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1.
Conserv Biol ; 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37937478

RESUMO

Multifunctional landscapes that support economic activities and conservation of biological diversity (e.g., cattle ranches with native forest) are becoming increasingly important, as small remnants of native forest may comprise the only habitat left for some wildlife species. Understanding the co-occurrence between wildlife and disturbance factors, such as poaching activity and domestic ungulates, is key to successful management of multifunctional landscapes. Tools to measure co-occurrence between wildlife and disturbance factors include camera traps and autonomous acoustic recording units. We paired 52 camera trap stations with acoustic recorders to investigate the association between two measures of disturbance (poaching and cattle) and wild ungulates present in multifunctional landscapes of the Colombian Orinoquía. We used joint species distribution models to investigate species-habitat associations and species-disturbance correlations. One model was fitted using camera trap data to detect wild ungulates and disturbance factors, and a second model was fitted after replacing camera-trap detections of disturbance factors with their corresponding acoustic detections. The direction, significance, and precision of the effect of covariates depended on the sampling method used for disturbance factors. Acoustic monitoring typically resulted in more precise estimates of the effects of covariates and of species-disturbance correlations. Association patterns between wildlife and disturbance factors were only found when disturbance was detected by acoustic recorders. Camera traps allowed us to detect non-vocalizing species whereas audio recording devices increased detection of disturbance factors leading to more precise estimates of co-occurrence patterns. The collared peccary, lowland tapir and white-tailed deer co-occurred with disturbance factors and are conservation priorities due to greater risk of poaching or disease transmission from cattle. Article impact statement: Co-occurrence of disturbance and wildlife depends on method of detection (camera traps or acoustic recorders). This article is protected by copyright. All rights reserved.

2.
Am J Bot ; 110(8): e16211, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37459470

RESUMO

PREMISE: Variation in fruit and seed traits could originate from selection pressures exerted by frugivores or other ecological factors (adaptive hypotheses) and developmental constraints (by-product hypotheses) or chance. METHODS: We evaluated fruit and leaf traits for nearly 850 plant species from a rainforest in Tinigua Park, Colombia. Through a series of linear regressions controlling for the phylogenetic signal of the traits (minimum N = 542), we tested (1) whether the allometry between seed width and length depends on seed dispersal system (Mazer and Wheelwright's adaptive hypothesis of allometry for species dispersed in the guts of animals = endozoochory) and (2) whether fruit length is associated with leaf length (i.e., Herrera's by-product hypothesis derived from the assumption that both organs develop from homologous structures). RESULTS: We found a strong negative allometric association between seed width and length for seeds of endozoochorous species, as expected; but also, for anemochorous species. We found a positive relationship between fruit and leaf length, but this relationship was not evident for zoochorous species. Fruit size was highly correlated with seed size. CONCLUSIONS: The allometry between seed length and width varied among dispersal systems, supporting that fruit and seed morphology has been modified by interactions with frugivores and by the possibility to rotate for some wind dispersed species. We found some support for the hypothesis on developmental constraints because fruit and leaf size were positively correlated, but the predictive power of the relationship was low (10-15%).


