acta ethologica最新文献

Understanding consistent inter-individual variability in animal behaviour, known as personality traits, is essential for exploring the mechanisms and evolutionary consequences of behavioural diversity. Aggressive behaviour influences survival, resource acquisition, and reproduction, so clarifying individual differences can enhance our understanding of ecological dynamics and improve experimental design accuracy in behavioural studies. In this study, ornamental male Betta splendens, a model organism for aggression research, were analysed for intra- and inter-individual variability in aggressive responses to their mirror image—a standard method for assessing aggression in fish—once per week, and their consistency was evaluated over three consecutive weeks There were significant differences in aggressive behaviour across individuals, with coefficients of variation ranging from 29 to 60%. While most fish exhibited the full suite of aggressive displays, some showed no aggressive behaviour, while others only displayed threat behaviours but did not advance to the attacks. The consistency of individual threat and attack behaviours varied, but repeatability was high overall (intra-class correlation coefficients ≥ 0.5), indicating that individual fish have different levels of aggression. There was habituation to the mirror assay, with aggression decreasing significantly by the second week, though the degree of habituation, a form of learning, varied among individuals in some behaviours. Air-breathing frequency correlated positively with aggression behaviours and can be considered an indicator to infer aggression level in this species. These results indicate that inter-individual variation in aggressive behaviour and habituation to repeated testing using the mirror assay should be considered in aggression studies using B. splendens and potentially in other species.

The larvae of parasitoid wasps of the Polysphincta genus group (Ichneumonidae: Pimplinae), in addition to exploiting their host spiders as a food resource, often also change the web-building behavior of spiders to favor their chances of survival in the pupal stage. In this study, we find that the spider Anelosimus jucundus (Araneae: Theridiidae) is a host of the wasp Zatypota baezae Pádua & Sobczak, 2019 (Hymenoptera: Ichneumonidae), and describe the cocoon webs built by this spider species under the influence of wasp larvae. The cocoon web induced in A. jucundus by Z. baezae consists of an outer web that is closed on almost all sides. Only some areas of the upper, lateral or lower region of the outer web present some openings that lead to the inner region of the web where the wasp's cocoon is built vertically. The construction of the cocoon web occurs gradually, two days before the death of the spider. These behavioral changes induced in A. jucundus are similar to those observed in other species of spiders of the genus Anelosimus induced by other wasps of the genus Zatypota.

Recent years have witnessed the emergence of extensive new data suggesting a different view of inheritance from the view that has dominated biology for over a century. It suggests that what is transmitted across generations are the developmental means to construct phenotypes predicted to match anticipated environmental conditions. Those ‘developmental means’ include genes, but also other resources that parents bequeath to descendants, as well as activities parents engage in to construct the environmental context in which their offspring develop. If there are similarities between the traits of parents and offspring it is because, within lineages, phenotypes are reliably re-constructed across generations. Extra-genetic inheritance processes do an important job in evolution, but that job is, in the main, distinct from that of genetic inheritance. They are best regarded – not as noise, fine-tuning or baroque “add ons” (Wray et al. 2014) – but as essential tools for short-term, rapid-response adaptation. The true function of heredity is to make an informed forecast.

In ethological studies of birds, the zebra finch (Taeniopygia guttata) has played a major role as an excellent lab model species in recent decades, while other non-model species that belong to the same taxonomic group (family Estrildidae, estrildid finches) have also been characterized with intriguing ecological or morphological features worthy of attention from comparative perspectives. Therefore, this short review paper aims to bring together past findings on non-model estrildid finch species. It focuses on sexual or social signaling traits, which include plumage pattern and coloration, colored bare parts, and courtship displays (dance and song), to be compared with zebra finch findings and provide future directions for research. Overall, estrildid finches tend to have multiple ornamentations and mating signals that can be shared between the sexes, suggesting that research insights from this group would contribute to our understanding of mutual (or male) mate choice, and evolution of multiple signaling traits that include song (or female song).

