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Keywords: distribution; ecological niche; Montifringilla nivalis; mountains; seasonality; snowfinch EN distribution ecological niche Montifringilla nivalis mountains seasonality snowfinch 1 5 5 10/07/22 20220901 NES 220901 Linking organism distribution to climate is key to understanding factors determining species occurrence and evaluating the potential impacts of ongoing climate change. Insufficient considerations of seasonality, data selection and validation lead to biased species-climate relationships in mountain birds However, we are convinced that the reason for such a finding is not an effective niche expansion in the species, but a question of methods - the inclusion of non-representative occurrence records in the analyses of the species' thermal niche -, neglecting crucial facts about the species' ecology. According to the authors, such a wider niche should be related to a "dramatic niche evolution event", leading to a niche expansion dated perhaps 2.6 mya ago, which allowed this species to occupy warmer areas in the western Palearctic, such as southern Europe. [Extracted from the article]

The article presents a study on the breeding output and quality of chicks in the first and replacement clutches in the Eagle Owl Bubo bubo. The researchers collected chick measurements and blood samples when nestlings were about 30 to 35 days old. They also subjected the dependent variable nesting attempt to a generalized linear mixed model (GLMM) analysis assuming binomial error structure. They found that replacement clutches are important on the fecundity of big long-lived species like the Eagle Owl.

In endotherm animals, several traits are related to climate. For example, Bergmann's rule predicts a decrease in body size within species and across closely related species with increasing temperature, whereas Gloger's rule states that birds and mammals should be darker in humid and warm environments compared to colder and drier areas. However, it is still not clear whether ecotypic responses to variation in the local environment can also apply to morphological and colouration changes through time in response to climate change. We present a 100-year-long time series on morphological and melanin-based colours of snowfinch (325 Montifringilla, 92 Pyrgilauda and 30 Onychostruthus) museum specimens. Here we show that the tarsus length of the species has decreased and the saturation of the melanin-based colour has increased, which was correlated with the increase of temperature and precipitations. As ecotypic variations are tightly linked to individual behavioural and physiological responses to environmental variations, differently sized and coloured individuals are expected to be differently penalized by global changes. This study opens the pertinent question about whether ecotypic responses can enhance population persistence in the context of global change. [ABSTRACT FROM AUTHOR]

Many animals make behavioural changes to cope with winter conditions, being gregariousness a common strategy. Several factors have been invoked to explain why gregariousness may evolve during winter, with individuals coming together and separating as they trade off the different costs and benefits of living in groups. These trade-offs may, however, change over space and time as a response to varying environmental conditions. Despite its importance, little is known about the factors triggering gregarious behaviour during winter and its change in response to variation in weather conditions is poorly documented. Here, we aimed at quantifying largescale patterns in wintering associations over 23 years of the white-winged snowfinch Montifringilla nivalis nivalis. We found that individuals gather in larger groups at sites with harsh wintering conditions. Individuals at colder sites reunite later and separate earlier in the season than at warmer sites. However, the magnitude and phenology of wintering associations are ruled by changes in weather conditions. When the temperature increased or the levels of precipitation decreased, group size substantially decreased, and individuals stayed united in groups for a shorter time. These results shed light on factors driving gregariousness and points to shifting winter climate as an important factor influencing this behaviour. [ABSTRACT FROM AUTHOR]

The rather limited human ability to understand animal vision and visual signalling has frequently clouded our expectations concerning the visual abilities of other animals. But there are multiple reasons to suspect that visual signalling is more widely employed by animals than previously thought. Because visibility of visual marks depends on the background in which they are seen, species spending most of their time living in dark conditions (e.g., in forests and/or having crepuscular and nocturnal habits) may rely on bright signals to enhance visual display. Here, as a result of experimental manipulations, we present, for the first time ever, evidence supporting the use of a new channel of intraspecific communication by a mammal species, i.e., brown bear Ursus arctos adult males relying on visual marks during mating. Bear reactions to our manipulation suggest that visual signalling could represent a widely overlooked mechanism in mammal communication, which may be more broadly employed than was previously thought. [ABSTRACT FROM AUTHOR]