The effects of humidity on thermoregulatory physiology of a small songbird.

Scholander-Irving curves describe the relationship between ambient temperature and metabolic rate and are fundamental to understanding the energetic demands of homeothermy. However, Scholander-Irving curves are typically measured in dry air, which is not representative of the humidity many organisms experience in nature. Consequently, it is unclear (1) whether Scholander-Irving curves (especially below thermoneutrality) are altered by humidity, given the effects of humidity on thermal properties of air, and (2) whether physiological responses associated with Scholander-Irving curves in the lab reflect organismal performance in humid field conditions.

Adaptive and non-adaptive convergent evolution in feather reflectance of California Channel Islands songbirds.

Convergent evolution is widely regarded as a signature of adaptation. However, testing the adaptive consequences of convergent phenotypes is challenging, making it difficult to exclude non-adaptive explanations for convergence. Here, we combined feather reflectance spectra and phenotypic trajectory analyses with visual and thermoregulatory modelling to test the adaptive significance of dark plumage in songbirds of the California Channel Islands.

Parameterizing mechanistic niche models in biophysical ecology: a review of empirical approaches.

Mechanistic niche models are computational tools developed using biophysical principles to address grand challenges in ecology and evolution, such as the mechanisms that shape the fundamental niche and the adaptive significance of traits. Here, we review the empirical basis of mechanistic niche models in biophysical ecology, which are used to answer a broad array of questions in ecology, evolution and global change biology. We describe the experiments and observations that are frequently used to parameterize these models and how these empirical data are then incorporated into mechanistic niche models to predict performance, growth, survival and reproduction.

Seasonal patterns of dietary partitioning in vertebrates.

Dietary partitioning plays a central role in biological communities, yet the extent of partitioning often varies dramatically over time. Food availability may drive temporal variation in dietary partitioning, but alternative paradigms offer contrasting predictions about its effect. We compiled estimates of dietary overlap between co-occurring vertebrates to test whether partitioning is greater during periods of high or low food abundance.

Performance Trade-Offs and Resource Availability Drive Variation in Reproductive Isolation between Sympatrically Diverging Crossbills.

AbstractTheoretical models indicate that speciation, especially when the scope for gene flow is great (e.g., sympatric speciation), is most likely when strong performance trade-offs coincide with reproduction.

Strong yet incomplete reproductive isolation in is not contradicted by other lines of evidence: A reply to Toews et al.

Toews et al. assert that strong reproductive isolation in is inconsistent with other lines of evidence. Here, we discuss how strong yet incomplete reproductive isolation is consistent with other results from this system.

Character displacement of a learned behaviour and its implications for ecological speciation.

Cultural evolution may accelerate population divergence and speciation, though most support for this hypothesis is restricted to scenarios of allopatric speciation driven by random cultural drift. By contrast, the role of cultural evolution in non-allopatric speciation (i.e.

An Alternative to Adaptation by Sexual Selection: Habitat Choice.

Adaptation in mating signals and preferences has generally been explained by sexual selection. We propose that adaptation in such mating traits might also arise via a non-mutually exclusive process wherein individuals preferentially disperse to habitats where they experience high mating performance. Here we explore the evolutionary implications of this process.

Comment on Van Belleghem et al. 2016: Habitat choice mechanisms in speciation and other forms of diversification.

Several mechanisms of habitat choice can contribute to speciation. Empirical studies of habitat choice mechanisms provide important insights into the relative roles of these mechanisms in speciation. A recent paper by Van Belleghem and colleagues characterizes the mechanistic basis of a component of habitat choice-departure behavior-in two salt marsh beetle ecotypes that inhabit different environments.

Assessing the Potential Contributions of Reduced Immigrant Viability and Fecundity to Reproductive Isolation.

Reduced fitness of immigrants from alternative environments is thought to be an important reproductive isolating barrier. Most studies evaluating the importance of the relative fitness of immigrants to speciation have focused on reduced survival of immigrants (i.e.