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Recent work has demonstrated that the relationship between brain and body mass across mammals is curvilinear. Here, the authors demonstrate this curvilinearity across 4679 species, spanning multiple major animal classes. They show that it is caused by systematic changes in allometry within species leading to macroevolutionary patterns.

Phylogenetic statistical analyses, biophysical models and information from the fossil record show that an evolutionary signal of natural selection acted to increase the flight efficiency of pterosaurs over millions of years.

Phylogenetically informed predictions account for phylogenetic relationships among species while predicting unknown trait values. Here, the authors critically compare this approach with equations derived from phylogenetic generalised least squares and ordinary least squares, demonstrating its improved performance across diverse datasets.

Scleractinian corals are important in both shallow and deep ecosystems. Here, the authors use global spatial distribution data with a phylogenetic approach to examine directionality and speed of colonization during depth diversification, finding an offshore-onshore pattern of evolution and that depth dispersion is associated with phenotypic innovations.

The form and function of an organism are often tightly linked, at least in eukaryotes. In contrast, here it is shown using phylogenetic comparative methods that shape and motility are unlinked across a bacterial taxon, allowing increased evolutionary flexibility.

Projections of extinctions of bird species and losses of functional diversity over the next 100 years suggest that even immediate and widespread threat abatement would be insufficient to prevent losses, and targeted recovery programmes must also be implemented to conserve avian diversity.

Analysis of mammalian brain and body mass reveals a curvilinear relationship contrary to assumptions of log-linear power laws. As mammals grow larger, increases in brain mass compared to body mass diminish.

Primates, especially humans, have large brains and this is thought to reflect our level of cognitive complexity or ‘intelligence’. Could this all be down to what we eat?

The authors test for temperature dependency of ecosystem respiration rates across globally distributed eddy covariance sites, revealing consistent temperature thresholds where ecosystem metabolism changes.

Here, a biogeographical model reconstructs ancestral locations of dinosaurs, revealing the spatial mechanisms underpinning their lengthy radiation process over 170 million years: initially rapid, movement slowed towards the time of their extinction.

The Red Queen metaphor has species accumulating small changes to keep up with a continually changing environment, with speciation occurring at a constant rate. This constant-rate claim is now tested against four competing models, using 101 phylogenies of animal, plant and fungal taxa. The results provide a new interpretation of the Red Queen; a view linking speciation to rare stochastic events that cause reproductive isolation.

Bergmann’s Rule predicts larger body sizes in colder climates. Here, the authors examine extinct and extant dinosaurs (birds) and mammaliaforms, finding no evidence of body size variation with latitude in any group, but a small variation with temperature in extant birds.

Phylogenetic data over the past ~150 million years show smaller fish occurred in warmer waters, moved shorter distances at low speed and had low speciation rates. Fish moved faster and evolved quicker under periods of rapid change, with implications for movement and survival under climate change.

Evolutionary change in basal metabolic rate was not coupled with body temperature across endothermic species, although the mechanism by which birds and mammals adapted to colder environments differed.

Thumbs and brains coevolved in primates. Across living and extinct species, longer thumbs predict bigger brains, highlighting the neural cost of dexterity.

Adaptive radiations often follow the evolution of key traits. The mechanism by which a species determines the sex of its offspring has been linked to critical ecological and life-history traits but not to major adaptive radiations. A coevolutionary relationship is now established in 94 amniote species between the sex-determining mechanism and whether a species bears live young or lays eggs. This is used to predict the evolution of genotypic sex determination before the acquisition of live birth in three extinct marine reptiles.