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Abstract We explore the use of movable automata in numerical modelling of male competition for territory. We used territorial dragonflies as our biological inspiration for the model, assuming two types of competing males: (a) faster and larger males that adopt a face‐off strategy and repulse other males; (b) slower and smaller males that adopt a non‐aggressive strategy. The faster and larger males have higher noise intensity, leading to faster motion and longer conservation of motion direction. The velocity distributions resemble the Maxwell distributions of velocity, expected in Brownian dynamics, with two probable velocities and distribution widths for the two animal subpopulations. The fast animals' trajectories move between visually fixed density folds of the slower animal subpopulation. A correlation is found between individual velocity and individual area distribution, with smaller animals concentrated in a region of small velocities and areas. Attraction between animals results in a modification of the system behaviour, with larger animals spending more time being surrounded by smaller animals and being slowed down by their interaction with the surroundings. Overall, the study provides insights into the dynamics of animal competition for territory and the impact of attraction between animals.

The breeding of captive wild species can play a crucial role in their preservation. Jaguars, the largest felines in the Americas, face challenges in captivity that hinder their breeding success in zoos and conservation institutions. One major barrier to successful captive breeding is the difficulty of replicating the natural environment, including nutritional, social, and habitat needs. Hence, any insights into the breeding behaviour and parental care of jaguars can inform and enhance breeding strategies for these captive felines. In this study, we aimed to examine maternal behaviours during the pre- and post-partum periods in the first successful case of natural reproduction of captive jaguars in Brazil. The study took place at the Mata Ciliar Association in Jundiaí , Brazil, where infrared cameras were used to observe maternal behaviours without human interference. The behaviours were analysed using an ethogram of the mother and Generalized Linear Models (GLM) to examine her behavioural repertoire during three different phases of parental care. Our findings suggest that there were differences in the behaviours exhibited by the female jaguar in the pre- and post-partum periods. Furthermore, the mother's interactions with her jaguar cubs reduced her stereotyped behaviours, implying an improvement in her welfare. Finally, we offer suggestions and recommendations to facilitate future breeding efforts for captive jaguars.

The damselflies Hetaerininae, a subfamily of Calopterygidae, comprise four genera distributed from North to South America: Hetaerina, Mnesarete, Ormenophlebia and Bryoplathanon. While several studies have focused on the intriguing behavioral and morphological modifications within Hetaerina, little of the evolutionary history of the group is well understood. Understanding the biogeographical history of Hetaerininae is further complicated by uncertainty in important geological events, such as the closure of the Central American Seaway (CAS). We generated a phylogenetic hypothesis to test the relationships and divergence times within Hetaerininae using IQtree and BEAST2 and found that Mnesarete and Ormenophlebia render Hetaerina paraphyletic. Reclassification of the genera within Hetaerininae is necessary based on our results. We also tested the fit to our dataset of two different hypotheses for the closure of CAS. Our results supported a gradual closure, starting in the Oligocene and ending in the Pliocene. Using Ancestral Character State Reconstruction, we found that the rubyspot, which is associated with higher fecundity in several species, was ancestral for Hetaerininae and subsequently lost four times. Estimates of diversification in association with the rubyspot are needed to understand the plasticity of this important character. Forest habitat was the ancestral state for Hetaerininae, with transitions to generalist species of Hetaerina found primarily in the Mesoamerican region. These results add to our understanding of the relationship between morphology, biogeography and habitat in a charismatic group of damselflies.

The genus Franciscobasis Machado & Bedê, 2016 is endemic to the Serra da Canastra National Park in Minas Gerais state, Brazil. Two species of Franciscobasis were described simultaneously with the genus description: F. franciscoi and F. sonia, the latter described only from females. Through morphological and molecular analysis, we investigated if F. sonia may represent the young female of F. franciscoi. Resulting data did not present adequate differences between females to characterize them as different species. Therefore, we suggest that F. sonia is a junior synonym of F. franciscoi, and the female of F. franciscoi goes through a complex ontogenetic color change.

Pericarpial nectaries (PNs) have frequently been treated in the literature as extrafloral nectaries (EFNs). This treatment is partly justified by their morphological and functional similarities in attracting bodyguard ants to protect the plant against herbivores. Palicourea rigida is a common Neotropical savanna treelet with tubular yellow flowers that are pollinated by hummingbirds. After pollination, the corolla falls, but the sepal ring remains and keeps the nectaries active over the ovarium throughout fruit development stages. Using a standard ant-exclusion experiment, we tested whether these PNs attract ants to protect the developing fruits against seed parasites and the leaves against chewing herbivores. We analyzed the differences between the initial and final leaf area. Before full fruits maturity, they were collected and taken to the laboratory for weighing and to observe wasp emergence. The number of wasps per fruit and per plant was recorded. The results showed that after pollination, the floral nectaries of P. rigida act as EFNs, attracting visiting ants. Ant-tended plants lost significantly less leaf area and had heavier fruits than untended plants. However, the ants did not protect the fruits against seed-parasitic wasps. In P. rigida, the post-floral secretions of PNs play the same role as EFNs, and the ant-plant mutualism is context-dependent based on the type of herbivore and the plant tissue consumed.

