Socio-economic variables improve accuracy and change spatial predictions in species distribution models.

In an era marked by increasing anthropogenic pressure, understanding the relations between human activities and wildlife is crucial for understanding ecological patterns, effective conservation, and management strategies. Here, we explore the potential and usefulness of socio-economic variables in species distribution modelling (SDM), focusing on their impact on the occurrence of wild mammals in Poland. Beyond the environmental factors commonly considered in SDM, like land-use, the study tests the importance of socio-economic characteristics of local human societies, such as age, income, working sector, gender, education, and village characteristics for explaining distribution of diverse mammalian groups, including carnivores, ungulates, rodents, soricids, and bats. The study revealed that incorporating socio-economic variables enhances the predictive power for >60 % of species and overall for most groups, with the exception being carnivores. For all the species combined, among the 10 predictors with highest predictive power, 6 belong to socio-economic group, while for specific species groups, socio-economic variables had similar predictive power as environmental variables. Furthermore, spatial predictions of species occurrence underwent changes when socio-economic variables were included in the model, resulting in a substantial mismatch in spatial predictions of species occurrence between environment-only models and models containing socio-economic variables. We conclude that socio-economic data has potential as useful predictors which increase prediction accuracy of wildlife occurrence and recommend its wider usage. Further, to our knowledge this is a first study on such a big scale for terrestrial mammals which evaluates performance based on presence or absence of socio-economic predictors in the model. We recognise the need for a more comprehensive approach in SDMs and that bridging the gap between human socio-economic dynamics and ecological processes may contribute to the understanding of the factors influencing biodiversity.

Mating without intromission in a bat.

Copulatory behaviours stand as cornerstones of sexual selection, yet they remain mysterious in many species. Because of their nocturnal and elusive lifestyle, the copulatory behaviours of bats have been mostly overlooked1. Several aspects of bat reproduction differ from other mammals (e.g. prolonged sperm storage2, delayed development3). Here, we show that in serotine bats (Eptesicus serotinus) the penis is used as a 'copulatory arm' rather than an intromittent organ, revealing a novel copulatory behaviour in mammals.

Predictors of proarrhythmic effect in heart failure patients after 9-week hybrid comprehensive telerehabilitation and their influence on cardiovascular mortality in long-term follow-up: Subanalysis of the TELEREH-HF randomized clinical trial.

BACKGROUND: Regular exercise training is beneficial in heart failure (HF) patients. However, its potential proarrhythmic effect is possible but has not been sufficiently investigated. OBJECTIVE: To identify patients at risk for proarrhythmic effect after the 9-week of hybrid comprehensive telerehabilitation (HCTR) program vs the 9-week of usual care (UC) and to investigate its predictors and impact on cardiovascular mortality based on data from the TELEREH-HF RCT. METHODS: Proarrhythmic effect, strictly defined on the basis of available standards was evaluated by comparing 24-h Holter ECG before and after 9-week of HCTR or UC of 773 HF patients (The New York Heart Association class I-III, left ventricular ejection fraction ≤40%). RESULTS: The proarrhytmic effect was found in 78 (20.4%) and in 61 (15.6%) patients in the HCTR and UC group respectively, and the difference between groups was not statistically significant (p = 0.081). However, univariate analysis identified several statistically significant predictors of proarrhythmia in HCTR only vs the UC group. After a multivariate analysis ischaemic aetiology of HF (OR = 2.27, p = 0.008), peak oxygen consumption at baseline <14 ml/kg/min (OR = 2.03, p = 0.012) and level of N-terminal-pro B-type natriuretic peptide (NT-proBNP) in the first and the second tercile (OR = 1.85, p = 0.043) were identified to be independent predictors of proarrhytmic effect of exercise training among the HF patients in HCTR group only. CONSLUSIONS: Patients who underwent a 9-week HCTR were not at a higher risk of proarrhythmic effect after its completion compared to UC. However, predictors of proarrhythmia such as ischemic aetiology of HF, poor physical capacity, lower NT-proBNP level were discovered in the HCTR group only, yet it does not cause a significant risk of cardiovascular mortality including sudden cardiac death in long-term follow-up.

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. We investigated whether bats (Nyctalus noctula) from the cooler temperate European regions also show this form of torpor with metabolic inhibition at high body temperatures, and whether this would be as pronounced in reproductive as in non-reproductive bats. We simultaneously measured metabolic rate, heart rate, and skin temperature in non-reproductive and pregnant females at a range of ambient temperatures. We found that they can decouple metabolic rate and heart rate from body temperature: they maintained an extremely low metabolism and heart rate when exposed to ambient temperatures changing from 0 to 32.5 °C, irrespective of reproductive status. When we simulated natural temperature conditions, all non-reproductive bats used torpor throughout the experiment. Pregnant bats used variable strategies from torpor, to maintaining normothermy, or a combination of both. Even a short torpor bout during the day saved up to 33% of the bats' total energy expenditure. Especially at higher temperatures, heart rate was a much better predictor of metabolic rate than skin temperature. We suggest that the capability to flexibly save energy across a range of ambient temperatures within and between reproductive states may be an important ability of these bats and possibly other temperate-zone heterotherms.

Antiarrhythmic effect of 9-week hybrid comprehensive telerehabilitation and its influence on cardiovascular mortality in long-term follow-up - subanalysis of the TELEREHabilitation in Heart Failure Patients randomized clinical trial.

