Frontiers in Physiology
Flexible echolocation behavior of fishing bats during natural hunting situations
It has been known for some time that fishing bats use echolocation to detect and classify acoustical cues from insects along and above water surfaces, and also to detect small water-dwelling prey breaking the water surface for a very short time. But comparisons of echolocation behaviour of a single bat species performing prey captures under different conditions remains scarce. In a new study, Kirstin Übernickel and colleagues compared the echolocation and dip performance of the trawling bat Noctilio leporinus in Panamá when reacting to two different types of cues presented at a water surface using ultrasound recordings with synchronized high-speed video.
Results suggest that trawling bats possess the ability to modify their generally rather stereotyped echolocation behavior during approaches within very short reaction times. Capture behavior usually began less than half a second before prey capture, but could also be realized in less than half the time if necessary. The bats were able to react to a cue very fast within approximately 50 ms. In the case of a disappearing cue, the bats probably used spatial memory to dip at the original location after its disappearance. Furthermore, in some failed capture attempts the bats continued to emit calls, likely to achieve fast updates of information for a subsequent capture attempt.
Frontiers in Psychology
Showing positive emotions: A good way of achieving goals at work
How can you promote goal attainment when interacting with others in the workplace? Whether it is to ask your boss for a vacation, or simply to assure a smooth and agreeable cooperation with your colleagues for mutual benefit? In a new study, Elena Wong and colleagues find that it is important to express positive emotions in social situations to achieve goals. They studied 113 employees at different work organizations, whom reported 494 real life social interactions in which they pursued a goal. Participants also reported which emotions they felt and showed in such interactions.
Results show that expressing positive emotions promotes goal attainment, yet, amplifying positive emotions increased goal attainment in interactions only with superiors, but not with colleagues. The authors of the study discuss the importance of hierarchy for detecting, and interpreting, signs of strategic display of positive emotions.
Frontiers in Microbiology
Links between metabolic plasticity and functional redundancy in freshwater bacterioplankton communities
Bacteria play a key role in all aquatic ecosystems functioning. The widespread application of molecular techniques has revealed an unsuspected level of genetic diversity within aquatic prokaryotic communities. These communities are extremely sensitive and reactive to changes in environmental conditions.. Metabolic plasticity and functional redundancy are fundamental properties of microbial communities, yet, their actual quantification has been elusive.
In this study, Jérôme Comte and colleagues present an experimental framework in which they simultaneously quantify metabolic plasticity and functional redundancy in freshwater bacterioplankton communities, and explore connections that may exist between them. Results show that metabolic plasticity is an intrinsic property of bacterial communities, whereas the expression of functional redundancy appears to be more dependent on environmental factors. Furthermore, there was a strong positive relationship between them, suggesting no trade-offs between these community attributes but rather a possible co-selection. This study has important conceptual and practical implications on how we view and assess the links between composition and the functioning of microbial communities.