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Wielkie przetasowanie – kto rządzi ziemią, ten rządzi światem. Recenzja książki Michaela Albertusa, Land Power: Who Has It, Who Doesn’t, and How That Determines the Fate of Societies
Recenzja książki Michaela Albertusa, Land Power: Who Has It, Who Doesn’t, and How That Determines the Fate of Societies,Basic Books, London 2025, ss. 336.
Stork’s Nest - Additional Load on the Supporting Structure of the Low Voltage Power Line
The article presents loading issues of the LV power line supporting structure, with white stork’s nest resting on top of the construction. Technical aspects are presented, which are related to the additional load on the pole resulting from the wind pressure acting on the stork’s nest and the nest mass itself. At present, the data on stork’s nest mass is available and we may develop a model load based on this data.
Intersexual patterns of the digestive tract and body size are opposed in a large bird
AbstractThe appropriate structure of the digestive tract is crucial for individual adaptation to ecological conditions. In birds, the length of the small intestine, responsible for food absorption, is generally believed to be positively correlated with body size. In this study, we investigated the variation in small intestine length in the White Stork (Ciconia ciconia), a monomorphic species without visible sexual dimorphism, but characterized by differing parental efforts, which can be reflected by the small intestine lengths between the sexes. We examined the relationship between small intestine length and body size within the sexes. Our findings show that male White Storks have significantly shorter small intestines than females, despite having larger body sizes than the latter. Furthermore, we found a significant relationship between body size and small intestine length, but it was of a different nature in the two sexes. Males exhibited a previously unreported phenomenon, whereby increasing body size was associated with shortening small intestines, whereas females exhibited the opposite pattern. These novel findings shed light on the anatomical adaptations of the digestive tract in birds.
Syntactically aberrant vocalization in cuckoos disrupts communication but triggers host responses
Digit ratio in the common spadefoot toad Pelobates fuscus (Anura: Mesobatrachia: Pelobatidae): patterns and correlations
Urban Green Connectivity Assessment: A Comparative Study of Datasets in European Cities
Urban biodiversity and ecosystem services depend on the quality, quantity, and connectivity of urban green areas (UGAs), which are crucial for enhancing urban livability and resilience. However, assessing these connectivity metrics in urban landscapes often suffers from outdated land cover classifications and insufficient spatial resolution. Spectral data from Earth Observation, though promising, remains underutilized in analyzing UGAs’ connectivity. This study tests the impact of dataset choices on UGAs’ connectivity assessment, comparing land cover classification (Urban Atlas) and spectral data (Normalized Difference Vegetation Index, NDVI). Conducted in seven European cities, the analysis included 219 UGAs of varying sizes and connectivity levels, using three connectivity metrics (size, proximity index, and surrounding green area) at different spatial scales. The results showed substantial disparities in connectivity metrics, especially at finer scales and shorter distances. These differences are more pronounced in cities with contiguous UGAs, where Urban Atlas faces challenges related to typology issues and minimum mapping units. Overall, spectral data provides a more comprehensive and standardized evaluation of UGAs’ connectivity, reducing reliance on local typology classifications. Consequently, we advocate for integrating spectral data into UGAs’ connectivity analysis to advance urban biodiversity and ecosystem services research. This integration offers a comprehensive and standardized framework for guiding urban planning and management practices.
