Gene expression comparisons between captive and wild shrew brains reveal captivity effects.

Compared with their free-ranging counterparts, wild animals in captivity experience different conditions with lasting physiological and behavioural effects. Although shifts in gene expression are expected to occur upstream of these phenotypes, we found no previous gene expression comparisons of captive versus free-ranging mammals. We assessed gene expression profiles of three brain regions (cortex, olfactory bulb and hippocampus) of wild shrews () compared with shrews kept in captivity for two months and undertook sample dropout to examine robustness given limited sample sizes.

Bats surf storm fronts during spring migration.

Long-distance migration, common in passerine birds, is rare and poorly studied in bats. Piloting a 1.2-gram IoT (Internet of Things) tag with onboard processing, we tracked the daily location, temperature, and activity of female common noctules () during spring migration across central Europe up to 1116 kilometers.

Consistent long-distance foraging flights across years and seasons at colony level in a neotropical bat.

All foraging animals face a trade-off: how much time should they invest in exploitation of known resources versus exploration to discover new resources? For group-living central place foragers, this balance is challenging. Due to the nature of their movement patterns, exploration and exploitation are often mutually exclusive, while the availability of social information may discourage individuals from exploring. To examine these trade-offs, we GPS-tracked groups of greater spear-nosed bats () from three colonies on Isla Colón, Panamá.

Time synchronisation for millisecond-precision on bio-loggers.

Time-synchronised data streams from bio-loggers are becoming increasingly important for analysing and interpreting intricate animal behaviour including split-second decision making, group dynamics, and collective responses to environmental conditions. With the increased use of AI-based approaches for behaviour classification, time synchronisation between recording systems is becoming an essential challenge. Current solutions in bio-logging rely on manually removing time errors during post processing, which is complex and typically does not achieve sub-second timing accuracies.

Heart rate monitoring reveals differential seasonal energetic trade-offs in male noctule bats.

Understanding how animals meet their daily energy requirements is critical in our rapidly changing world. Small organisms with high metabolic rates can conserve stored energy when food availability is low or increase energy intake when energetic requirements are high, but how they balance this in the wild remains largely unknown. Using miniaturized heart rate transmitters, we continuously quantified energy expenditure, torpor use and foraging behaviour of free-ranging male bats () in spring and summer.

Seasonal shifts in insect ephemerality drive bat foraging effort.

Animal foraging is fundamentally shaped by food distribution and availability. However, the quantification of spatiotemporal food distribution is rare but crucial to explain variation in foraging behavior among species, populations, or individuals. Clumped but ephemeral food sources enable rapid energy intake but require increased effort to find, can generate variable foraging success, and force animals to forage more efficiently.

High temporal resolution data reveal low bat and insect activity over managed meadows in central Europe.

Increasing agriculture and pesticide use have led to declines in insect populations and biodiversity worldwide. In addition to insect diversity, it is also important to consider insect abundance, due to the importance of insects as food for species at higher trophic levels such as bats. We monitored spatiotemporal variation in abundance of nocturnal flying insects over meadows, a common open landscape structure in central Europe, and correlated it with bat feeding activity.

Robust evidence for bats as reservoir hosts is lacking in most African virus studies: a review and call to optimize sampling and conserve bats.

Africa experiences frequent emerging disease outbreaks among humans, with bats often proposed as zoonotic pathogen hosts. We comprehensively reviewed virus-bat findings from papers published between 1978 and 2020 to evaluate the evidence that African bats are reservoir and/or bridging hosts for viruses that cause human disease. We present data from 162 papers (of 1322) with original findings on (1) numbers and species of bats sampled across bat families and the continent, (2) how bats were selected for study inclusion, (3) if bats were terminally sampled, (4) what types of ecological data, if any, were recorded and (5) which viruses were detected and with what methodology.

Domestication effect of reduced brain size is reverted when mink become feral.

A typical consequence of breeding animal species for domestication is a reduction in relative brain size. When domesticated animals escape from captivity and establish feral populations, the larger brain of the wild phenotype is usually not regained. In the American mink (), we found an exception to this rule.

Contrasting Torpor Use by Reproductive Male Common Noctule Bats in the Laboratory and in the Field.

