The avian bill is a textbook example of how evolution shapes morphology in response to
changing environments. Bills of seed‐specialist finches in particular have been the focus of …

Biological rules describe general morphological, structural and genetic patterns within and
across species. Within these, ecogeographical rules correlate phenotypic variation of …

Ecogeographical rules that associate climate with organismal form and function can reveal
patterns of climatic adaptation. Two rules link animal coloration with climate: Gloger's rule …

During the process of ecological speciation, reproductive isolation results from divergent
natural selection and leads to a positive correlation between genetic divergence and …

Ecogeographical rules, describing common trends in animal form across space and time,
have provided key insights into the primary factors driving species diversity on our planet …

Aim To test whether intra‐and interspecific patterns in body mass along elevational
gradients follow Bergmann's rule for a subset of tropical montane passerines. Location …

Geographic variation in body size has been studied in the context of Bergmann's and Allen's
ecogeographic rules, which relate changes in body and appendage sizes to temperature …

Background The ridges and valleys of the Andes create physical barriers that limit animal
dispersal and cause deterministic local variation in rainfall. This has resulted in physical …

Torrent ducks inhabit fast-flowing rivers in the Andes from sea level to altitudes up to 4500
m. We examined the mitochondrial physiology that facilitates performance over this …

Limits to flight performance at high altitude potentially reflect variable constraints deriving
from the simultaneous challenges of hypobaric, hypodense and cold air. Differences in flight …