Issues

Summary: The rapid growth in knowledge of how microbial symbionts may affect their hosts is expanding our view of animal physiology and ecology in profound ways.

Summary: Honeybees exhibit an efficient organization to defend their nest against a variety of intruders. We review the mechanisms of this defensive behaviour and highlight its plasticity at the individual and colony levels.

Summary: A detailed examination of the body and wing kinematics of four hummingbird species in fast escape manoeuvres shows that they change wing trajectory significantly, and escape manoeuvres do not obey the ‘helicopter model’.

Summary: Both neural delays and muscle mechanical power capacity could limit the manoeuvring performance of hummingbirds, and pitch manoeuvres require faster sensorimotor transduction than roll manoeuvres.

Summary: Androgen levels of fixed and plastic alternative reproductive tactics in the snail shell-brooding cichlid Lamprologus callipterus differ and are influenced by specific social and reproductive challenges.

Highlighted Article: Brain gene expression analysis sheds new light on the relationship between instincts and learned behaviors and provides new insights into how the brain's reward system influences social behavior.

Summary: Comparative response profiling of two freshwater mussels, Villosa lienosa and Villosa nebulosa, under acute and chronic heat conditions indicates disparate thermal response mechanisms that may influence their range and survival under predicted global warming.

Summary: Investigation of the effect of antennal mechanosensory stimulation in female crickets walking on a trackball shows that phonotaxis to male calling song is suppressed while the animals explore objects with their antennae.

Summary: Active shortening permitted by a tendon of high physiological compliance not only constrains muscle force generation, but also reduces force summation and accelerates the time course of relaxation.

Highlighted Article: The sandfish S. scincus spends nearly its whole life in fine desert sand. We discovered that it has an aerodynamic filtering system to prevent sand particles from entering the lungs.

Summary: Anurans integrate multiple mechanisms to maintain cardiovascular homeostasis; influences of the baroreflex on lung ventilation in the toad Rhinella schneideri correlate with function of the lymphatic system.

Summary: Undisturbed freshwater turtles, unlike mammals and birds, do not maintain high arterial P_O2 during routine activities. Oxygen levels are highly variable and often increase rather than decline during underwater breath holds.

Highlighted Article: The low energy consumption of Nepalese porters while carrying load cannot be explained by a reduction of their muscular mechanical work.

Summary: Motor activity facilitates the transition from uncertainty to decision making in snails; beneficial effects of physical exercise on cognitive performance in mammals might thus have deep roots in evolution.

Summary: Intraspecific differences in flight-related morphological and physiological variables over an ∼3000 m elevational range indicate aerodynamic constraints on flight performance in parallel with enhanced heart and lung masses to offset hypoxic challenge.

Highlighted Article: Vision is critical for locomotion, but it is poorly understood in relation to locomotor biomechanics in non-human vertebrates. The secondarily diurnal gecko, Rhoptropus afer, shows changes in speed and posture in low light conditions.

Summary: Suction, salivation, chelicerae movements and inactivity at different frequencies over time are the events that occur during blood feeding of Ornithodoros rostratus on their vertebrate hosts.

Summary: Aedes aegypti mothers infected with DENV-2 produce more eggs with a sex ratio skewed towards males, and their daughters do not show a reproductive cost from vertical infections.