PREMISA: La variación en los rasgos de frutos y semillas de las plantas podría tener su origen en las presiones de selección ejercidas por los frugívoros u otros factores ecológicos (hipótesis adaptativas), así como en limitaciones del desarrollo (hipótesis de subproductos) o en el azar. MÉTODOS: Nosotros evaluamos rasgos de frutos y hojas en cerca de 850 especies de plantas de un bosque húmedo tropical en el Parque Nacional Natural Tinigua, Colombia. Usando una serie de regresiones lineales que controlan por la señal filogenética de dichos rasgos (mínimo N = 542), nosotros probamos (1) si la alometría entre el ancho y largo de la semilla depende del sistema de dispersión de la semilla (i.e., hipótesis adaptativa de Mazer y Wheelwright; en la que se espera una alometría negativa para especies dispersadas por endozoocoria) y (2) si el largo del fruto está asociado con el largo de la hoja (i.e., la hipótesis del subproducto de Herrera derivada de la suposición de que ambos órganos se desarrollan a partir de estructuras homólogas). RESULTADOS: Nosotros encontramos una fuerte asociación alométrica negativa entre el ancho y el largo de las semillas para las semillas de las especies endozoócoras, como era de esperar; pero también, para las especies anemócoras. Nosotros también hallamos una relación positiva entre el largo del fruto y de la hoja, pero esta relación no fue evidente para las especies endozoócoras. Detectamos que el tamaño del fruto esta altamente correlacionado con el tamaño de la semilla. CONCLUSIONES: La alometría entre el largo y el ancho de la semilla varió entre sistemas de dispersión, lo que sugiere que la morfología de frutos y semillas ha sido moldeada por interacciones con frugívoros en el caso de las semillas endozoócoras y por la posibilidad de rotar para algunas especies dispersadas por el viento. Aunque el poder predictivo de la relación entre el tamaño del fruto y de la hoja fue bajo (10-15%), nosotros encontramos un apoyo moderado a la hipótesis sobre las limitaciones del desarrollo, ya que el tamaño del fruto y de la hoja estaban correlacionados positivamente.


Assuntos
Frutas , Dispersão de Sementes , Animais , Frutas/anatomia & histologia , Floresta Úmida , Filogenia , Sementes/anatomia & histologia , Folhas de Planta
3.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210076, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36373921

RESUMO

Seed dispersal by animals is key for restoration of tropical forests because it maintains plant diversity and accelerates community turnover. Therefore, changes in seed dispersal during forest restoration can indicate the recovery of species interactions, and yet these changes are rarely considered in forest restoration planning. In this study, we examined shifts in the importance of different seed dispersal modes during passive restoration in a tropical chronosequence spanning more than 100 years, by modelling the proportion of trees dispersed by bats, small birds, large birds, flightless mammals and abiotic means as a function of forest age. Contrary to expectations, tree species dispersed by flightless mammals dominated after 20 years of regeneration, and tree richness and abundance dispersed by each mode mostly recovered to old growth levels between 40 and 70 years post-abandonment. Seed dispersal by small birds declined over time during regeneration, while bat dispersal played a minor role throughout all stages of succession. Results suggest that proximity to old growth forests, coupled with low hunting, explained the prevalence of seed dispersal by animals, especially by flightless mammals at this site. We suggest that aspects of seed dispersal should be monitored when restoring forest ecosystems to evaluate the reestablishment of species interactions. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Assuntos
Quirópteros , Dispersão de Sementes , Animais , Ecossistema , Florestas , Árvores , Sementes , Aves , Clima Tropical
4.
Sci Rep ; 12(1): 14364, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999220

RESUMO

Primates are very selective in the foods they include in their diets with foraging strategies that respond to spatial and temporal changes in resource availability, distribution and quality. Colombian woolly monkeys (Lagothrix lagotricha lugens), one of the largest primate species in the Americas, feed mainly on fruits, but they also eat a high percentage of arthropods. This differs from closely related Atelid species that supplement their diet with leaves. In an 11 month study, we investigated the foraging strategies of this endemic monkey and assessed how resource availability affects dietary selection. Using behavioural, phenological, arthropod sampling and metabarcoding methods, we recorded respectively foraging time, forest productivity, arthropod availability in the forest and arthropod consumption. Scat samples and capturing canopy substrates (i.e. moss, bromeliads, aerial insects) were used for assigning arthropod taxonomy. The most important resource in the diet was fruits (54%), followed by arthropods (28%). Resource availability predicted feeding time for arthropods but not for fruits. Further, there was a positive relationship between feeding time on fruits and arthropods, suggesting that eating both resources during the same periods might work as an optimal strategy to maximize nutrient intake. Woolly monkeys preferred and avoided some fruit and arthropod items available in their home range, choosing a wide variety of arthropods. Geometrid moths (Lepidoptera) were the most important and consistent insects eaten over time. We found no differences in the type of arthropods adults and juveniles ate, but adults invested more time foraging for this resource, especially in moss. Although woolly monkeys are generalist foragers, they do not select their food items randomly or opportunistically.


