RESUMEN
Bats play crucial ecosystem services as seed dispersers, pollinators, controllers of insects, and nutrient recyclers. However, there has not been a thorough global review evaluating these roles in bats across all biogeographical regions of the world. We reviewed the literature published during the last two decades and identified 283 relevant studies: 78 dealt with the control of potential insect pests by bats, 80 related to the suppression of other arthropods, 60 on the dispersal of native or endemic seeds, 11 dealt with the dispersal of seeds of introduced plants, 29 on the pollination of native or endemic plants, 1 study on pollination of introduced plants, and 24 on the use of guano as fertilizer. Our literature search showed that queries combining the terms "seed dispersal," "insectivorous bats," "nectarivorous bats," "use of guano," and "ecosystem services" returned 577 studies, but half were experimental in nature. We found that the evaluation of ecosystem services by bats has been mostly conducted in the Neotropical and Palearctic regions. To detect differences across relevant studies, and to explain trends in the study of ecosystem services provided by bats, we performed generalized linear mixed models (GLMM) fitted with a Poisson distribution to analyze potential differences among sampling methods. We identified 409 bat species that provide ecosystem services, 752 insect species consumed by bats and 549 plant species either dispersed or pollinated by bats. Our review summarizes the importance of conserving bat populations and the ecological services they provide, which is especially important during the current pandemic.
Asunto(s)
Quirópteros , Ecosistema , Animales , Insectos , PolinizaciónRESUMEN
Bats in the family Phyllostomidae exhibit great diversity in skull size and morphology that reflects the degree of resource division and ecological overlap in the group. In particular, the subfamily Stenodermatinae has high morphological diversification associated with cranial and mandibular traits that are associated with the ability to consume the full range of available fruits (soft and hard).We analyzed craniodental traits and their relationship to the bite force in 343 specimens distributed in seven species of stenodermatine bats with two foraging strategies: nomadic and sedentary frugivory. We evaluated 19 traits related to feeding and bite force in live animals by correcting bite force with body size.We used a generalized linear model (GLM) and post hoc tests to determine possible relationships and differences between cranial traits, species, and sex. We also used Blomberg's K to measure the phylogenetic signal and phylogenetic generalized least-squares (PGLS) to ensure the phylogenetic independence of the traits.We found that smaller nomadic species, A. anderseni and A. phaeotis , have a similar bite force to the large species A. planirostris and A. lituratus; furthermore, P. helleri registered a bite force similar to that of the sedentary bat, S. giannae. Our study determined that all the features of the mandible and most of the traits of the skull have a low phylogenetic signal. Through the PGLS, we found that the diet and several cranial features (mandibular toothrow length, dentary length, braincase breadth, mastoid breadth, greatest length of skull, condylo-incisive length, and condylo-canine length) determined bite force performance among Stenodermatiane.Our results reinforce that skull size is a determining factor in the bite force, but also emphasize the importance of its relationships with morphology, ecology, and phylogeny of the species, which gives us a better understanding of the evolutionary adaptions of this highly diverse Neotropical bat group.
RESUMEN
In Neotropical bats, studies on bite force have focused mainly on differences in trophic ecology, and little is known about whether factors other than body size generate interspecific differences in bite force amongst insectivorous bats and, consequently, in their diets. We tested if bite force is related to skull morphology and also to diet in an assemblage of Neotropical insectivorous bats from tropical dry forests in the inter-Andean central valley in Colombia. It is predicted that the preference of prey types among insectivorous species is based on bite force and cranial characteristics. We also evaluated whether skull morphology varies depending on the species and sex. Cranial measurements and correlations between morphological variation and bite force were examined for 10 insectivorous bat species. We calculated the size-independent mechanical advantage for the mandibular (jaw) lever system. In all species, bite force increased with length of the skull and the jaw more than other cranial measurements. Obligate insectivorous species were morphologically different from the omnivorous Noctilio albiventris, which feeds primarily on insects, but also consumes fish and fruits. Our results show that bite force and skull morphology are closely linked to diets in Neotropical insectivorous bats and, consequently, these traits are key to the interactions within the assemblage and with their prey.
RESUMEN
RESUMEN El estudio mastozoológico del departamento del Tolima ha aumentado en los últimos años; sin embargo, esta información no ha sido compilada, ni actualizada, de manera que se identifiquen los errores de distribución y taxonómicos, en aras de identificar prioridades de investigación y de conservación. Con el fin de unificar la información de los mamíferos presentes en el departamento, se recopilaron y se validaron los registros museológicos de la Colección Zoológica de la Universidad del Tolima (CZUT-M), Museo Javeriano de Historia Natural Lorenzo Uribe (MPUJ), bases de datos de colecciones nacionales, internacionales e información bibliográfica. La lista de mamíferos consolidada confirma 126 especies, lo que equivale al 24,32% de las especies de mamíferos de Colombia, entre las cuales, se registra seis endémicas y siete en alguna categoría de amenaza. Esta diversidad, se agrupa en 30 familias, 88 géneros y 12 órdenes, en donde Chiroptera (71 spp.) y Rodentia (18 spp.) son los mejor representados. La zona de vida que evidenció la mayor riqueza de especies fue el Bosque Seco Tropical, con 56; no obstante, estas áreas han presentado un mayor esfuerzo investigativo en relación con otras, como las establecidas por encima de los 2.000m s.n.m. Se resalta la necesidad de investigaciones en el departamento, para complementar los vacíos de información, así como la implementación de planes de manejo y de conservación, tanto de las especies como de las áreas.
ABSTRACT The mastozoologica study of the department of Tolima has increased in recent years, however, this information has not been compiled, nor updated, so as to identify distribution and taxonomic errors in order to identify research and conservation priorities. In order to synthesize the information on mammals from this Department, here a compilation of information from voucher specimens from Colección Zoológica de la Universidad del Tolima (CZUT-M), Museo Javeriano de Historia Natural Lorenzo Uribe (MPUJ), national collections as well as records from international museum databases and the scientific literature were investigated. As product of our analyses, the list contains 126 species of mammals, a number which is equivalent to 24.32% of the mammal species of Colombia; of these species, six are endemic to the country and seven are in any category of threat. This diversity is grouped into 30 families, 88 genera and 12 order, of these Chiroptera (71 spp.) and Rodentia (18 spp.) are the best represented. The zone of life that presented the greatest richness of species was the Tropical Dry Forest with 56, however, these areas have presented a greater investigative effort in relation to others, such as those established above 2000m.a.s.l. Our work reveals the need of new efforts to fill out the mammalian information gaps, as well as management and conservation plans for species and areas.