Do bats' social vocalizations conform to Zipf's law and the Menzerath-Altmann law?

The study of vocal communication in non-human animals can uncover the roots of human languages. Recent studies of language have focused on two linguistic laws: Zipf's law and the Menzerath-Altmann law. However, whether bats' social vocalizations follow these linguistic laws, especially Menzerath's law, has largely been unexplored. Here, we used Asian particolored bats, Vespertilio sinensis, to examine whether aggressive vocalizations conform to Zipf's and Menzerath's laws. Aggressive vocalizations of V. sinensis adhere to Zipf's law, with the most frequent syllables being the shortest in duration. There was a negative association between the syllable number within a call and the average syllable duration, in agreement with Menzerath's law. A decrease in the proportion of some long syllables and a decrease in the duration of several syllable types in long-duration calls explain the occurrence of this law. Our results indicate that a general compression principle organizes aspects of bat vocal communication systems.

What is it like to be a bot? The world according to GPT-4.

The recent explosion of Large Language Models (LLMs) has provoked lively debate about "emergent" properties of the models, including intelligence, insight, creativity, and meaning. These debates are rocky for two main reasons: The emergent properties sought are not well-defined; and the grounds for their dismissal often rest on a fallacious appeal to extraneous factors, like the LLM training regime, or fallacious assumptions about processes within the model. The latter issue is a particular roadblock for LLMs because their internal processes are largely unknown - they are colossal black boxes. In this paper, I try to cut through these problems by, first, identifying one salient feature shared by systems we regard as intelligent/conscious/sentient/etc., namely, their responsiveness to environmental conditions that may not be near in space and time. They engage with subjective worlds ("s-worlds") which may or may not conform to the actual environment. Observers can infer s-worlds from behavior alone, enabling hypotheses about perception and cognition that do not require evidence from the internal operations of the systems in question. The reconstruction of s-worlds offers a framework for comparing cognition across species, affording new leverage on the possible sentience of LLMs. Here, we examine one prominent LLM, OpenAI's GPT-4. Inquiry into the emergence of a complex subjective world is facilitated with philosophical phenomenology and cognitive ethology, examining the pattern of errors made by GPT-4 and proposing their origin in the absence of an analogue of the human subjective awareness of time. This deficit suggests that GPT-4 ultimately lacks a capacity to construct a stable perceptual world; the temporal vacuum undermines any capacity for GPT-4 to construct a consistent, continuously updated, model of its environment. Accordingly, none of GPT-4's statements are epistemically secure. Because the anthropomorphic illusion is so strong, I conclude by suggesting that GPT-4 works with its users to construct improvised works of fiction.

Mapping the Behavioral Signatures of Shank3b Mice in Both Sexes.

Autism spectrum disorders (ASD) are characterized by social and repetitive abnormalities. Although the ASD mouse model with Shank3b mutations is widely used in ASD research, the behavioral phenotype of this model has not been fully elucidated. Here, a 3D-motion capture system and linear discriminant analysis were used to comprehensively record and analyze the behavioral patterns of male and female Shank3b mutant mice. It was found that both sexes replicated the core and accompanied symptoms of ASD, with significant sex differences. Further, Shank3b heterozygous knockout mice exhibited distinct autistic behaviors, that were significantly different from those those observed in the wild type and homozygous knockout groups. Our findings provide evidence for the inclusion of both sexes and experimental approaches to efficiently characterize heterozygous transgenic models, which are more clinically relevant in autistic studies.

Effect of transportation distance and lairage time on selected behaviors and carcass parameters in zebu cattle-a study using the animal focal sampling method.

