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To define the chances of a dispersed seed to produce a new recruit, it is essential to consider all stages of the dispersal process. Howler monkeys are recognized to have positive impacts on forest regeneration, acting as primary dispersers. Furthermore, dung beetles attracted to their feces protect the seeds against predators, and provide a better microenvironment for germination due to the removal of fecal matter, to seed burial, and/or by reducing the spatial aggregation of seeds in fecal clumps.Despite the recognized positive effects of primary seed dispersal through defecation by howler monkeys for plant recruitment, there are some important aspects of their behavior, such as the habit of defecating in latrines, that remain to be explored.Here, we investigated the fate of Campomanesia xanthocarpa seeds defecated by brown howlers, Alouatta guariba clamitans, and the secondary seed dispersal by dung beetles, considering how this process is affected by the monkey's defecation patterns. We found that brown howler monkeys dispersed seeds from several species away from fruit-feeding trees, partly because defecation under the canopy of such trees was not very frequent. Instead, most defecations were associated with latrines under overnight sleeping trees. Despite a very similar dung beetle community attracted to howler feces in latrines and fruit-feeding sites, seeds were more likely to be buried when deposited in latrines. In addition, C. xanthocarpa seeds showed higher germination and establishment success in latrines, but this positive effect was not due to the presence of fecal matter surrounding seeds. Our results highlight that A. guariba clamitans acts as a legitimate seed disperser of C. xanthocarpa seeds in a preserved context of the Brazilian Atlantic Forest and that defecations in latrines increase the dispersal effectiveness.

Habitat loss and fragmentation have been leading jaguars to constant conflicts with humans, and as a result, jaguar populations have been declining over the last decades. Captive breeding is often a tool for species conservation, and it is not different for jaguars. However, success is far from optimal due to the lack of basic knowledge about species’ reproductive biology. In the present study, we assessed gonadal hormonal profiles of natural oestral cycles and puberty and compared our data to those of other wild felids. We collected faecal samples from two to seven times per week for 18 months from two adults and three pre-pubertal females. We defined baseline levels for progestins and oestrogens in order to estimate oestrous cycle length and age at puberty. We compared our data with 16 other species through generalized linear model, using weight and genus as two explanatory variables. Cycle length was 38.28 ± 2.52 days, ranging from 25 to 44 days, while sexual maturity was attained within 22 months. Due to our analysis of both hormonal and behavioural data, there is a variation between this research from other studies that employed only behavioural observations. Such difference may be caused by the absence of behavioural oestrous at the peri-pubertal period. When compared to wild felids of similar size, puberty and oestral cycle durations of the jaguar females fell within the same range. Our modelling showed that age at maturity was influenced mostly by size and only Leopardus partially explained the observed variation. Conversely, oestral cycle length did not differ among genera or size categories. Our study adds to the body literature in the reproductive endocrinology of wild felids, and because female gametes are more challenging to collect and preserve, a strong understanding on the female reproductive physiology is essential to assisted reproduction and wild population viability assessment.

Mammals are generally brown in colour, but recent publications are showing that they may not be as uniform as once assumed. Monotremes, marsupials, and a handful of eutherians reflect various colours when lit with UV light, mostly purple. Because of these still scarce records, we aimed to explore UV reflectance among rodent genera, the most diverse mammalian group, and the group of eutherians with the most common records of biofluorescence. Here we report structures like nails and quills reflected green, but for most genera, it was faded. However, Hystrix, Erethizon, and Ctenomys showed intense and contrasting green glow, while Chaetomys presented a vivid orange anogenital. The main available explanation of fluorescence in mammals relies on porphyrin. This explanation applies to the cases like Chaetomys, where specimens showed anogenital orange biofluorescence, but does not apply to the green biofluorescence we observed. In our sample, because the structures that reflected green were all keratinized, we have reasons to believe that biofluorescence results from keratinization and is a structurally-based colouration. However, not all spines/quills equally biofluoresced, so we cannot rule out other explanations. Since Rodentia is the most common mammalian group with reports on biofluorescence, this trait likely serves various functions that match the species diversity of this group.

Disentangling the structure of plant–animal mutualisms shed light on how species are organized, and allow us to infer about resilience, specificity, and ultimately the consequences of the loss of functions to the ecosystem. Here we gathered fruit–frugivore interactions for all the major vertebrate taxa interacting with plants in two conservation states in the Brazilian Atlantic forest: a small patch and a continuous forest. Using a network approach, we identified individual roles played by vertebrates and plants, as well as the most relevant functional traits determining the network structure. The most important vertebrates in the continuous forest were the frugivorous characterized by the ability to swallow fruits containing small to large seeds, but they also were the first to be vanished from the small patch decades ago. Animal gape/gullet size, but not body mass, together with the greatest degrees of frugivory contributed to structure the conserved community. In the forest patch, where specialization degrees (in terms of number of interactions performed) were lost, small generalist birds and the only still living primate, along with small lipid‐rich fruits, were central in maintaining community structure. This study brings insights on the potential of conserved forests to hold important species‐rich interactions, at the same time that small patches count on small birds and small fruits with increased energetic rewards to maintain structuring under human degradation threats. Our results reemphasize the importance of preserving large continuous forest remnants to support important mutualistic interactions subjected to functional traits already lost in small degraded patches. Abstract in Portuguese is available with online material.

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