Assuntos
Artrópodes , Atelinae , Animais , Colômbia , Dieta , Comportamento Alimentar , Frutas , Insetos
5.
Sci Rep ; 11(1): 6522, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33753830

RESUMO

Microbiome is known to play an important role in the health of organisms and different factors such as diet have been associated with modifications in microbial communities. Differences in the microbiota composition of wild and captive animals has been evaluated; however, variation during a reintroduction process in primates has never been reported. Our aim was to identify changes in the bacterial composition of three individuals of reintroduced woolly monkeys (Lagothrix lagothricha) and the variables associated with such changes. Fecal samples were collected and the V4 region of the 16S rRNA gene was sequenced to determine gut microbial composition and functionality. Individual samples from released individuals showed a higher microbial diversity after being released compared to before liberation, associated with changes in their diet. Beta diversity and functionality analysis showed separation of samples from released and captive conditions and the major factor of variation was the moment of liberation. This study shows that intestinal microbiota varies depending on site conditions and is mainly associated with diet diversity. The intake of food from wild origin by released primates may promote a positive effect on gut microbiota, improving health, and potentially increasing success in reintroduction processes.


Assuntos
Atelinae/microbiologia , Bactérias/genética , Dieta , Microbioma Gastrointestinal/genética , Animais , Atelinae/genética , Atelinae/fisiologia , Bactérias/classificação , Ingestão de Alimentos/genética , Ingestão de Alimentos/fisiologia , Fezes/microbiologia , RNA Ribossômico 16S/genética
6.
Sci Rep ; 11(1): 420, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431959

RESUMO

The extinction of megafauna in the Neotropics is thought to have reduced the potential of large seeds to be dispersed over long distances by endozoochory (ingestion by animals), but some seed dispersal systems have not been considered. We describe the role of oilbirds (Steatornis caripensis) as seed dispersers, in terms of seed width and dispersal distance (using GPS tracking devices), and we compare with data reported for other animals. Oilbirds dispersed seeds up to 29 mm wide, with a mean dispersal distance of 10.1 km (range 0-47.6 km). Some components of seed dispersal by oilbirds are outliers compared to that of other frugivores, such as the relationship between maximum seed width and body weight (however, few other extant specialized frugivores are also outliers). Estimates of mean dispersal distance by oilbirds are the largest reported, and we confirm that some living frugivores currently fulfil roles of seed dispersers and ecosystem services previously assumed to be only performed by extinct species.


Assuntos
Comportamento Alimentar/fisiologia , Dispersão de Sementes/fisiologia , Estrigiformes/fisiologia , Animais , Evolução Biológica , Aves/classificação , Aves/fisiologia , Peso Corporal/fisiologia , Quirópteros , Ecossistema , Elefantes , Extinção Biológica , Peixes , Frutas , Haplorrinos
8.
Primates ; 61(3): 373-387, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31965380

RESUMO

Over the past 20 years, GPS collars have emerged as powerful tools for the study of nonhuman primate (hereafter, "primate") movement ecology. As the size and cost of GPS collars have decreased and performance has improved, it is timely to review the use and success of GPS collar deployments on primates to date. Here we compile data on deployments and performance of GPS collars by brand and examine how these relate to characteristics of the primate species and field contexts in which they were deployed. The compiled results of 179 GPS collar deployments across 17 species by 16 research teams show these technologies can provide advantages, particularly in adding to the quality, quantity, and temporal span of data collection. However, aspects of this technology still require substantial improvement in order to make deployment on many primate species pragmatic economically. In particular, current limitations regarding battery lifespan relative to collar weight, the efficacy of remote drop-off mechanisms, and the ability to remotely retrieve data need to be addressed before the technology is likely to be widely adopted. Moreover, despite the increasing utility of GPS collars in the field, they remain substantially more expensive than VHF collars and tracking via handheld GPS units, and cost considerations of GPS collars may limit sample sizes and thereby the strength of inferences. Still, the overall high quality and quantity of data obtained, combined with the reduced need for on-the-ground tracking by field personnel, may help defray the high equipment cost. We argue that primatologists armed with the information in this review have much to gain from the recent, substantial improvements in GPS collar technology.