The objective of this study was to evaluate the effect of the transport distance and lairage time on behavioral indicators of zebu beef cattle in the resting pen of a slaughterhouse using the focal animal technique. Eight lots of male zebu cattle, Nelore, aged approximately 4 years old, weighing on average 500 ± 28.5 kg-1, from different municipalities, transported by land, were evaluated. The lots were grouped into two categories: short distance (> 500 km) and long distance (> 500 km). Five focal animals per evaluated lot were used in each cycle of behavior observation, randomly chosen, and visually identified. The animal focal sampling method was used, with instantaneous recording, every 5 min per animal/h. A video camera was used and placed at a fixed point in the corral. After slaughtering, bruises and carcass pH were evaluated. The respiratory rate (RR) was measured in two moments, 30 min after unloading (RR_I) and 1 h before slaughtering (RR_F); behavioral data were divided into four lairage periods (1st, 2nd, 3rd, and 4th) equally and evaluated as repeated measures over time. The lairage time lowered the behaviors of headbutting (NCHBs), pushing (PsH), mounting (MT), and chasing away (CA), (p = 0.0001), and these behaviors were more evident in animals transported for short distances in the initial resting times, decreasing as they remained in the resting pen. There was effect of distance on the initial and final pH of the carcass, being greater in the short distance (p = 0.047). There was no effect of distance or lairage time on initial or final RR (p > 0.05). In addition, animals transported over long distances showed less carcass injuries, which were observed during post mortem inspection. It is concluded that animals transported over short distances present a greater number of agonistic behaviors, such as NCHBs, MT, PsH, and CA, predisposing to higher rates of bruising during lairage and more accentuated changes in the final pH of the meat.

Behavioral indicators of heterogeneous subjective experience in animals across the phylogenetic spectrum: Implications for comparative animal phenomenology.

This behavioral study was undertaken to provide empirical evidence in favor of or opposed to the notion that animals across a wide breadth of the animal kingdom have subjective (personal) experience that varies with their lifestyles, ecological constraints, or phylogeny. Twelve species representing two invertebrate phyla and six vertebrate classes were observed unobtrusively in 15-min episodes, during which three modes of behavior (volitional, interactive, and egocentric) were quantified according to the frequency, variety, and dynamism of each mode. Volitional behavior was the most prevalent and dynamic mode for nearly all species, largely without regard to phylogenetic position. Interactive behavior likewise varied inconsistently across the entire evolutionary spectrum. Egocentric behavior was concentrated among the avian and mammalian species, but evidence of it were observed in the invertebrate species as well. Diagrams of the matrix constructed from the three qualitative modes and three quantitative attributes for each mode provide a metaphorical representation of the unique experiential profile of each species. To the extent that these behavioral measures correlate with the nature of the animal's subjective experience, they support the growing view that phenomenology is heterogeneous, multimodal, and non-linear in extent across the animal kingdom.

The behavioural costs of overcrowding for gregarious cave-dwelling bats.

Bats are known for their gregarious social behaviour, often congregating in caves and underground habitats, where they play a pivotal role in providing various ecosystem services. Studying bat behaviour remains an underexplored aspect of bat ecology and conservation despite its ecological importance. We explored the costs and impacts of overcrowding on bat social behaviour. This study examined variations in bat behavioural patterns between two distinct groups, aggregated and non-aggregated male Rousettus amplexicaudatus, within the Monfort Bat Cave Sanctuary on Mindanao Island, Philippines. We found significant variations in the incident frequencies of various bat behavioural activities, particularly aggression and movement, between these two groups. The increase in aggregation was closely related to negative social behaviour among bats. In contrast, sexual behaviour was significantly related to the positive behaviour of individual bats and was headed in less crowded areas. The disparities in bat behaviour with an apparent decline in bat social behaviour because of overcrowding, with more aggressive behaviours emerging, align with the 'behavioural sink' hypothesis. Our study underscores the importance of considering habitat quality and resource availability in the management and conservation of bat colonies, as these factors can reduce the occurrence of aggressive and negative social behaviours in colonies with high population density by providing alternative habitats.

Chemical symphony: Unraveling triatomine aggregation and attraction patterns for innovative pest control solutions.

