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In highly transformed regions, such as the tropical Andes, identifying the influence of forest succession and soil fauna on non-additive effects of litter decomposition is crucial for gaining a more realistic understanding of carbon dynamics and nutrient cycles. The objective of this paper was to analyze the changes of litter mixture effects on decomposition between different soil fauna treatments (macrofauna inclusion vs macrofauna exclusion) and successional stages (mature forests vs secondary forests) in upper Andean tropical forests along time by using a reciprocal translocation experiment of 1,344 litterbags that ran for 18 months with six common native Andean species. Thought t-tests, linear regressions, and linear mixed models, I found that litter mixture effects vary among sites and increase with time in secondary forests until the year of decomposition in litterbags with macrofauna exclusion. Mature forests exhibited strong antagonistic effects, while pronounced synergistic effects were observed in secondary forests. Although soil macrofauna did not increase significantly litter decomposition and synergistic effects in the mixtures at any of the stages of decay, it is likely that soil macrofauna may impact litter mixtures through top-down effects within soil food webs, rather than exerting a direct effect in the litter consumption as has been reported in tropical lowland ecosystems. Overall, this study supports the idea that litter mixtures exhibit significant variability across sites, can change with successional stage, and are influenced by soil fauna depending on the stage of decay in tropical Andean montane forests.

Sexual size dimorphism (SSD) is the difference in body size between males and females. One of the most studied patterns in allometric size difference between sexes is Rensch's rule, which describes an increase of SSD with increasing species size when males are the larger sex. However, few studies have tested this rule in bats, and morphological structures other than body size have rarely been included. The objective of this paper was to analyze the patterns of SSD across 28 New World bat species and assess their conformity to Rensch's rule. To do this, I obtained measurements of forearm length, length of the third digit, and length of the fifth digit from 1,151 bat specimens, and through t-tests and reduced major axis regressions, I analyzed patterns of SSD and Rensch's rule. I found high variation in size and wing morphology, with a modest female-biased size in more than half the species, which fails to support Rensch's rule. Larger wing structures in females can improve flight performance to overcome aerodynamic challenges during reproduction when carrying pups and foraging for food. Mechanisms other than body size in females, geographic variation, and the set of species selected may explain the isometric pattern between sexes, which invalidates Rensch's rule for Neotropical bats. Further studies should encompass a broader range of bat species from different lineages, but it is also necessary to analyze SSD based on various traits related to resource use, such as wing and nasal morphology, as well as include the influence of geographic variation and environmental factors. El dimorfismo sexual del tamaño (DST) es la diferencia en el tamaño corporal entre machos y hembras. Uno de los patrones mas estudiados en la diferencia de tamaño alométrico entre sexos es la regla de Rensch que describe un aumento del DST con el aumento del tamaño de la especie cuando los machos son el sexo más grande. Sin embargo, existen pocos estudios realizados en murciélagos y en contadas ocasiones se han incluido estructuras morfológicas distintas del tamaño corporal para probar esta regla. El objetivo de este artículo fue analizar los patrones de DST en 28 especies de murciélagos neotropicales y evaluar la validez de la regla de Rensch. Para ello, obtuve medidas de la longitud del antebrazo, longitud del tercer y quinto dígito de 1,151 especímenes de murciélagos, y a través de pruebas t y de regresiones de eje mayor reducido, analicé patrones de DST y la regla de Rensch. Encontré una gran variación en el tamaño y la morfología alar con un ligero aumento de las hembras en más de la mitad de las especies, lo cual no respalda la regla de Rensch. Estructuras alares más grandes en las hembras pueden mejorar el rendimiento de vuelo para superar los desafíos aerodinámicos durante la reproducción cuando cargan a las crías y buscan alimento. Mecanismos distintos del tamaño corporal en las hembras, así como la variación geográfica, y el conjunto de especies seleccionadas pueden explicar el patrón de isometría entre sexos que invalida la regla de Rensch para murciélagos neotropicales. Futuros estudios deberían abarcar una mayor variedad de especies de murciélagos de diferentes linajes, pero también es necesario analizar el DST en función en diversos rasgos relacionados con el uso de recursos, como la morfología alar y nasal, además de incluir la influencia de la variación geográfica y los factores ambientales. [ABSTRACT FROM AUTHOR]

