then compared a distribution
of 50,000 bootstrap combined slopes with the expected slope (b = –0.75) under the EER.
The combined slopes obtained for mammals and birds separately were –0.755 and –0.321, respectively.
The homogeneity hypothesis (i. e. within studies the slopes differ by no more than would be
expected due sampling variation) was rejected in both cases. So, EER cannot be supported since the
use of an exponent of –0.75 is, in fact, an oversimplification. Significant heterogeneity of slopes within
each group (mammals and birds) is an indicator of inferential problems related with variation in body
size, spatial scale, the regression model adopted and phylogenetic relationships among species. So,
we consider that questions regarding the estimation and validity of slopes is the next challenge of
density-body size relationship studies.
Descrição
Palavras-chave
Meta-analysis, Energetic equivalence rule, Mammals, Birds
Citação
BINI, L. M.; COELHO, A. S. G.; DINIZ FILHO, J. A. F. Is the relationship between population density and body size consistent across independent studies? A meta-analytical study approach. Revista Brasileira de Biologia, São Carlos, v. 61, n.1, p. 1-6, Feb. 2001.