Disentangling the drivers of urban bird diversity in the non‐breeding season: A general synthesis
AbstractCurrent knowledge about the impacts of urbanisation on bird assemblages is based on evidence from studies partly or wholly undertaken in the breeding season. In comparison, the non‐breeding season remains little studied, despite the fact that winter conditions at higher latitudes are changing more rapidly than other seasons. During the non‐breeding season, cities may attract or retain bird species because they offer milder conditions or better feeding opportunities than surrounding habitats. However, the range of climatic, ecological and anthropogenic mechanisms shaping different facets of urban bird diversity in the non‐breeding season are poorly understood. We explored these mechanisms using structural equation modelling to assess how urbanisation affects the taxonomic, phylogenetic and functional diversity of avian assemblages sampled worldwide in the non‐breeding season. We found that minimum temperature, elevation, urban area and city age played a critical role in determining taxonomic diversity while a range of factors—including productivity, precipitation, elevation, distance to coasts and rivers, socio‐economic (as a proxy of human facilitation) and road density—each contributed to patterns of phylogenetic and functional diversity. The structure and function of urban bird assemblages appear to be predominantly shaped by temperature, productivity and city age, with effects of these factors differing across seasons. Our results underline the importance of considering multiple hypotheses, including seasonal effects, when evaluating the impacts of urbanisation on biodiversity.
COVID-19 facial covering during outdoor recreation reflects historical disease prevalence and culture above and beyond governmental measures – A study in 53 countries
Gender differences in birding specialization from 25 countries: effects are large in skill/knowledge and minimal in commitment
Abstract This study investigates gender differences in birding specialization, a leisure activity characterized by three dimensions: skill/knowledge, behavior, and psychological commitment. We used data from a worldwide survey during December 19th 2020 and April 16th 2021 from 25 countries and psychometrically validated instruments. A total of 4006 people (2737 men, 1269 women; mean age 50.13 years, SD = 16.5) participated in the study. Meta-analytical tools were used to analyze the results. Men reported higher levels of skill/knowledge (effect size d = 0.75), behavior ( d = 0.43), and psychological commitment ( d = 0.18) than women. Gender-related differences in skill/knowledge correlated with gender equality indices, indicating that differences between men and women are large in more gender-equal societies. Gender-related behavioral differences reflect societal constraints on women’s leisure due to care responsibilities, while men’s higher skills could be related to competitive tendencies in birding. The results align with the “gender-equality paradox,” suggesting greater gender differences in contexts of higher societal equality. Recommendations for future research include considering initiation age of the leisure activity, lifetime leisure/recreational experience, and societal factors influencing gender-specific participation in cognitive leisure activities.
Mobbing behaviour of hosts and non-hosts towards cuckoo Cuculus canorus of different sex
AbstractThe common cuckoo Cuculus canorus is an obligate brood parasite of many Eurasian bird species that exploit the parental care of their hosts. Although only females lay eggs in nests of passerine hosts, male and female cuckoos should cooperate to have a success in nest parasitism. Many bird species mobbing cuckoos as an element of deterrence of cuckoos from the breeding territory of the host. However, mobbing behaviour is costly, although only cuckoo females pose a threat to the dangers of the host. Because only the presence of a female cuckoo is dangerous, due to laying eggs in the nests of hosts, birds should mainly attack cuckoo females. Therefore, we tested for differences in anti-parasite response using field experiments with female and male cuckoo dummies, in 92 breeding sites with prime habitats in Poland. tested for differences in cuckoo responses in anti-parasite response using field experiments and cuckoo dummies (male and female) placed at 92 breeding sites with prime habitats in Poland. The host species that behaved most aggressively towards cuckoos was the barn swallow Hirundo rustica, while the most aggressive behaviour recorded in the non-host group was the great tit Parus major. Generally, host species reacted to cuckoo female dummies with a significantly higher probability than cuckoo males dummies. We conclude that differences in reaction by hosts and non-hosts may have arisen from selection for recognition of danger (parasite female) by reduction of reproductive success.
Day-after impact of simulated rival encounter in the common cuckoo
AbstractStudies show that the common cuckoo exhibits a strong vocal response to rival playback. In this study, we aimed to assess if males would more eagerly vocally defend their home ranges a day after a simulated rival encounter. At 48 sites in Poland, we conducted a playback experiment where we played 20 calls repeated 5 times with a 5-min break between each series. Using the automatic analysis software Kaleidoscope Pro, we detected cuckoo calls in two datasets, directly after the experiment and the day after. Our results show that even though cuckoos respond to rival calls, this response is short-lived.
