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Summary1. It is widely recognized that macroecological patterns are not independent of the evolution of the lineages involved in generating these patterns. While many researchers have begun to evaluate the effect of ancestordescendant relationships on observed patterns using the phylogenetic comparative method, most macroecological studies only utilize the cross-sectional comparative method to 'remove the phylogenetic history', without considering the option of evaluating its effect without removing it. 2. Currently, most researchers use this method without explicitly evaluating three fundamental evolutionary assumptions of the comparative method: (i) that the phylogeny is constructed without error (which implies evaluating phylogenetic uncertainty); (ii) that more closely related species tend to show more similar characters than expected by chance (which implies evaluating the phylogenetic signal) and; (iii) that the model of the characters' evolution effectively recapitulates their history (which implies comparing the fit of several evolutionary models and evaluating the uncertainty of the estimating model parameters). 3. Macroecological studies will benefit from the use of the comparative method to assess the effect of phylogenetic history without removing its effect. The comparative method will also allow for the simultaneous analysis of trait evolution and its impact on diversification rates; it is important to evaluate these processes together because they are not independent. In addition, explicit evaluations of the assumptions of comparative methods using Bayesian inferences will allow researchers to quantify the uncertainty of specific evolutionary hypotheses accounting for observed macroecological patterns. 4. We illustrate the usefulness of the method using the phylogeny of the genus Sebastes (Pisces: Scorpaeniformes), together with data on the body size-latitudinal range relationship to estimate the effect of phylogenetic history on the observed macroecological pattern.

Here, we evaluate the so-called Thorson's rule, which posits that direct-development and larger eggs are favored toward the poles in marine organisms and whose validity been the subject of considerable debate in the literature, combining an expanded phenotypic dataset encompassing 60 species of benthic octopuses with a new molecular phylogeny. Phylogenetic reconstruction shows two clades: clade 1 including species of the families Eledonidae, Megaleledonidae, Bathypolypodidae, and Enteroctopodidae, and clade 2 including species of Octopodidae. Egg size, development mode, and all environmental variables exhibited phylogenetic signal, partly due to differences between the two clades: whereas most species in clade 1 inhabit cold and deep waters, exhibit large eggs and hatchling with holobenthic development, species from clade 2 inhabit tropical-temperate and shallow waters, evolved small eggs, and generally exhibit merobenthic development. Phylogenetic regressions show that egg size exhibits a conspicuous latitudinal cline, and that both egg size and development mode vary with water temperature. Additionally, analyses suggest that egg size is constrained by body size in lineages with holobenthic development. Taken together, results suggest that the variation in egg size and development mode across benthic octopuses is adaptive and associated with water temperature, supporting Thorson's rule in these organisms.