Issues

Summary: We propose that the role of 5-HT in modulating invertebrate aggression is more nuanced than previously appreciated; there is evidence for distinct roles of 5-HT receptor subtypes in stalk-eyed flies, similar to the situation in vertebrates.

Highlighted Article: Analyses of 14 fish and cetaceans during breaches indicates that the universal upper boundary of power production is ∼200 W kg⁻¹ muscle, which matches maximum power recorded by animals under any other circumstances.

Summary: Muscles lose torque potential when activated with their agonistic group and this deficit is not associated with smaller moment arms, changes in inter-muscular pressure or inter-muscular force transfer.

Summary: Female mice carrying a selfish genetic element have a longer lifespan; these females have lower metabolic rates as they increase in size, which may arise through gene expression differences in the liver.

Summary: A new method for estimating the spatial and optical resolution of compound eyes, using the 3D micro-CT images of preserved animals.

Summary: Muscle response to rapid, identical strain perturbations is history dependent, but is captured by a viscoelastic model with memory; the data and model show that the muscle perturbation response depends on locomotor frequency.

Summary: Experimental increases in glucocorticoids in breeding female North American red squirrels affects offspring postnatal growth but not levels of oxidative damage and antioxidants or telomere lengths.

Summary: Visual input appears not to be necessary to develop well-focused eyes in diverse arthropods, including camera-type eyes of beetle larvae and spiders, and compound eyes in flies.

Summary: Experience acquired during adulthood changes the morphology, physiology and behavioral output of the olfactory system in the honey bee.

Summary: Measurements of the costs of tonal sound production in bottlenose dolphins indicate that whistle communication is very cheap.

Summary: Perineuronal net and parvalbumin comparisons in blackbird species with contrast in early exposure to song tutors reveals a similar pattern in song learning nuclei but not in a song production nucleus.

Highlighted Article: Male flower beetles have large hind legs that they use to grasp females securely during mating, acting like a vice grip; these legs do not enhance performance during take-off relative to females.

Summary: Reduced performance of aphids infected with a common facultative endosymbiont on poor quality plants may be explained by changes in aphid probing behaviour and decreased phloem sap ingestion.

Summary: Peripheral enzymes are primarily responsible for enzymatic modulation of the glucocorticoid stress response in songbirds.

Highlighted Article: The temporal resolution of vision differs between raptor species, with falcons having higher flicker fusion frequency than hawks.