Assuntos
Ecologia , Sistemas de Informação Geográfica/estatística & dados numéricos , Movimento , Primatas , Animais , Ecologia/métodos
9.
Biota Neotrop. (Online, Ed. ingl.) ; 20(3): e20160305, 2020. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153204

RESUMO

Abstract: Medium and large mammals are greatly affected by human activities, such as, habitat loss and hunting. In Colombia, these pressures have been most extensive in the dry and Andean forests. However, there is scare information available on the presence or abundance of these organisms for monitoring purposes. This study used photo-trapping cameras to determine the relative abundances of medium and large mammals in a mountain forest in the National Natural Park "Cueva de los Guacharos", Huila (Colombia). Additionally, we examined whether trail use by humans could affect the distribution of these organisms. The cameras were located every 500 meters along the trails in strategic locations. We obtained the relative abundance of 11 species, being medium-sized mammals the most frequent (Cuniculus paca, Dasyprocta punctata and Mazama rufina). We recorded the presence of mountain tapir (Tapirus pinchaque), dwarf red brocket (Mazama rufina) and oncilla (Leopardus tigrinus), which are found in a high threat category according to the IUCN. Activity patterns were reported for 4 different species including daytime, nocturnal and cathemeral activities. Finally, we concluded that large mammals avoided trails of frequent use, and although the relative abundance of mammals is not very high, this National Park is still supporting relevant biodiversity.


Resumo: Os mamíferos de porte médio e grande são fortemente afetados por atividades humanas, tais como a perda do seu habitat e a caça. Na Colômbia, essas pressões foram mais extensas em florestas secas e andinas. No entanto, há pouca informação disponível sobre a presença ou abundancia destes organismos para os processos de monitoramento. Este estudo usou câmeras com mecanismos remotos de "armadilhas-fotográficas" (photo-trapping) para determinar a abundância relativa de mamíferos de porte médio e grande numa floresta de montanha no Parque Nacional Natural "Cueva de los Guacharos", Huila Colômbia. Adicionalmente, examinamos se o uso das trilhas pelos humanos poderia afetar a distribuição destes organismos. As câmeras foram localizadas a cada 500 metros ao longo das trilhas e em locais estratégicos. Obtivemos a abundância relativa de 11 espécies, sendo os mamíferos de médio porte os mais frequentes (Cuniculus paca, Dasyprocta punctata and Mazama rufina). Se registrou a presença do tapir da montanha (Tapirus pinchaque), do veado vermelho (Mazama rufina) e do gato-do-mato (Leopardus tigrinus), que fazem parte da categoria de espécies em ameaça de acordo com a IUCN. Os padrões de atividade das 4 espécies diferentes foram relatados, incluindo atividades diurnas, noturnas e atividades cathemeral. Por fim, concluiu-se que os grandes mamíferos evitam as trilhas de uso frequente, e embora a abundância relativa de mamíferos não seja muito alta, este parque nacional ainda tem uma biodiversidade proeminente.

