Summary: This Commentary provides evidence that oxygen supply capacity in some fishes is optimized for performance at low oxygen, and discusses the implications of this finding for calculations of metabolic index.
Too big to study? The biologging approach to understanding the behavioural energetics of ocean giants
Summary: Increasingly sophisticated animal-borne electronic tags provide a new way of studying the energetics of giant marine vertebrates, for which captive experiments are limited or impossible.
Summary: Snakes are capable of generating propulsion via vertical undulations, which allows them to exploit their environment in 3D and allows more effective use of previously overlooked surfaces in cluttered habitats.
Highlighted Article: Methamphetamine pollution alters fish behavior and habitat preference in freshwater ecosystems.
Dental microwear texture gradients in guinea pigs reveal that material properties of the diet affect chewing behaviour
Summary: Guinea pigs fed plant versus pelleted diets show development of opposing wear gradients along the cheek teeth row; this has implications for diet reconstruction based on dental microwear analysis when only isolated teeth are available.
Summary: The foot and its small muscles make important contributions to ankle function and to full-body movements when landing and jumping.
Summary: Capillary-like vessels are well developed to provide ghost crab skeletal muscles with hemolymph. Aerobic fibers maintain smaller diameters and receive greater hemolymph flow than glycolytic fibers used for locomotion.
Summary: Tags attached to baleen whales demonstrate how thrust power output, drag coefficient and Froude efficiency scale with swimming speed and body length.
Summary: Powered flight might constrain morphology such that certain immunological features are prioritized. Bats show largely similar cell proportions across body mass compared with strong allometric scaling relationships in birds and non-volant mammals.
Evidence for the use of a high-resolution magnetic map by a short-distance migrant, the Alpine newt (Ichthyosaura alpestris)
Summary: Newts derive geographic position over distances of 1–2 km using a twilight sampling strategy to obtain map information that may involve precise measurements of spatial variation in the geomagnetic field.
The role of ligand-gated chloride channels in behavioural alterations at elevated CO2 in a cephalopod
Summary: Ionotropic GABA receptors and other ligand-gated chloride channels may underlie the alterations of some conspecific-directed behaviours at elevated CO2 in a cephalopod.
Summary: Pollen-specialist Andrena vaga bees are highly tuned to 4-oxoisophorone, a typical Salix odorant component, at a very low concentration.
Juvenile hormone affects age polyethism, ovarian status and cuticular hydrocarbon profile in workers of the wasp Polybia occidentalis
Summary: Juvenile hormone, a pleiotropic hormone, regulates three different aspects in the social context of Polybia occidentalis: ovarian activation, behavioral maturation and chemical communication.
Highlighted Article: The energetic mass-specific cost of transport for vertical climbing in humans is negatively correlated with climbing velocity, independent of body mass, and similar to that of other primates.
Proleg retractor muscles in Manduca sexta larvae are segmentally different, suggesting anteroposterior specialization
Summary: The Manduca sexta principal planta retractor muscle is a more complex structure than previously thought, consisting of multiple fibers originating at several sites and showing segmental differences, suggesting anterior–posterior specialization.
Cubam receptor-mediated endocytosis in hindgut-derived pseudoplacenta of a viviparous teleost (Xenotoca eiseni)
Summary: An endocytic pathway is a candidate for nutrient absorption in pseudoplacenta of a viviparous teleost. The trait may have developed from a common intestinal mechanism among vertebrates.
Role of the G protein-coupled receptors GPR84 and GPR119 in the central regulation of food intake in rainbow trout
Summary: The G protein-coupled receptors GPR84 and GPR119 are involved in food intake regulation in fish through their capacity to sense medium-chain fatty acid (GPR84) or N-acylethanolamides/triglyceride-derived molecules (GPR119).
Summary: Thick-billed murres have limited heat tolerance, displaying low evaporative cooling efficiencies and increases in physiological traits associated with heat stress at low air temperatures relative to desert birds.
Elevated cortisol lowers thermal tolerance but results in limited cardiac remodelling in rainbow trout (Oncorhynchus mykiss) experiencing chronic social stress
Summary: Chronic social stress lowers thermal tolerance (measured as CTmax) in rainbow trout. Manipulated cortisol levels show that chronic elevation of cortisol is the cause of lowered CTmax.
Repeat exposure to hypercapnic seawater modifies growth and oxidative status in a tolerant burrowing clam
Summary: Hypercapnic conditions during postlarval development improve physiological performance and oxidative status in Panopea generosa.
Long-term memory of configural learning is enhanced via CREB upregulation by the flavonoid quercetin in Lymnaea stagnalis
Summary: Intermediate-term memory for configural learning is converted to long-term memory following CREB upregulation by quercetin in Lymnaea stagnalis.