Aggregation is a spatial distribution pattern where individuals can be grouped through interaction with particular signals or cues [e.g., chemical substances]. Numerous triatomine species exhibit attraction and aggregation around both conspecific and heterospecific feces. It remains unclear whether compounds released by feces function as signals (pheromones or synomones) or cues. Employing a bioassay that mimics field conditions, we investigated the response of Triatoma pallidipennis bugs to volatiles present in its feces and blends of these compounds. Our findings indicate that short-chain aldehydes, namely nonanal, octanal, heptanal, and hexanal, attract fifth-instar nymphs. Furthermore, insects responded to individual compounds as well as secondary, ternary, and quaternary blends. The most attractive blend consisted of all four aldehydes. Additionally, quaternary blends at various compound ratios attracted fifth-instar nymphs of T. phyllosoma and T. longipennis. We discuss the potential roles of these compounds as signals or cues and explore their application as bait in control programs.

Post-urethroplasty complications in hypospadias repair: a systematic review and meta-analysis comparing polydioxanone and polyglactin sutures.

Background: Polyglactin (PG) and polydioxanone (PDS) sutures are extensively used based on the surgeon's preference. The development of post-reconstruction urethrocutaneous fistula (UCF) is variably attributed to the choice of suture material for urethroplasty. This meta-analysis compares complications of hypospadias repair using PG and PDS sutures. Methods: The systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The authors conducted thorough searches in databases including MEDLINE, EMBASE, CENTRAL, Scopus, Google Scholar, and clinical trial registries. Outcome measures included UCF, meatal stenosis, wound infection, urethral stricture, glans dehiscence, and overall complications. Quantitative analysis was used with fixed or random-effect models to find the pooled risk ratio and I2 heterogeneity. Results: The criteria for inclusion were met by five comparative studies with the inclusion of 1244 children altogether. Pooled analysis failed to show a statistically significant difference in the incidence of meatal stenosis, urethral stricture, wound infection, and total complications using PG and PDS sutures. However, it showed a reduction in the incidence of UCF with PDS suture hypospadias repairs (risk ratio=0.66, 95% CI 0.48 to 0.92). Conclusions: PDS sutures are associated with decreased incidence of UCF than PG after hypospadias repair. The incidence of meatal stenosis, urethral stricture, wound infection, and total complications was not affected by the type of suture material used for repair. Clinical implications: This meta-analysis suggests decreased incidence of UCF when PDS sutures are used for hypospadias repair which may impact the choice of suture material for repair. PROSPERO registration number: CRD42023409710.

Automatic identification of stone-handling behaviour in Japanese macaques using LabGym artificial intelligence.

The latest advances in artificial intelligence technology have opened doors to the video analysis of complex behaviours. In light of this, ethologists are actively exploring the potential of these innovations to streamline the time-intensive behavioural analysis process using video data. Several tools have been developed for this purpose in primatology in the past decade. Nonetheless, each tool grapples with technical constraints. To address these limitations, we have established a comprehensive protocol designed to harness the capabilities of a cutting-edge artificial intelligence-assisted software, LabGym. The primary objective of this study was to evaluate the suitability of LabGym for the analysis of primate behaviour, focusing on Japanese macaques as our model subjects. First, we developed a model that accurately detects Japanese macaques, allowing us to analyse their actions using LabGym. Our behavioural analysis model succeeded in recognising stone-handling-like behaviours on video. However, the absence of quantitative data within the specified time frame limits the ability of our study to draw definitive conclusions regarding the quality of the behavioural analysis. Nevertheless, to the best of our knowledge, this study represents the first instance of applying the LabGym tool specifically for the analysis of primate behaviours, with our model focusing on the automated recognition and categorisation of specific behaviours in Japanese macaques. It lays the groundwork for future research in this promising field to complexify our model using the latest version of LabGym and associated tools, such as multi-class detection and interactive behaviour analysis.

Seasonal variations in botanical and nutritive composition, forage availability and ingestive behavior of grazing goats in the semiarid region.

