The Science of Nature最新文献

We investigated acoustic variation responsible for the individuality of alarm calls produced by 50 Brandt’s voles Lasiopodomys brandtii derived from 50 different wild-living colonies. For the first time, we described the calling pattern of Brandt’s voles, producing a long series of short alarm calls with short inter-call intervals. The alarm calls displayed four different contours of fundamental frequency but were nevertheless strongly individually distinct within a series of 50 successive alarm calls per caller (2500 analyzed alarm calls). The average value of correct assignment of alarm calls to individuals with discriminant function analysis was 15 times higher than the value expected by chance and was robust, not decreasing with cross-validation. We discuss that the highly individualistic alarm calls provide a basis for individual recognition of callers by colony members. At the same time, heterogeneity of call contours makes the long call series less monotonous, potentially preventing habituation and promoting alertness of conspecific call recipients.

Longhorn beetles (family Cerambycidae) are globally distributed insects with important ecological roles. Here we present the first discovery of fossil longhorn beetles from Australia. The two new taxa described, Ventiala beattiei gen. et sp. nov. and Ferrucornus gulgongensis gen. et sp. nov. are from McGraths Flat, New South Wales, a finely-layered (laminated) fossiliferous goethite deposit dated to the Miocene (11–16 million years ago). One specimen hosts a nematode, providing rare insight into ancient species interactions. These findings enhance our understanding of Miocene mesic ecosystems and underscore the importance of McGraths Flat as a crucial site for studying the evolutionary history of Australia's terrestrial arthropod biodiversity.

Fear of snakes is common not only in humans but also in other primates. Consequently, snakes are salient stimuli associated with prioritized attention, early detection and emotional significance. This has been interpreted as an adaptive evolutionary response of the primate brain to a risk of envenoming by a hidden snake. However, the struggle between mammals and snakes is not one-sided. Humans and carnivores regularly kill snakes, and thus snakes develop deterring defensive behaviour that may directly evoke enhanced fear. Here, we show that snakes depicted in threatening posture evoked on average more fear than those in resting posture. Significantly, African (Somali) and European (Czech) respondents considerably agreed on the relative fear elicited by various snakes. Nonetheless, not all defensive postures are equally efficient. Threatening cobras were perceived as top fear-evoking stimuli, even though most of them are not considered very frightening in resting posture. This effect can be attributed to their conspicuous hooding posture which evolved into an efficient warning signal for mammalian predators. Our result demonstrates that cobras are more effective than other snakes in the ability to evoke human fear by a simple behavioural display—hooding. This can be primarily explained by the behavioural evolution of cobras which successfully exploited pre-existing cognitive mechanisms of mammals. Whether human ancestors cohabiting with deadly venomous cobras further improved their fear response to hooding is uncertain, but likely.

To understand the distribution of Atlas pistachio (Pistacia atlantica Desf.) in Algeria, we analyzed the environmental factors influencing its habitat. This study employs an ensemble modelling (EM) approach, a robust predictive technique in ecological niche modelling that enables us to identify critical environmental drivers affecting plant distributions across different ecosystems’ focal species. The EM incorporated four prediction algorithms (generalized linear model, boosted regression trees, random forest, and maximum entropy algorithms); we modelled Atlas pistachio’s niche with 2810 occurrence points and 32 environmental variables, including climatic, edaphic, topographic, and anthropogenic factors. The model demonstrated high accuracy, with an AUC of 0.97 and TSS of 0.88. Key factors influencing distribution were precipitation in the driest month (Bio14), soil bulk density (BD), cation exchange capacity (CEC), human modification, and average diurnal amplitude (Bio2), with a relative importance of 20.1%, 12.7%, 6.7%, 4.9%, and 3.1%, respectively. These findings underscore the utility of ensemble modelling to pinpoint specific environmental variables critical to the species’ presence and ecological adaptability, which has broader implications for other plant species in arid landscapes. Notably, the probability of Atlas pistachio occurrence increased with BD and decreased with CEC and human influence. Our results emphasize the EM approach as a versatile tool in ecological modelling, facilitating species-specific analyses that contribute to broader ecological restoration efforts, especially in degraded arid and semi-arid regions. This study advances our understanding of Atlas pistachio’s environmental requirements and highlights the importance of EM in developing targeted programs to restore degraded ecosystems.

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Acroceridae are active parasitoids of mygalomorph spiders. However, little is known of their interaction numbers and biology in the Neotropics. In this study, we present 15 new records of acrocerid–mygalomorph interactions, adding new biological information about spider fly development. Mygalomorph spiders were captured in the field and maintained in captivity, and the development time of acrocerids was followed from the 4th instar to adulthood. Only seven acrocerid flies were able to complete their development. The acrocerids obtained were Arrhynchus stuardoi, Arrhynchus maculatus, and Archipialea sp. The total recorded development time (from the point where the larva leaves its host to the eclosion of the adult fly) of the spider flies was between 20 and 29 days. The collaboration of citizen scientists could be a useful alternative in the future to fill gaps in the biological and ecological information about these parasitoid flies.