Assassin bugs (Reduviidae) are voracious insects that prey on other arthropods. Recent evidences have pointed out that these predators also feed on plant derived substances in rare opportunities. The present study describes the feeding behavior of the reduviid Atopozelus opsimus on extrafloral nectaries of Inga vera (Fabaceae) in a Neotropical savanna area. It was investigated if the insects feed more frequently of extrafloral nectar or prey, and if individuals of different stages of development vary according to feeding behavior. Notably, the results suggest that the diet of all instars and adults consist mainly of extrafloral nectar (N = 1013), in detriment of captured prey ingestion (N = 18). Also, there was no variation on feeding behavior and life stage.

Conspecific density may influence adult recruitment and consequently population dynamics. Several studies have shown the density dependence of larvae growth rates in Odonata. However, few studies studied how conspecific density influence final instar larvae emergence date decisions. Considering that larvae may choose the date of emergence, the present study investigated if density affects larvae choice. For this, we reared eight final instar larvae in individual aquaria and other 24 larvae in aquaria with three larvae each. This way, we simulated environments with low and high larval densities. We then noted the days that larvae took to emerge and compared it between low and high density groups. The results showed that larvae seem to emerge earlier when in high densities (Mann-Whitney, U=10.000, P=0.03). These results support the hypothesis that damselfly last instar larvae may postpone or hasten emergence in response to the social environment and related constraints.

Sexual and species recognition, along with sexual color dimorphism, play an important role in the reproduction of many animal species. In this article, it was investigated if males of the dimorphic Neotropical damselfly Acanthagrion truncatum are able to recognize mates and differentiate them between co-specific males and hetero-specific females of sympatric species. The results showed misguided mating attempts from males towards other males and Homeoura chelifera females. They also seem able to recognize A. lancea and Telebasis carmesina females as hetero-specifics. This study support the hypothesis that male-male interactions are misdirected sexual behavior and that sympatric morphologically similarspecies may represent visual interference for mate searching males.

Abstract Insect coloration has evolved in response to multiple pressures, and in Odonata (dragonflies and damselflies) a body of work supports a role of wing color in a variety of visual signals and potentially in thermoregulation. Previous efforts have focused primarily on melanistic coloration even though wings are often multicolored, and there has yet to be comprehensive comparative analyses of wing color across broad geographic regions and phylogenetic groups. Percher vs. flier flight-style, a trait with thermoregulatory and signaling consequences, has not yet been studied with regard to color. We used a new color clustering approach to quantify color across a dataset of over 8,000 odonate wing images representing 343 Nearctic species. We then utilized phylogenetically informed Bayesian zero-inflated mixture models to test how color varies with mean ambient temperature, body size, sex and flight-style. We found that wing coloration clustered into two groups across all specimens - light brown-yellow and black-dark brown - with black-dark brown being a much more cohesive grouping. Male perchers have a greater proportion of black-dark brown color on their wings as do species with longer wings. In colder climates, odonates were more likely to have black-dark brown color present, but we found no relationship between the proportion of black and temperature. Light brown-yellow showed similar scaling with wing length, but no relationship with temperature. Our results suggest that black-dark brown coloration may have a limited role in thermoregulation, while light brown-yellow does not have such a role. We also find that the odonate sexes are divergent in wing color in percher species only, suggesting a strong role for color in signaling in more territorial males. Our research contributes to an understanding of complex interactions driving ecological and evolutionary dynamics of color in animals.

Trophobiosis between ants and homopterans is widely known. Nevertheless, this interaction can also happen between treehoppers and other animals in a non-mutualistic way. For instance, here we observed the wasp Pseudopolybia vespiceps (Hymenoptera: Vespidae) collecting honeydew flickered by Aethalion reticulatum (Hemiptera: Cicadomorpha) as an alternative food resource. Fieldwork was conducted during three consecutive days, when we made ad libitum behavioral observations using video footage. We noted the behavior of P. vespiceps when collecting honeydew from A. reticulatum. Strikingly, our observations resulted in the description of novel wasp behavior. The wasps compete with ants for access to treehoppers by kicking them out of the plant. Studies like this contribute to the understanding of trophic nets that depend on hemipteran honeydew.

Studies concerning the occurrence of species and seasonality are of great importance for both the elucidation of species distribution and conservation of natural habitats. We performed a survey of Odonata species and studied their seasonality in an endemic endangered palm swamp (i.e. Veredas) environment of the Ecological Reserve of Clube de Caça e Pesca Itororó de Uberlândia, Southestern Brazil. Between July 2010 and June 2011, we recorded 31 species of five different families and 21 genera. The community was strongly seasonal, since 24 species occurred in the wet season, while ten occurred in both dry and wet season, and only two species occured only in the dry season. All Anisoptera species preferred lentic habitats, whereas seven of the 18 Zygopera species preferred lentic habitats and 11 species preferred lotic sites. The five Calopterygidae and Protoneuridae species preferred lotic habitats. The study site exhibits a great diversity of dragonflies and damselflies, which are important elements of the trophic chain in the Cerrado aquatic and neighboring land environments. This justifies the development of conservation actions in palm swamp areas, which are poorly known and threatened by the constant advance of urban, monoculture and pasture areas in Cerrado.