The aim of this study was to assess how the different seasons of the year impact the botanical composition, availability, and quality of forage in the caatinga, as well as the frequency of ingestion and ingestive behavior of goats in a semi-arid region. The experiment used four crossbred castrated males, with an average weight of 30.2 ± 4.76 kg and an average age of 20 months. The experimental period lasted for 12 months, encompassing two rainy seasons and one dry season within this timeframe, with three replications (data collection) per season. All collected forage was categorized based on its stratum (herbaceous, woody, and litter), and a chemical composition analysis was conducted. The goats' behavior was assessed by observing variables such as feeding time, idleness, rumination, displacement, social interaction, and water intake. The findings revealed clear seasonality in both availability and quality of forage, consequently influencing the botanical composition of the goats' diet and their ingestive behavior. In addition, during the grazing period, the goats showed a shift grazing habit, in which idle and feeding peaks were alternated with increased displacement during the morning and rumination in the afternoon. The seasons of the year strongly impact the availability and nutritional quality of forage in the caatinga biome, consequently influencing the ingestive behavior and dietary composition of goats in this ecosystem.

Effects of forest fragmentation on the dietary ecology and activity of a nocturnal lemur community in North West Madagascar.

Deforestation and habitat fragmentation is the primary threat to primate populations. The primates that live within degraded and anthropogenically disturbed habitats typical of fragmented landscapes have to cope with lower availability of resources in comparison to primates in continuous, undisturbed forests. While some species are sensitive to forest fragmentation, some evidence exists to suggest that primates can alter their behavior and adapt to such changes, which enables their survival in suboptimal habitat. In this study, we assessed how forest fragmentation and its associated edge-effects impact the feeding ecology and activity levels of a nocturnal primate community in the Sahamalaza-Iles Radama National Park, North West Madagascar. From March 06, 2019 to May 17, 2022, we collected data on tree and invertebrate phenology at our study site, and feeding ecology and activity for 159 lemur individuals from four species. Fruit and flower availability varied significantly between continuous and fragmented forest, and between forest core and edge areas, with continuous forest exhibiting higher continuous fruit and flower availability. Lemur feeding ecology varied significantly too, as the feeding niches of all four species were significantly different between continuous and fragmented forest and between core and edge areas. However, lemur activity levels were mostly consistent among all forest areas. The results of this study suggest that nocturnal lemurs are able to adapt their dietary ecology in response to the available food sources within their habitat. Due to this flexible ecology and dietary plasticity, the lemurs do not need to significantly alter their behavior in different environments to fulfill their dietary needs. While nocturnal lemurs demonstrate adaptability and flexibility to degraded habitat, it is unclear how far this plasticity will stretch considering that Madagascar's forests are still being cleared at an alarming rate. Urgent conservation action is therefore needed to ensure the future of lemur habitat.

Atractylenolide I improves behaviors in mice with depression-like phenotype by modulating neurotransmitter balance via 5-HT2A.

To explore the antidepressant effects and targets of atractylenolide I (ATR) through a network pharmacological approach. Relevant targets of ATR and depression analyzed by network pharmacology were scored (identifying 5-HT2A targets). Through elevated plus maze, open field, tail suspension, and forced swimming tests, the behavioral changes of mice with depression (chronic unpredictable mild stress [CUMS]) were examined, and the levels of neurotransmitters including serotonin, dopamine, and norepinephrine (5-HT, DA, and NE) were determined. The binding of ATR to 5-HT2A was verified by small molecular-protein docking. ATR improved the behaviors of CUMS mice, elevated their levels of neurotransmitters 5-HT, DA, and NE, and exerted a protective effect on their nerve cell injury. After 5-HT2A knockout, ATR failed to further improve the CUMS behaviors. According to the results of small molecular-protein docking and network pharmacological analysis, ATR acted as an inhibitor by binding to 5-HT2A. ATR can improve the behaviors and modulate the neurotransmitters of CUMS mice by targeting 5-HT2A.