10.
Folia Primatol (Basel) ; 90(4): 240-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31067556

RESUMO

The woolly monkey's (Lagothrix lagotricha) diet consists primarily of fruits, and for some populations fruit availability predicts its frequency in the diet. Woolly monkeys also eat new leaves, flowers, seeds and arthropods, but it is unclear whether arthropods are consumed in proportion to their environmental availability. We tested the hypothesis that arthropod consumption by woolly monkeys depends on availability. We studied a group of woolly monkeys for 10 months in 2013-2014, in Cueva de los Guácharos National Park, Colombia, in order to test the hypothesis that arthropod consumption by woolly monkeys depends on availability. We carried out surveys of plant phenology each month for 10 months to estimate fruit productivity, and every 2 months we also surveyed 3 canopy substrates (leaves, mosses and bromeliads) to quantify variation in arthropod biomass. During this time, we also quantified the diet of a woolly monkey group. The items most consumed were fruits (60%), followed by arthropods (24%), leaves (13%) and miscellaneous other items (3%). Arthropod biomass in the canopy did not vary considerably over the 10 months (0.014-0.037 g/g substrate) but was lower at the end of the second rainy season. A positive correlation was found between availability and entomophagy, but only when arthropods were relatively abundant. We did not find a relationship between arthropod and fruit feeding frequencies. Our results indicate that arthropods are prevalent in the diet of the woolly monkeys due to their abundance in Andean forest canopies.


Assuntos
Artrópodes , Atelinae/fisiologia , Dieta , Comportamento Alimentar , Cadeia Alimentar , Frutas , Animais , Colômbia , Feminino , Masculino , Densidade Demográfica
11.
Sci Rep ; 7(1): 14406, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089504

RESUMO

The uneven representation of frugivorous mammals and birds across tropical regions - high in the New World, low in Madagascar and intermediate in Africa and Asia - represents a long-standing enigma in ecology. Several hypotheses have been proposed to explain these differences but the ultimate drivers remain unclear. Here, we tested the hypothesis that fruits in Madagascar contain insufficient nitrogen to meet primate metabolic requirements, thus constraining the evolution of frugivory. We performed a global analysis of nitrogen in fruits consumed by primates, as collated from 79 studies. Our results showed that average frugivory among lemur communities was lower compared to New World and Asian-African primate communities. Fruits in Madagascar contain lower average nitrogen than those in the New World and Old World. Nitrogen content in the overall diets of primate species did not differ significantly between major taxonomic radiations. There is no relationship between fruit protein and the degree of frugivory among primates either globally or within regions, with the exception of Madagascar. This suggests that low protein availability in fruits influences current lemur communities to select for protein from other sources, whereas in the New World and Old World other factors are more significant in shaping primate communities.


Assuntos
Evolução Biológica , Frutas/metabolismo , Nitrogênio/metabolismo , Primatas , Animais , Dieta , Madagáscar , Primatas/fisiologia
12.
PLoS One ; 12(3): e0171072, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28301482

RESUMO

Understanding and predicting the likely response of ecosystems to climate change are crucial challenges for ecology and for conservation biology. Nowhere is this challenge greater than in the tropics as these forests store more than half the total atmospheric carbon stock in their biomass. Biomass is determined by the balance between biomass inputs (i.e., growth) and outputs (mortality). We can expect therefore that conditions that favor high growth rates, such as abundant water supply, warmth, and nutrient-rich soils will tend to correlate with high biomass stocks. Our main objective is to describe the patterns of above ground biomass (AGB) stocks across major tropical forests across climatic gradients in Northwestern South America. We gathered data from 200 plots across the region, at elevations ranging between 0 to 3400 m. We estimated AGB based on allometric equations and values for stem density, basal area, and wood density weighted by basal area at the plot-level. We used two groups of climatic variables, namely mean annual temperature and actual evapotranspiration as surrogates of environmental energy, and annual precipitation, precipitation seasonality, and water availability as surrogates of water availability. We found that AGB is more closely related to water availability variables than to energy variables. In northwest South America, water availability influences carbon stocks principally by determining stand structure, i.e. basal area. When water deficits increase in tropical forests we can expect negative impact on biomass and hence carbon storage.


