1. Phyllostomid bats exhibit great diversity in skull size and morphology that reflects the degree of resource division and ecological overlap in the group. In particular, Stenodermatinae has high morphological diversification associated with cranial and mandibular traits that is associated with the ability to consume the full range of available fruits (soft and hard). In terms of morphology, performance (bite force) appears to play an important role in niche partitioning among bat species, however, very few studies have confirmed these relationships using functional cranial traits. 2. Here, we analyzed craniodental traits and their relationship to the bite force in 308 specimens distributed in seven species of stenodermatine bats with two foraging types: nomadic and sedentary frugivorous bats. We evaluated 19 functional traits of the skull and jaw related to feeding and bite force in live animals by correcting bite force with body size. We used a GLM model and post hoc tests to determine possible relationships and differences between cranial traits, species, and sex. 3. The results showed that there is significant interspecific variation between stenodermatines that are nomadic and sedentary. The greatest variation in bite force within species was explained by the mandibular toothrow length (MANDL) between sexes, which was greater in females. The larger species of Artibeus, together with Platyrrhinus helleri, Uroderma convexum and Sturnira giannae, which have a greater length of the skull, condylo-incisor, condylo-canine, mandibular toothrow and height of the coronoid, exhibit greater bite force. By contrast, the smaller species A. anderseni and A. phaeotis have short skulls and the lowest values of bite force, which suggests that the size of the skull confers a biomechanical advantage. 4. Our results highlight the usefulness of analyzing functional traits related to feeding to establish the performance of bats in terms of the bite force.

Diego Sierra

and 6 more

Arachnids are the most abundant land predators. Despite the importance of their functional roles as predators and the of necessity to understand their diet for conservation and nutrient fluxes, the trophic ecology of many arachnid species is not fully understood. In the case of the wandering spider, Phoneutria boliviensis F. O. Pickard-Cambridge, 1897, only selected field and laboratory observational studies about their diet exist. By using a DNA metabarcoding approach, we compared the prey found in the gut content of males and females from three distant Colombian populations of P. boliviensis. By DNA metabarcoding of the cytochrome c oxidase subunit I (COI), we detected and identified 234 prey records belonging to 96 operational taxonomic units (OTUs), as prey for this wandering predator. Our results broaden the known diet of P. boliviensis with at least 75 prey taxa not previously registered in fieldwork or laboratory experimental trials. These results suggest that P. boliviensis feeds predominantly on invertebrates (Diptera, Lepidoptera, Coleoptera and Orthoptera) and opportunistically on small squamates. Intersex and interpopulation differences are observed. Assuming that prey preference does not vary between populations, these differences are likely associated with a higher local prey availability. Finally, we suggest that DNA metabarcoding can be used for evaluating subtle differences in the diet of distinct populations of P. boliviensis, particularly when predation records in the field cannot be established or quantified using direct observation

Diego Sierra

and 6 more

Arachnids are the most abundant land predators. Despite the importance of their functional roles as predators and the of necessity to understand their diet for conservation and nutrient fluxes, the trophic ecology of many arachnid species is not fully understood. In the case of the wandering spider, Phoneutria boliviensis F. O. Pickard-Cambridge, 1897, only selected field and laboratory observational studies about their diet exist. By using a DNA metabarcoding approach, we compared the prey found in the gut content of males and females from three distant Colombian populations of P. boliviensis. By DNA metabarcoding of the cytochrome c oxidase subunit I (COI), we detected and identified 234 prey records belonging to 96 operational taxonomic units (OTUs), as prey for this wandering predator. Our results broaden the known diet of P. boliviensis with at least 75 prey taxa not previously registered in fieldwork or laboratory experimental trials. These results suggest that P. boliviensis feeds predominantly on invertebrates (Diptera, Lepidoptera, Coleoptera and Orthoptera) and opportunistically on small squamates. Intersex and interpopulation differences are observed. Assuming that prey preference does not vary between populations, these differences are likely associated with a higher local prey availability. Finally, we suggest that DNA metabarcoding can be used for evaluating subtle differences in the diet of distinct populations of P. boliviensis, particularly when predation records in the field cannot be established or quantified using direct observation