Habituação ou sensibilização? Efeito comportamental em Cascavel sul-americanas (Crotalus durissus)

The defensive behavior represents a crucial strategy for snakes, influenced by intrinsic factors that play significant roles in the survival, reproduction, and evolution of species. The present study focused on the rattlesnake (Crotalus durissus), a species exhibiting a wide variety of defensive behaviors. The research aimed to assess the manifestation of habituation or sensitization in the defensive behavior of rattlesnakes, establishing a comparison between adult and young individuals. For this purpose, 44 snakes (22 juveniles and 22 adults) kept in captivity were subjected to encounters with a white-eared opossum plush model in a controlled arena. Data collection extended over a period of 6 days, during which behaviors were recorded. The statistical analysis employed a mixed-effects generalized linear model (GLMM) with Poisson distribution, using R software (version 3.34). The results revealed an increase in aggression in both adult and juvenile groups on the sixth day. Notably, juveniles exhibited higher responsiveness and aggression compared to adults. This study provided clear evidence of ontogenetic differences in the selection of defensive strategies between juveniles and adults. This distinction was influenced by experience, limitations, and inherent needs at each life stage of the snakes. Contrary to expectations based on the literature, both juvenile and adult groups did not exhibit habituation to the presented stimuli, indicating instead a sensitization phenomenon. These findings emphasize the importance of considering ontogenetic variables when analyzing defensive behavior in snakes, particularly in the context of predator-prey interactions. Furthermore, the results have practical implications, especially in regions where the presence of rattlesnakes may pose risks to the community. This study contributes to a deeper understanding of defensive behavior patterns in rattlesnakes, providing valuable insights for management and conservation strategies in controlled environments.

O comportamento defensivo representa uma estratégia crucial para as serpentes, sendo influenciado por fatores intrínsecos que desempenham papéis significativos na sobrevivência, reprodução e evolução das espécies. O presente estudo concentrou-se na cascavel (Crotalus durissus), uma espécie que exibe uma ampla variedade de comportamentos defensivos. O objetivo da pesquisa consistiu em avaliar a manifestação de habituação ou sensibilização do comportamento defensivo em cascavéis, estabelecendo uma comparação entre indivíduos adultos e jovens. Para tanto, foram empregadas 44 serpentes (22 filhotes e 22 adultos) mantidas em cativeiro, submetidas a confrontos com um modelo de pelúcia de gambá-de-orelha-branca em uma arena controlada. A coleta de dados estendeu-se por um período de 6 dias, durante os quais foram registrados os comportamentos. A análise estatística adotada foi conduzida por meio de um modelo linear generalizado misto (GLMM) com distribuição de Poisson, utilizando o Software R (versão 3.34). Os resultados revelaram um aumento na agressividade tanto nos grupos de adultos quanto de filhotes no sexto dia. Destacou-se que os filhotes apresentaram maior responsividade e agressividade em comparação com os adultos. Este estudo proporcionou evidências claras de uma diferença ontogenética na escolha de estratégias defensivas entre filhotes e adultos. Tal distinção foi influenciada pela experiência, limitações e necessidades inerentes a cada fase de vida das serpentes. Contrariando as expectativas baseadas na literatura, ambos os grupos, filhotes e adultos, não manifestaram habituação aos estímulos apresentados, indicando, em vez disso, um fenômeno de sensibilização. Esses achados enfatizam a relevância de considerar as variáveis ontogenéticas ao analisar o comportamento defensivo em serpentes, particularmente no contexto das interações presa-predador. Além disso, os resultados possuem implicações práticas, especialmente em regiões onde a presença de cascavéis pode representar riscos para a comunidade. Este estudo contribui para uma compreensão mais aprofundada dos padrões de comportamento defensivo em cascavéis, fornecendo insights valiosos para estratégias de manejo e conservação em ambientes controlados.

O estudo do comportamento, a dicotomia inato vs. aprendido e sua (possível) superação / Behavior studies, the nature vs. nurture dichotomy and its (possible) overcoming / El estudio del comportamiento, la dicotomía innato vs. aprendido y su (posible) superación / Les études du comportement, la dichotomie inné vs. appris et son (possible) dépassement

Resumo: O debate inato vs. aprendido continua presente na Academia, bem como na sociedade. Considerando tal cenário, este artigo apresenta o desdobrar das discussões que giram em torno das influências ambientais e genéticas, na gênese dos comportamentos. Para isso, primeiramente é apresentada uma reflexão acerca da definição de comportamento com a finalidade de apresentar o objeto da discussão, bem como a imprecisão em sua caracterização. Posteriormente, são destacadas as principais diferenças entre o pensamento behaviorista e o etológico, e em como essas diferenças impactaram a condução de pesquisas, além de sustentar discursos eugenistas e/ou discriminatórios. Por último, disserta-se sobre uma abordagem não-dicotômica ao tema, na forma dos Sistemas em Desenvolvimento, como uma proposta de superação do debate em questão.