Assuntos
Biomassa , Florestas , Temperatura , Clima Tropical , Água , Modelos Teóricos , América do Sul
13.
Ecology ; 98(5): 1474, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28241375

RESUMO

Wood density, or more precisely, wood specific gravity, is an important parameter when estimating aboveground biomass, which has become a central tool for the management and conservation of forests around the world. When using biomass allometric equations for tropical forests, researchers are often required to assume phylogenetic trait conservatism, which allows us to assign genus- and family-level wood specific gravity mean values, to many woody species. The lack of information on this trait for many Neotropical plant species has led to an imprecise estimation of the biomass stored in Neotropical forests. The data presented here has information of woody tissue specific gravity from 2,602 individual stems for 386 species, including trees, lianas, and hemi-epiphytes of lowland tropical forests in Colombia. This data set was produced by us collecting wood cores from woody species in five localities in the Orinoco and Magdalena Basins in Colombia. We found lower mean specific gravity values in várzea than in terra firme and igapó.


Assuntos
Plantas/química , Biomassa , Florestas , Filogenia , Gravidade Específica , Clima Tropical , Madeira
14.
Oecologia ; 183(2): 327-335, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27665543

RESUMO

The phylogenetic community assembly approach has been used to elucidate the role of ecological and historical processes in shaping tropical tree communities. Recent studies have shown that stressful environments, such as seasonally dry, white-sand and flooded forests tend to be phylogenetically clustered, arguing for niche conservatism as the main driver for this pattern. Very few studies have attempted to identify the lineages that contribute to such assembly patterns. We aimed to improve our understanding of the assembly of flooded forest tree communities in Northern South America by asking the following questions: are seasonally flooded forests phylogenetically clustered? If so, which angiosperm lineages are over-represented in seasonally flooded forests? To assess our hypotheses, we investigated seasonally flooded and terra firme forests from the Magdalena, Orinoco and Amazon Basins, in Colombia. Our results show that, regardless of the river basin in which they are located, seasonally flooded forests of Northern South America tend to be phylogenetically clustered, which means that the more abundant taxa in these forests are more closely related to each other than expected by chance. Based on our alpha and beta phylodiversity analyses we interpret that eudicots are more likely to adapt to extreme environments such as seasonally flooded forests, which indicates the importance of environmental filtering in the assembly of the Neotropical flora.


Assuntos
Florestas , Filogenia , Análise por Conglomerados , Inundações , América do Sul
15.
Primates ; 57(2): 241-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26910234

RESUMO

Woolly monkeys are endangered New World Primates whose natural ecological requirements are known from few sites. This study aimed to investigate the diet of woolly monkeys (Lagothrix lagothricha, Atelidae) to examine how availability determines fruit choice at local and regional scales. We followed two groups of woolly monkeys in the Mosiro Itajura-Caparú biological station in the Colombian Amazon for 16 months, and then compared our observations with previous studies for this and other sites in the Amazon and eastern Andes. We found a high prevalence of fruits in the diet of woolly monkeys in Caparú, which was supplemented with arthropods and leaves. This pattern was observed in all age/sex classes, although juveniles ate more arthropods, and females with dependent young ate more leaves than other classes. We suggest these differences might be due to intragroup competition and particular nutritional requirements in each age/sex class. When comparing the fruit diet composition in Caparú (>190 species) with four other places, we found that Moraceae, Fabaceae, and Sapotaceae were consistently important tree families in the Amazonian sites, and that forest richness is a good predictor of the diet richness. Overall, the results support the hypothesis that woolly monkeys are opportunistic frugivores that are able to adapt their diet to the forest supply and to the temporal variation in resource availability.


Assuntos
Atelinae/fisiologia , Dieta , Meio Ambiente , Comportamento Alimentar , Frutas/classificação , Animais , Colômbia , Feminino , Masculino
16.
Am J Primatol ; 78(4): 391-401, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26684405