Wood density (WD) is a key functional trait related to ecological strategies and ecosystem carbon dynamics. Despite its importance, there is a considerable lack of information on WD in tropical Andean forests, particularly regarding its relationship with forest succession and ecosystem carbon cycling. Here, we quantified WD in 86 upper Andean tree and shrub species in central Colombia, with the aim of determining how WD changes with forest succession and how it is related to productivity. We hypothesized that WD will increase with succession because early successional forests will be colonized by acquisitive species, which typically have low WD, while the shaded understory of older forests should favor higher WD. We measured WD in 481 individuals from 27 shrub and 59 tree species, and quantified aboveground biomass (AGB), canopy height, net primary production (NPP) and species composition and abundance in 14, 400-m², permanent plots. Mean WD was 0.513 ± 0.114 (g/cm³), with a range between 0.068 and 0.718 (g/cm³). Shrubs had, on average, higher WD (0.552 ± 0.095 g/cm³) than trees (0.488 ± 0.104 g/cm³). Community weighted mean WD (CWMwd) decreased with succession (measured as mean canopy height, AGB, and basal area); CWMwd also decreased with aboveground NPP and stem growth. In contrast, the percentage of NPP attributed to litter and the percent of shrubs in plots increased with CWMwd. Thus, our hypothesis was not supported because early successional forests had higher CWMwd than late successional forests. This was related to a high proportion of shrubs (with high WD) early in succession, which could be a consequence of: 1) a low seed availability of trees due to intense land use in the landscape and/or 2) harsh abiotic conditions early in succession that filter out trees. Forest with high CWMwd had a high %NPP attributed to litter because they were dominated by shrubs, which gain little biomass in their trunks. Our findings highlight the links between WD, succession and carbon cycling (biomass and productivity) in this biodiversity hotspot. Thus, WD is an important trait that can be used to understand upper Andean forest recovery and improve forest restoration and management practices. [ABSTRACT FROM AUTHOR]

Bats are natural reservoirs of protozoal, viral, fungal and bacterial pathogens. However, little has been described about their endoparasites, especially in the Neotropics, despite the fact that this region represents a high taxonomic and functional bat diversity. In this study, we describe gastrointestinal parasites found in faecal samples of Neotropical bats from the Amazon rainforest of Colombia. We characterise the prevalence of parasites by employing flotation and McMaster techniques. We obtained 222 samples, but only 15 bats (6.8%) of the species Carollia brevicauda (n = 9), C. perspicillata (n = 3), Artibeus planirostris (n = 1), A. lituratus (n = 1) and Gardnerycteris crenulatum (n = 1) were positive for gastrointestinal parasites. This is the first survey of bat gastrointestinal parasites conducted in the Colombian Amazon. We report for the first time coccidian parasites in phyllostomid bats from Colombia. We also found nematodes in gestating females, which may suggest a transfer of parasites to the foetus during pregnancy in fruit bats. Besides insectivorous bats, frugivores can also represent a source for gastrointestinal parasites in the Neotropics, but the factors that determine their hosting capacity are still not fully understood. Further research should explore the interactions of wild and domestic hosts with parasites, which could be useful for analysing potential risks to the human population. [ABSTRACT FROM AUTHOR]

Bergmann's rule is one of the most vigorously debated ecogeographic patterns but has rarely been examined in Neotropical bats. Herein, I examined Bergmann's rule in Carollia perspicillata and Artibeus lituratus along an elevation gradient of 2500 m at both inter- and intraspecific level. I measured 384 specimens from collections belonged to C. perspicillata (89 ♀, 102 ♂) and A. lituratus (89 ♀, 104 ♂). The size of C. perspicillata increased with increasing elevation and decreasing temperature, whereas A. lituratus showed the converse pattern. For both species, females did not differ between elevation categories, contrary to males that were larger above 1000 m in C. perspicillata, but smaller in A. lituratus. Conformity to Bergmann's rule depends on bat size and sex. Despite C. perspicillata follows the pattern, the explanatory mechanisms still need to be understood. By contrast, A. lituratus follows the converse of Bergmann's rule due to naked and highly vascularized wings that aid thermoregulation in warmer environments. Male size is more sensitive to changes in temperature for both species which may be partially explained by sexual selection. Elevation and temperature are not the only factors related to bat morphology and other mechanisms may explain size in bats. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Along with habitat transformation, climate change has profound impacts on biodiversity and may alter ecosystem services on which human welfare depends. Many studies of the carbon cycle have focused on lowland tropical forests; however, upland forests have been less explored despite their pivotal role in carbon sequestration. Here, I synthesized the state of knowledge on the allocation of carbon in its different stocks (aboveground, belowground, and soil) as well as in its main fluxes (plant decomposition, respiration, and litterfall) in tropical upland ecosystems of the planet. In November 2020, a systematic review was carried out to identify references published from 2000 to 2020 through a combination of key terms in Google Scholar and Scopus databases, thus analysing bibliographic, geographical, methodological, and carbon cycling information of the global upland tropics (between 23.5 ∘ N–23.5 ∘ S). After analysing a total of 1967 references according to inclusion–exclusion criteria, 135 references published in the last 20 years were selected. Most of the studies were conducted in the tropical and subtropical moist broadleaf forest of South America. The main factors studied were elevation and forest type. Forest structure and soil variables were largely associated when studying carbon cycling in these ecosystems. Estimations of carbon stocks comprised three-fourths of the total studies, while the remaining fraction focused on carbon fluxes. Aboveground biomass and carbon in soils were highly investigated, while plant decomposition and respiration were the components that received the least attention. Even though in the last 20 years there was a slight increase in the number of studies on carbon cycle in tropical upland forests, I found bias associated with the biomes and ecoregions studied (especially in the Andes). Elevation was the main factor examined but other essential aspects such as the successional gradient, landscape management, diversity–productivity relationship, faunal and microbial effect, trophic cascades, and Gadgil effect require more attention. The inclusion of different litter species and origins (i.e. roots and stems) and theoretical frameworks including home-field advantage, substrate–matrix interaction, and phenology–substrate match may provide explanatory mechanisms to better understand litter decomposition over these forests. Despite respiration being a paramount link that is closely tied to above- and belowground compartment, this flux constitutes one of the important gaps to fulfil in future research. For a comprehensive understanding of the carbon cycle in upland forests, it is necessary to obtain information on its main fluxes and integrate them into climate change mitigation plans. [ABSTRACT FROM AUTHOR]