Abstract: Given the remaining prominence of nature vs. nurture debate in academia and society, this article discusses environmental and genetic influences on the genesis of behavior. For this purpose, we first present the definition of behavior and discuss the imprecision in its characterization. Next, we examine the main differences between behaviorist and ethological thinking and their impact on research and on the support of eugenic discourses. To conclude, the article discusses a non-dichotomous approach to behavior based on the Developmental Systems Theory framework to overcome such dualism.

Resumen: El debate innato vs. aprendido permanece presente tanto en la academia como en la sociedad. Considerando este escenario, este artículo presenta el desarrollo de discusiones que giran en torno a las influencias ambientales y genéticas en la génesis del comportamiento. Para ello, en primer lugar, se presenta una reflexión sobre la definición de comportamiento con el fin de presentar el objeto de discusión, así como la imprecisión en su caracterización. Posteriormente, se destacan las principales diferencias entre el pensamiento behaviorista y el etológico, y su impacto en la realización de algunas investigaciones, además de fundamentarse en los discursos eugenésicos y/o discriminatorios. Para finalizar, este artículo discute un enfoque no dicotómico del tema, en la modalidad de Sistemas en Desarrollo, como propuesta para superar el debate en cuestión.

Résumé : Le débat inné vs. savant reste toujours présent dans l'Académie ainsi que dans la société. Au vu ce scénario, cet article discute des influences environnementales et génétiques sur la genèse du comportement. Pour ce faire, on reflète sur la définition du comportement et les imprécisions dans sa caractérisation pour ensuite explorer les principales différences entre la pensée béhavioriste et éthologique et leur impact sur certaines recherches et sur le soutien des discours eugéniques. L'article conclu par présentant une approche non dichotomique fondée sur la Developmental Systems Theory pour surmonter le débat en question.

Recent Advances in the Behavioral Ecology of European Plethodontid Salamanders.

There is a recent growing interest in the study of evolutionary and behavioral ecology of amphibians. Among salamanders, Plethodontidae is the most speciose family, with more than 500 species, while in Europe, there are only 8 species, all belonging to the genus Speleomantes. European plethodontids recently received increasing attention with regard to the study of their natural history, ecology and behavior; however, the lack of standardized data, especially for the latter, hampers comparative analysis with the species from the New World. We here synthetized the recent advances in Speleomantes behavioral ecology, considering as a starting point the comprehensive monography of Lanza and colleagues published in 2006. We identified the behavioral categories that were investigated the most, but we also highlighted knowledge gaps and provided directions for future studies. By reviewing the scientific literature published within the period 2006-2022, we observed a significant increase in the number of published articles on Speleomantes behavior, overall obtaining 36 articles. Behavioral studies on Speleomantes focused mainly on trophic behavior (42%), and on intraspecific behavior (33%), while studies on pheromonal communication and interspecific behavioral interactions were lacking. In addition, most of the studies were observational (83%), while the experimental method was rarely used. After providing a synthesis of the current knowledge, we suggest some relevant topics that need to be considered in future research on the behavioral ecology of European plethodontids, highlighting the importance of a more integrative approach in which both field observations and planned experiments are used.

Group-specific expressions of co-feeding tolerance in bonobos and chimpanzees preclude dichotomous species generalizations.