Introduction: Cardiac rehabilitation is a component of heart failure (HF) management, but its effect on ventricular arrhythmias is not well understood. We analyzed the antiarrhythmic effect of a 9-week hybrid comprehensive telerehabilitation (HCTR) program and its influence on long-term cardiovascular mortality in HF patients taken from the TELEREHabilitation in Heart Failure Patients (TELEREH-HF) trial. Material and methods: We evaluated the presence of non-sustained ventricular tachycardia (nsVT) and frequent premature ventricular complexes ≥ 10 beats/hour (PVCs ≥ 10) in 24-hour ECG monitoring at baseline and after 9-week HCTR or usual care (UC) of 773 HF patients (NYHA I-III, LVEF ≤ 40%). Functional response for HCTR was assessed by changes - delta (Δ) - in peak oxygen consumption (pVO2) as a result of comparing pVO2 from the beginning and the end of the program. Results: Among 143 patients with nsVT, arrhythmia subsided in 30.8% after HCTR. Similarly, among 165 patients randomized to UC who had nsVT 34.5% did not show it after 9 weeks (p = 0.481). There was no significant difference in the decrease in PVC ≥ 10 over 9 weeks between randomization arms (14.9% vs. 17.8%, respectively p = 0.410). Functional response for HCTR in ΔpVO2 > 2.0 ml/kg/min did not affect occurrence of arrhythmias. Multivariable analysis did not identify HCTR as an independent factor determining improvement of nsVT or PVCs ≥ 10. However, only in the HCTR group, the achievement of the antiarrhythmic effect significantly reduced the cardiovascular mortality in 2-year follow-up (p < 0.001). Conclusions: Significant improvement in physical capacity after 9 weeks of HCTR did not correlate with the antiarrhythmic effect in terms of incidence of nsVT or PVCs ≥ 10. An antiarrhythmic effect after the 9-week HCTR affected long-term cardiovascular mortality in HF patients.

Energy allocation shifts from sperm production to self-maintenance at low temperatures in male bats.

The ability of animals to produce endogenous heat provides a buffer against environmental changes but also incurs high energetic costs. Especially small endothermic mammals have high energy demands. Some temperate-zone species (heterotherms) regularly use torpor, which slows down their entire metabolism but also potentially delays reproduction, to compensate for this. We used a unique experimental approach to test the consequences of extended low and high ambient temperatures on the trade-off in energy allocation to body mass maintenance, thermoregulation effort and seasonal sexual maturation in temperate zone male bats. We showed that long exposure to low ambient temperature shifts energy allocation away from sexual maturation to self-maintenance and results in a delay of sperm maturation by as much as an entire month. This effect was partially buffered by higher body mass. Heavier bats were able to afford more intensive thermoregulation and consequently speed up maturation. Interestingly, bats at constant high temperatures avoided deep torpor and matured faster than those at low temperatures, but sperm production was also slower than under natural conditions. Our results show that not only low, but also constant high ambient temperatures are detrimental during seasonal sexual maturation and the trade-off between investing into self-maintenance and fitness is a finely tuned compromise.

Food restriction delays seasonal sexual maturation but does not increase torpor use in male bats.

Balancing energy budgets can be challenging, especially in periods of food shortage, adverse weather conditions and increased energy demand due to reproduction. Bats have particularly high energy demands compared to other mammals and regularly use torpor to save energy. However, while torpor limits energy expenditure, it can also downregulate important processes, such as sperm production. This constraint could result in a trade-off between energy saving and future reproductive capacity. We mimicked harsh conditions by restricting food and tested the effect on changes in body mass, torpor use and seasonal sexual maturation in male parti-coloured bats (Vespertilio murinus). Food-restricted individuals managed to maintain their initial body mass, while in well-fed males, mass increased. Interestingly, despite large differences in food availability, there were only small differences in torpor patterns. However, well-fed males reached sexual maturity up to half a month earlier. Our results thus reveal a complex trade-off in resource allocation; independent of resource availability, males maintain a similar thermoregulation strategy and favour fast sexual maturation, but limited resources and low body mass moderate this latter process.

Penis size and sperm quality, are all bats grey in the dark?

Penises play a key role in sperm transport and in stimulating female genitals. This should impact post-copulatory competition, and expose penis characteristics to sexual selective pressures. Studies of male genitalia have repeatedly reported negative static allometries, which mean that, within species, large males have disproportionally small genitals when compared with smaller individuals. Males of some sperm-storing bat species may stand as an exception to such a pattern by arousing from hibernation to copulate with torpid females. The selection for large penises might take place, if a long organ provides advantages during post-copulatory competition and/or if females have evolved mechanisms allowing the choice of sire, relying on characters other than pre-copulatory traits (e.g., penis size). In this study, we measured dimensions of the erected penis in 4 sperm-storing bat species. Furthermore, we collected sperm and evaluated the link between penis dimensions and sperm velocity. Our results revealed steep allometric slopes of the erected penis length in Barbastella barbastellus and an inverse allometry of penis head width in Myotis nattereri. More detailed studies of copulatory behavior are urgently needed to explain the range of observed scaling relations. Furthermore, penis head width correlates with sperm velocity in Plecotus auritus. For this last species, we propose that penis shape might act as a marker of male fertility.