Amphibians have evolved diverse anti-predator defences, including behavioural ones. One of the best known is unkenreflex. It was described for the first time in Firebellied Toads Bombina; spp. and it is, in its classic form, a display of conspicuous underside by lifting limbs and arching back upon disturbance. Unkenreflex has also been recorded in other anurans, but its prevalence across species has not been extensively studied so far. Here, we present our own observations and review published records, distinguishing full and partial unkenreflex. We document 23 cases of unkenreflex, including the first records in Pelobates fuscus, Bufotes viridis, Bufo bufo, Pelophylax esculentus complex, and Hyla arborea. Combining these findings with previously published records, in 43 species partial unkenreflex has been reported, in 34 species full unkenreflex, while both types were observed in seven species. Regarding family and biogeographic realm, the True Toads (Bufonidae) and Neotropics had the highest number of species in which unkenreflex was reported. Our review clearly shows that unkenreflex is more widespread among anurans than previously thought. Full unkenreflex likely conveys survival advantages through aposematism and deimatism, while partial reflex may rely on mechanisms such as protecting eyes, increasing body width to deter swallowing, obscuring head location, and feigning death (thanatosis). Robust large-scale sampling and experiments are needed to fully elucidate the prevalence, role, distal mechanisms, and evolution of this fascinating and understudied behaviour.

The earliest response to natural and anthropogenic changes in the environment is typically behavioural. Due to the relevance of animal behaviour in predicting and mitigating the impacts of environmental changes on populations and ecosystems the interdisciplinary field of Conservation Behaviour has recently emerged. While it was formally acknowledged as a discipline about 30 years ago, it was only in 2011 that a theoretical framework was proposed by Berger-Tal and colleagues. Currently, numerous examples illustrate the use of animal behaviour in conservation and management efforts. However, most of these examples involve terrestrial animals. This is partly because both the behaviour and habitats of terrestrial animals are more accessible than those in the marine environment. Here, I provide an overview on how animal behaviour can contribute to marine conservation, namely in assessing anthropogenic impacts on animal behaviour, using behaviour as indicators and in guiding conservation and management interventions, using examples from the marine environment. Finally, I discuss future directions and how major technological advances in equipment and in artificial intelligence can be critical for developing effective conservation strategies and policies in a rapidly changing world.

The tribe Anthidiini, from the family Megachilidae, includes cleptoparasitic and solitary species that nest in pre-existing cavities. In solitary species, females perform all nesting and oviposition activities without contact with their offspring. Although the life cycle of some solitary bees is known, the processes preceding the emergence of these individuals are still poorly understood. This study focused on the pre-emergent behavior of Ephanthidium tigrinum and Dicranthidium arenarium, using transparent trap nests for daily observation. Both active (movement; cell wall excavation; agonistic interaction; excavation of the closing plug and cleaning) and inactive (rest and sleep) behaviors were recorded. In both species, the emergence process began in the morning, days before the first bee emerged, suggesting a collective preparation. The study provides valuable insights into this behavior.

The social behaviour of rodents has captivated scientists for decades, offering valuable insights into the evolution of mammalian sociality. One of the main critical gaps in understanding rodent sociality is the role of subadult individuals prolonging their stay with parents and younger siblings, particularly in nocturnal and elusive species. Moreover, urban environments are known to elicit changes in the social behaviour of mammals, leading to altered patterns of sociality. Yet, little is known on how rodent societies may change in altered environments. Thus, we aimed at investigating the social behaviour of the crested porcupine Hystrix cristata in central Italy, with a particular focus on group composition and on the prolonged occurrence of subadult individuals within family groups. We also tested the potential effects of natural and urban environments. We combined marking of free-ranging individuals with camera trapping campaigns across three ecologically contrasting areas, and showed a pair-living social system for adult crested porcupines. Most videos captured either single young individuals or pairs of adults. Subadult marked females were observed together with adults during the birth season in the year following their birth, suggesting a potential helping role. Conversely, subadult marked males were rarely observed, presumably dispersing. Groups exceeding two individuals ranged between three and five, and were typically observed following reproductive events, with porcupines commuting in line, parents positioned at head and tail of the row. Urban environments showed a slightly different pattern, with occasional aggregations of subadults. We highlight the importance of understanding subadult behaviour in crested porcupines, as well as of testing the effects of urban ecosystems upon mammalian social systems. These findings contribute to a broader understanding of social behaviour and evolutionary adaptations in rodents and, more in general, of mammals.

The emerging field of macrobehaviour explores behavioural variation across large geographic, taxonomic, and temporal scales, and its ecological and evolutionary consequences. This unifying framework merges macroecology with ethology, both enhancing our understanding of how behaviour mediates ecological dynamics at scales above the population level, and offering an approach that can broaden the impact of ethological research. Here, I urge ethologists to engage with the field, outlining what “macro” means, why we must act now, why we need your expertise, how you can get involved, and how this line of research offers reciprocal benefits to both disciplines. Together, we can amplify the impact of ethological research while accelerating insight that could inform solutions to the global biodiversity crisis.