Bonobos are typically portrayed as more socially tolerant than chimpanzees, yet the current evidence supporting such a species-level categorization is equivocal. Here, we used validated group-level co-feeding assays to systematically test expressions of social tolerance in sixteen groups of zoo- and sanctuary-housed bonobos and chimpanzees. We found that co-feeding tolerance substantially overlaps between the species, thus precluding categorical inference at the species level. Instead, marked differences were observed between groups, with some bonobo communities exhibiting higher social tolerance than chimpanzee communities, and vice versa. Moreover, considerable intergroup variation was found within species living in the same environment, which attests to Pan's behavioral flexibility. Lastly, chimpanzees showed more tolerance in male-skewed communities, whereas bonobos responded less pronounced to sex-ratio variation. We conclude that the pervasive dichotomy between the tolerant bonobo and the belligerent chimpanzee requires quantitative nuance, and that accurate phylogenetic tracing of (human) social behavior warrants estimations of intraspecific group variation.

[Which place has experimentation in ethology?] / Quelle place pour l'expérimentation en éthologie ?

The experimental approach has been at the center of my thoughts since my baccalaureate of "experimental sciences". Trained in neurosciences, I very quickly chose the field of ethology, thinking I would escape certain experimental approaches and offer myself research more respectful of animal life. Today, I have to note that this option did not necessarily lead to what I had imagined. I have been both the witness and the actor of practices that deserve attention. This path, punctuated by an evolution of the conceptions of our relations with living beings, leads me to question the ethics, sometimes contradictory, of action and knowledge.

Title: Quelle place pour l'expérimentation en éthologie ? Abstract: La démarche expérimentale est au centre de mes réflexions depuis mon baccalauréat « sciences ex ¼. Formé aux neurosciences, j'ai très vite choisi l'éthologie de terrain, pensant échapper à certaines démarches expérimentales et m'offrir des activités de recherche plus respectueuses de la vie animale. Aujourd'hui, je dois constater que cette option n'aboutit pas forcément à ce que j'avais imaginé. J'ai été à la fois le témoin et l'acteur de pratiques qui méritent attention. Ce parcours, jalonné par une évolution des conceptions de nos relations avec les être animés, me conduit à questionner les éthiques, parfois contradictoires, de l'action et de la connaissance.

Endemic fish calling: Acoustics and reproductive behaviour of the Neretva dwarf goby Orsinigobius croaticus.

The Neretva dwarf goby Orsinigobius croaticus (Gobiiformes, Gobionellidae) is an endemic fish native to the freshwaters of the Adriatic Basin in Croatia and Bosnia and Herzegovina, a Mediterranean Biodiversity Hotspot. Due to its limited distribution range, specific karst habitat and endangered status, laboratory studies on reproductive biology are scarce but crucial. Herein, we investigated the sound production and acoustic behaviour of the endangered O. croaticus during reproductive intersexual laboratory encounters, utilising an interdisciplinary approach. We also performed dissections and micro-computed tomography (µCT) scanning of the pectoral girdle to explore its potential involvement in sound production. Finally, comparative acoustic analysis was conducted on sounds produced by previously recorded soniferous sand gobies to investigate whether acoustic features are species-specific. The endemic O. croaticus is a soniferous species. Males of this species emit pulsatile sounds composed of a variable number of short (~15 ms) consecutive pulses when interacting with females, usually during the pre-spawning phase in the nest, but also during courtship outside the nest. Pulsatile sounds were low-frequency and short pulse trains (~140 Hz, <1000 ms). Male visual behaviour rate was higher when co-occurring with sounds and females entered the male's nest significantly more frequently when sounds were present. Characteristic body movements accompanied male sound production, such as head thrust and fin spreading. Furthermore, µCT scans and dissections suggest that O. croaticus shares certain anatomical similarities of the pectoral girdle (i.e. osseous elements and arrangement of levator pectoralis muscles) to previously studied sand gobies that could be involved in sound production. Multivariate comparisons, using sounds produced by eight soniferous European sand gobies, effectively distinguished soniferous (and sympatric) species based on their acoustic properties. However, the discrimination success decreased when temperature-dependent features (sound duration and pulse repetition rate) were excluded from the analysis. Therefore, we suggest both spectral and temporal features are important for the acoustic differentiation of sand gobies.