The global postdoctoral community faces many challenges including low pay, irregular benefits, little job security amid cost-of-living hikes, challenges to mental health, and power imbalances. Conclusions from the 2020 and 2023 global postdoctoral surveys by Nature highlighting these struggles are highly skewed towards respondents from the Global North, underrepresenting the Global South. Here, we address the postdoctoral struggles of scholars in the Global South who are more vulnerable due to low-income economy and patriarchal society that discriminates against women. We argue that neglecting postdoctoral researchers in basic science fields, women and scholars from local and regional universities will affect global academic and research outputs. We recommend sustainable, long-term solutions such as “Postdoc Representative Body” ensuring just and wider postdoctoral benefits at country level to secure postdoctoral benefits in the Global South.

Knotweed (Reynoutria sp.) plants are known in the world mainly as invasive plants. However, it is known that their rhizomes or leaves contain secondary metabolites with biological activity. Our goal was to determine which of the three knotweed plants (Reynoutria japonica, Reynoutria × bohemica, and Reynoutria sachalinensis) is most suitable for seed growth stimulation. We tested alcoholic extracts of all three knotweed species by seed priming method on wheat germination and seedling characteristics, when 12 measured characteristics were monitored. Extracts from all three species of Reynoutria sp. generally showed an improvement in wheat germination and growth compared to the control. R. × bohemica appears to be the best source for stimulating wheat growth, as seedling vigor indexes I and II, R/S dry weight, shoot and seedling lengths, root, shoot, and seedling dry weights were significantly different (ANOVA, Duncan’s test, α < 0.05). The plants Reynoutria spp. seem to be possible sources for the protection and stimulation of agriculture crops.

Habitat selection by spiders is strongly influenced by biotic factors such as the availability and diversity of prey and abiotic factors such as temperature, humidity, and the structural complexity of the habitat. Structural complexity is an aspect that intensely affects species persistence, population stability, and the coexistence of interacting species. Trees comprise a complex set of microhabitats due to their large biomass and heterogeneity of the architectural components of their trunk surface and branches. Spider species that live on trunks have diversified physiological or morphological adaptations that confer advantages in this environment. In this study, we experimentally examined the habitat choice by the tree-dwelling spiders Selenops cocheleti (Selenopidae), Corinna rubripes (Corinnidae), and Loxosceles gaucho (Sicariidae). We found that microhabitat specialization was restricted to trunk architectural characteristics rather than plant taxonomy. Selenops cocheleti and C. rubripes significantly preferred loose barks and holes in the trunks, respectively, showing that both spider species can evaluate the physical structure of the microhabitat on a fine scale. On the other hand, L. gaucho selected crevices and holes near the base of the trunk without giving much importance to the physical characteristics of the microhabitat per se (e.g., depth, height, length). Our findings indicate that for generalist predators like spiders, coexistence relies heavily on spatial segregation driven by distinct habitat preferences, irrespective of their method for capturing prey.

Wildlife forensics plays a pivotal role in the combating illegal trafficking, supporting biodiversity conservation, and aiding in the identification of animals in wildlife. Animal hair, often found in trafficking crimes, serves as vital biological evidence that can provide significant information for animal identification. This study proposes a novel method integrating machine learning classifiers with Fourier transform infrared (FTIR) spectroscopy in attenuated total reflectance (ATR) mode to enhance the effectiveness of animal identification in wildlife forensic casework. Additionally, compound microscopy has also been utilized as a preliminary tool to perform morphological analysis of hair samples from four animal families, including Bovidae, Cervidae, Elephantidae, and Felidae. Further, chemical profiling through spectral data revealed significant overlapping peaks between family Bovidae and Cervidae. The classification experiment provides the random forest (RF) classifier as the most effective for family discrimination model. This research offers valuable insights for wildlife forensics by improving the identification accuracy of unknown hair samples, thus enhancing the overall effectiveness in forensic investigations.

Graphical Abstract

Investigating the conspicuousness of animal color patterns to different observers is crucial for understanding their function. This study examines the peculiar case of a jumping spider (Saitis barbipes) whose males display red and black ornaments during courtship despite an apparent inability to distinguish these colors. We propose that, through predator eyes, red may actually be a better match than black to the spiders’ leaf litter background, and that the black fringe of hairs surrounding red ornaments may blur with red at natural predator acuities and viewing distances to produce a background-matching desaturated red. In a field experiment, we test whether red ornaments reduce predation relative to red ornaments painted black, and find that, unexpectedly, spiders with red ornaments are more heavily predated upon. Having established birds as the spiders’ primary predators, we image the spiders in their natural habitat using an avian-vision camera. We find their red coloration to have similar color contrast, but lower achromatic contrast, with the background than black coloration. We also find that red and black elements blur together at typical avian acuities and viewing distances to produce lower chromatic and achromatic contrasts with the background than would be seen by animals with higher acuities and/or closer viewing distances. Interestingly, red ornaments appear orange or yellow when viewed obliquely, which reduces their achromatic, but not chromatic, contrast with the background. Our imaging results provide support for our hypothesis that red is camouflaging, whereas the results of our predation experiment do not. Any functional significance of the spiders’ red coloration therefore remains unresolved.