Metabolic processes of animals are often studied in controlled laboratory settings. However, these laboratory settings often do not reflect the animals' natural environment. Thus, results of metabolic measurements from laboratory studies must be cautiously applied to free-ranging animals.

Histological and MRI brain atlas of the common shrew, , with brain region-specific gene expression profiles.

The common shrew, , is a small mammal of growing interest in neuroscience research, as it exhibits dramatic and reversible seasonal changes in individual brain size and organization (a process known as Dehnel's phenomenon). Despite decades of studies on this system, the mechanisms behind the structural changes during Dehnel's phenomenon are not yet understood. To resolve these questions and foster research on this unique species, we present the first combined histological, magnetic resonance imaging (MRI), and transcriptomic atlas of the common shrew brain.

A multi-species evaluation of digital wildlife monitoring using the Sigfox IoT network.

Bio-telemetry from small tags attached to animals is one of the principal methods for studying the ecology and behaviour of wildlife. The field has constantly evolved over the last 80 years as technological improvement enabled a diversity of sensors to be integrated into the tags (e.g.

Roost making in bats.

Structures created by animals can serve many purposes. Spiders weave intricate webs to trap prey; beavers engineer complex networks of dams to alter waterways; male bower birds construct and decorate elaborate bowers to attract mates. Animal architecture ranges widely in function, but by far the most common use is shelter.

Fifty years of data show the effects of climate on overall skull size and the extent of seasonal reversible skull size changes (Dehnel's phenomenon) in the common shrew.

Global climate change affects many aspects of biology and has been shown to cause body size changes in animals. However, suitable datasets allowing the analysis of long-term relationships between body size, climate, and its effects are rare. The size of the skull is often used as a proxy for overall body size.

Winter conditions, not resource availability alone, may drive reversible seasonal skull size changes in moles.

Seasonal changes in the environment can lead to astonishing adaptations. A few small mammals with exceptionally high metabolisms have evolved a particularly extreme strategy: they shrink before winter and regrow in spring, including changes of greater than 20% in skull and brain size. Whether this process is an adaptation to seasonal climates, resource availability or both remains unclear.

Flexible energy-saving strategies in female temperate-zone bats.

Torpor is characterized by an extreme reduction in metabolism and a common energy-saving strategy of heterothermic animals. Torpor is often associated with cold temperatures, but in the last decades, more diverse and flexible forms of torpor have been described. For example, tropical bat species maintain a low metabolism and heart rate at high ambient and body temperatures.

A conceptual framework to predict social information use based on food ephemerality and individual resource requirements.

Environmental variability poses a range of challenges to foraging animals trying to meet their energetic needs. Where food patches are unpredictable but shareable, animals can use social information to locate patches more efficiently or reliably. However, resource unpredictability can be heterogeneous and complex.

Micro-sized open-source and low-cost GPS loggers below 1 g minimise the impact on animals while collecting thousands of fixes.

GPS-enabled loggers have been proven as valuable tools for monitoring and understanding animal movement, behaviour and ecology. While the importance of recording accurate location estimates is well established, deployment on many, especially small species, has been limited by logger mass and cost. We developed an open-source and low-cost 0.

Dehnel's phenomenon.

Lázaro and Dechmann explain how some mammals that live through harsh winters exhibit seasonal shrinkage of the brain and skull, a process called Dehnel's phenomenon, which helps to spare energy during times of food shortage and high energetic demands.

Geographic patterns in seasonal changes of body mass, skull, and brain size of common shrews.

Some small mammals exhibit Dehnel's Phenomenon, a drastic decrease in body mass, braincase, and brain size from summer to winter, followed by a regrowth in spring. This is accompanied by a re-organization of the brain and changes in other organs. The evolutionary link between these changes and seasonality remains unclear, although the intensity of change varies between locations as the phenomenon is thought to lead to energy savings during winter.

DNA methylation predicts age and provides insight into exceptional longevity of bats.

Exceptionally long-lived species, including many bats, rarely show overt signs of aging, making it difficult to determine why species differ in lifespan. Here, we use DNA methylation (DNAm) profiles from 712 known-age bats, representing 26 species, to identify epigenetic changes associated with age and longevity. We demonstrate that DNAm accurately predicts chronological age.