Seeing the forest for the trees: partitioning ecological and phylogenetic components of Bergmann's rule in European Carnivora

Abstract

Comparative methods have commonly been applied in macroecological research. However, few methods exist to map and analyze phylogenetic variation in geographical space. Here we develop a general analytical framework to partition the phylogenetic and ecological structures of macroecological patterns in geographic space. As an example, we apply the framework to evaluate interspecific patterns of body size geographic variation (Bergmann's rule) in European Carnivora. We model the components of variance attributable to ecological and phylogenetic effects, and to the shared influence of both factors. Spatial patterns in the ecological component are stronger than those in the original body size data. More importantly, the magnitude of intraspecific body size patterns (as measured by the correlation coefficient between body size and latitude) is significantly correlated with the ecological component across species, providing a unified interpretation for Bergmann's rule at multiple levels of biological hierarchy. This approach provides a better understanding of patterns in macroecological traits and allows improved understanding of their underlying ecological and evolutionary mechanisms.

Phylogenetic signal and major ecological shifts in the ecomorphological structure of stream fish in two river basins in Brazil

“…The specific, or ecological, component represents the ancestry-independent variation, which can be attributed to the adaptation of each species to current environmental conditions (Diniz-Filho et al, 2007). Species or assemblages with high values for specific components have different ancestral morphologies/ ecologies (Diniz-Filho et al, 2007).…”

“…Here, we followed Diniz-Filho et al (2009), in which the eigenvectors with significant correlations with the response variable were selected. The 14 fish ecomorphological attributes were used to obtain the scores of the significant principal components, which were then used as the response variables of the regression (adapted from Diniz-Filho et al, 2007). Regression residuals were used to estimate the S component (Diniz-Filho et al, 2009).…”

Exploring patterns in macroecological traits using sequential phylogenetic eigenvector regression

“…En términos teóricos, la relación intrínseca entre talla corporal y diferentes procesos biológicos conlleva a la fuerte estructuración filogenética de esta, puesto que la talla corporal está restringida por dichas relaciones y, consecuentemente, no varía de forma independiente de sus valores ancestrales aún bajo fuertes presiones de selección. Por ejemplo, Diniz-Filho et al (2007, 2009) mostraron que los patrones de adaptación climática relacionados con la regla de Bergmann no pueden ser directamente evaluados considerando únicamente la talla corporal y que es importante desacoplar la variación de este rasgo en sus componentes filogené-tico y específico (utilizando PVR) para detectar su adaptación climá-tica en escalas macroecológicas -esta dificultad podría estar generando parte de la controversia que rodea a dicha regla ecogeográfica. En términos estadísticos, el fuerte patrón filogenético de la talla corporal refuerzan el hecho de que datos comparativos e interespecíficos no deben ser analizados sin considerar dicha estructura filogenética (Freckleton et al 2002).…”

Using phylogenetic clade composition to understand biogeographical variation in functional traits

“…Nevertheless, the distribution of phylogenetic lineages is often neglected in studies associating CWM and the environment. One possible reason is that linking CWM and phylogeny is not straightforward, and we are still searching for a good framework in which to understand how phylogenetic relationships among species affect mean trait variation across metacommunities (Diniz-Filho et al 2007, de Bello et al 2015, Duarte et al 2016, Lawing et al 2016). …”

“…Phylogeny is now indispensable for explaining the composition and diversity of communities (Webb 2002, CavenderBares et al 2009, and for explanation of specieslevel adaptation (Harvey and Pagel 1991), however we still lack a consensus concerning the importance of phylogeny in explaining CWM (Pillar and Duarte 2010, de Bello et al 2015, Lawing et al 2016. One strategy that has been adopted to help resolve this issue involves removing phylogenetic non-independence before calculating the CWM (Diniz-Filho et al 2007, Diniz-Filho et al 2009, Olalla-Tárraga et al 2010. These authors calculated the CWM of the specific component (the S component of a phylogenetic eigenvector regression), allowing exploration of the CWM independent of evolutionary history.…”