The surge of oil palm production in the Neotropics has become a major concern about the potential impacts on biodiversity. In the Colombian Orinoquia, which has shown a massive landscape transformation due to the growth of oil palm plantations, the effects of oil palm agriculture on bats in this region have not been studied up to date. To understand the impact of habitat conversion on bat diversity, we characterised bat assemblages in secondary forest and palm plantations in the Colombian Llanos foothills (Meta, Colombia). We captured 393 individuals (forest = 81, plantation = 312) of 18 species and 3 families. The forest cover presented three exclusive species while the plantation had five. Species diversity (q1) and evenness (J') were higher in the forest compared to the plantation. These differences derived from the increase in abundances of generalist species (Artibeus sp., Carollia spp.) in the plantation. Despite the habitat simplification caused by oil palm plantations, this monoculture provides a cover that is used by some bats, decreasing their risk of predation and allowing movement between patches of forest habitat as steppingstones. Maintaining forest cover in agricultural landscapes favours diversity by generating a "spillover effect" of the forest towards plantations, which in the case of some bats contributes to the reduction of species isolation and the maintenance of ecosystem services provided by them. It is important to improve management practices of oil palm plantations to minimise negative impacts on biodiversity, considering the expansion of this productive system and the scarcity of protected areas in this region. [ABSTRACT FROM AUTHOR]

Dietary studies of insectivorous bats are critical for a comprehensive analysis of their ecological role in pest control. Several factors including seasonality, reproductive status and sex may influence dietary specialization. However, data on insectivorous bat diet are scarce, especially in Mormoopidae family. Here, we analyzed the dietary variation of Mormoops megalophylla (Peters, 1864) between sexes, reproductive states and climatic seasons in Macaregua cave, located in Northeastern Andes of Colombia. We collected fecal samples and vaginal smears from 377 individuals. We assess differences between sexes in the frequency of insect consumption and we estimate dietary breadth in reproductive and non-reproductive bats. Moormops megalophylla has a highly specialized diet, selecting primarily for Lepidoptera insects. There were no differences between sexes, but wider dietary breadth was found in reproductive bats in comparison to non-reproductive bats. Probably, the specialization on Lepidoptera insects is explained by the high amounts of caloric energy that these insects can offer. It was remarkable the upward trend in Lepidoptera consumption from reproductive bats during the wet season, when moths are available. By contrast, non-reproductive bats increased Lepidoptera consumption in the dry season, possibly to prepare for the next reproductive events. The analysis of diet over time suggests variations between climatic seasons and reproductive states; that is, when bats are reproductively active, they increase the amount of Lepidoptera consumption in the wet season to supply their energy requirements during reproduction. These results provide key information about the ecology of M. megalophylla in the northern part of its South American distribution. [ABSTRACT FROM AUTHOR]

Copyright of Therya is the property of Asociacion Mexicana de Mastozoologia, A. C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Colombian Orinoquia region is characterized by a high diversity of mammals, which is associated with complex ecosystems that include large extensions of Neotropical savannas (known locally as "Llanos Orientales"). Despite accelerated anthropogenic transformations in savanna ecosystems, the knowledge to design effective conservation strategies, such as the distribution of mammal assemblages, is still lacking for this region. In this paper, we evaluate if assemblages of medium and large mammals (i.e., species richness, relative abundance and the contribution of the different trophic guilds) are homogeneous across the Colombian Llanos by comparing three savanna ecosystems: floodplains savannas associated with an Andean river, aeolian floodplains savannas and highland savannas. After a sampling effort of 3,150 camera trap/days, we recorded 16 mammal species from the three savanna ecosystems. We compared the three assemblages and their constituent trophic guilds by ANOSIM and SIMPER non-parametric permutation tests. The three assemblages differed in composition, structure and trophic guilds. The floodplains savannas, associated to an Andean river, present the highest diversity, contrastingly, the high-plain associated with the Guyanese Shield presents the lowest diversity. This pattern could be explained due to the greatest floristic diversity, complex vegetation structure and more fertile soils present in the riparian forests of the floodplains savannas, despite being the most anthropogenically transformed. The carnivores were the most variable category and herbivores were the most abundant. Our results show that the diversity of medium and large mammals is heterogeneously distributed in the Colombian Llanos. Therefore, it is necessary to implement targeted conservation strategies according to the characteristics, local fragility of each ecosystem in the territory and each species response by local conditions. [ABSTRACT FROM AUTHOR]

Copyright of Neotropical Biology & Conservation is the property of Pensoft Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Neotropical Biology & Conservation is the property of Pensoft Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)