RESUMO

Undisturbed primate communities in the Neotropics are bottom-up structured as their biomass and species richness can be predicted from fruit production. However, the effects of fruit scarcity and the availability of forest types have not been fully analyzed, and seasonality is expected to differently affect small and large monkeys. The first aim of this study was to examine the effect of contrasting forest types within a location on the temporal variation in fruit production. The second was to assess the relative roles of disturbance, climate, patterns of fruit and leaf production, and plant composition on determining Neotropical primate communities. I compiled population density data for diurnal primate species from 154 sites to calculate species richness and assemblage biomass. Fruit abundance in the study sites was estimated from fruit trap data and phenology transects, and fruit variability was calculated as the monthly coefficient of variation (CV) and the length of the fruit scarcity period (LFSP). The results indicate that fruit production in floodplain forests is generally more variable than in terra firme forests, and this variation decreases in habitats with mixed forest types. Endozoochorous fruit production (based on fruit traps) and litter productivity were good predictors of the biomass of Neotropical primates (R2 = 0.83 and R2 = 0.59, respectively), but neither CV nor LFSP were good predictors. The biomass of large primates was independent of rainfall variation, but the biomass of small and medium sized monkeys was negatively correlated with temporal rainfall variability. Varzea forests tended to show higher biomass than those from terra firme and igapó. These results suggest that the production of fleshy fruits is the best predictor of the structure of primate assemblages in the Neotropics, but the effect of leaf quality and productivity remains to be investigated. Am. J. Primatol. 78:391-401, 2016. © 2015 Wiley Periodicals, Inc.

17.
PLoS One ; 10(10): e0140751, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26492037

RESUMO

Frugivory is a widespread mutualistic interaction in which frugivores obtain nutritional resources while favoring plant recruitment through their seed dispersal services. Nonetheless, how these complex interactions are organized in diverse communities, such as tropical forests, is not fully understood. In this study we evaluated the existence of plant-frugivore sub-assemblages and their phylogenetic organization in an undisturbed western Amazonian forest in Colombia. We also explored for potential keystone plants, based on network analyses and an estimate of the amount of fruit going from plants to frugivores. We carried out diurnal observations on 73 canopy plant species during a period of two years. During focal tree sampling, we recorded frugivore identity, the duration of each individual visit, and feeding rates. We did not find support for the existence of sub assemblages, such as specialized vs. generalized dispersal systems. Visitation rates on the vast majority of canopy species were associated with the relative abundance of frugivores, in which ateline monkeys (i.e. Lagothrix and Ateles) played the most important roles. All fruiting plants were visited by a variety of frugivores and the phylogenetic assemblage was random in more than 67% of the cases. In cases of aggregation, the plant species were consumed by only primates or only birds, and filters were associated with fruit protection and likely chemical content. Plants suggested as keystone species based on the amount of pulp going from plants to frugivores differ from those suggested based on network approaches. Our results suggest that in tropical forests most tree-frugivore interactions are generalized, and abundance should be taken into account when assessing the most important plants for frugivores.


Assuntos
Florestas , Dispersão de Sementes , Animais , Comportamento Alimentar , Herbivoria/fisiologia , Filogenia , Plantas/parasitologia
18.
Proc Natl Acad Sci U S A ; 112(34): 10744-9, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26261350

RESUMO

Climate change is expected to cause shifts in the composition of tropical montane forests towards increased relative abundances of species whose ranges were previously centered at lower, hotter elevations. To investigate this process of "thermophilization," we analyzed patterns of compositional change over the last decade using recensus data from a network of 16 adult and juvenile tree plots in the tropical forests of northern Andes Mountains and adjacent lowlands in northwestern Colombia. Analyses show evidence that tree species composition is strongly linked to temperature and that composition is changing directionally through time, potentially in response to climate change and increasing temperatures. Mean rates of thermophilization [thermal migration rate (TMR), °C ⋅ y(-1)] across all censuses were 0.011 °C ⋅ y(-1) (95% confidence interval = 0.002-0.022 °C ⋅ y(-1)) for adult trees and 0.027 °C ⋅ y(-1) (95% confidence interval = 0.009-0.050 °C ⋅ y(-1)) for juvenile trees. The fact that thermophilization is occurring in both the adult and juvenile trees and at rates consistent with concurrent warming supports the hypothesis that the observed compositional changes are part of a long-term process, such as global warming, and are not a response to any single episodic event. The observed changes in composition were driven primarily by patterns of tree mortality, indicating that the changes in composition are mostly via range retractions, rather than range shifts or expansions. These results all indicate that tropical forests are being strongly affected by climate change and suggest that many species will be at elevated risk for extinction as warming continues.


Assuntos
Florestas , Aquecimento Global , Árvores/fisiologia , Clima Tropical , Altitude , Biodiversidade , Colômbia , Extinção Biológica , Temperatura Alta , Especificidade da Espécie , Inquéritos e Questionários , Árvores/crescimento & desenvolvimento
19.
Mol Phylogenet Evol ; 82 Pt B: 511-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24905154

RESUMO

The taxonomic history of the genus Lagothrix is complex, with molecular and morphological assessments giving conflicting results for the separation between its taxa. Phylogeographic studies of the most widely distributed species, Lagothrix lagotricha, have only been attempted recently and are limited to few individuals per collection site, many of which were captive making their geographical origin dubious. There is debate regarding the possibility of raising subspecies of Lagothrix lagotricha to the species level, therefore the geographical origin of samples is particularly relevant. In the present work we revisit the intraspecific phylogeography of L. lagotricha from northwestern South America, including the subspecies L. l. poeppiggi, L. l. lagotricha and L. l. lugens (sensu Fooden, 1963), using DNA sequence data from hypervariable region I of the mitochondrial control region (D-loop HVI). Our results suggest a complex picture in which there are well delimited evolutionary units that, nonetheless, do not correlate well with the morphological variation used to support the current delimitation of taxa. Additionally, we corroborate previous results showing a lack of reciprocal monophyly between the putative subspecies of Lagothrix lagotricha, and we propose that this may be due to ancestral polymorphism that has been maintained following the recent spread of woolly monkeys throughout the western Amazonian lowlands and into the inter-Andean region of Colombia.


Assuntos
Atelinae/classificação , Evolução Biológica , Filogenia , Animais , Atelinae/genética , Colômbia , DNA Mitocondrial/genética , Haplótipos , Filogeografia , Análise de Sequência de DNA , América do Sul
20.
PLoS One ; 7(9): e45199, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23028844

RESUMO

The Amazon harbours one of the richest ecosystems on Earth. Such diversity is likely to be promoted by plant specialization, associated with the occurrence of a mosaic of landscape units. Here, we integrate ecological and phylogenetic data at different spatial scales to assess the importance of habitat specialization in driving compositional and phylogenetic variation across the Amazonian forest. To do so, we evaluated patterns of floristic dissimilarity and phylogenetic turnover, habitat association and phylogenetic structure in three different landscape units occurring in terra firme (Hilly and Terrace) and flooded forests (Igapó). We established two 1-ha tree plots in each of these landscape units at the Caparú Biological Station, SW Colombia, and measured edaphic, topographic and light variables. At large spatial scales, terra firme forests exhibited higher levels of species diversity and phylodiversity than flooded forests. These two types of forests showed conspicuous differences in species and phylogenetic composition, suggesting that environmental sorting due to flood is important, and can go beyond the species level. At a local level, landscape units showed floristic divergence, driven both by geographical distance and by edaphic specialization. In terms of phylogenetic structure, Igapó forests showed phylogenetic clustering, whereas Hilly and Terrace forests showed phylogenetic evenness. Within plots, however, local communities did not show any particular trend. Overall, our findings suggest that flooded forests, characterized by stressful environments, impose limits to species occurrence, whereas terra firme forests, more environmentally heterogeneous, are likely to provide a wider range of ecological conditions and therefore to bear higher diversity. Thus, Amazonia should be considered as a mosaic of landscape units, where the strength of habitat association depends upon their environmental properties.


Assuntos
Filogenia , Fenômenos Fisiológicos Vegetais , Plantas/classificação , Biodiversidade , Clima , Colômbia , Inundações , Filogeografia , Árvores
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