Barteria fistulosa and B. dewevrei, central African rain-forest trees, provide nesting cavities for Tetraponera aethiops and T. latifrons ants, respectively, which protect them against herbivores. To compare protection efficiency between these two symbioses, for 20 plants of each species in two sites in Gabon we measured the time elapsed before ants reached a focal leaf, for host leaves that were undisturbed, damaged (cut with scissors) or subjected to slight vibration (mimicking such damage), and for damaged leaves of the non-host Barteria species. Tetraponera aethiops displayed stronger protective behaviour than did T. latifrons. Time to reach a damaged host leaf (4.5 ± 2.6 min, mean ± SD) did not differ significantly from time to reach a leaf subjected to slight vibration (5.2 ± 3.0 min) for T. aethiops, but response to a leaf subjected to slight vibration (9.5 ± 1.9 min) was significantly slower than that to a damaged leaf (7.8 ± 1.9 min) for T. latifrons. The faster response of T. aethiops to slight vibration may have masked a response of this species to chemical signalling. Both ants reached damaged host leaves faster than damaged leaves of the non-host Barteria sp., indicating host plant specificity in ant responses.

Cyclopes didactylus, the smallest of all anteaters, inhabits Amazonian and Atlantic forests with an apparently disjunct distribution. Yet, phylogeography reveals historical connections through the forests of the Northeast Region of Brazil. Its populations in this region are classified by the Red List of Threatened Species as Data Deficient and with a trend towards decline. However, Northeast Brazil has a large sampling gap, and the potential distribution of this species has yet to be evaluated. We investigated the potential distribution of C. didactylus to evaluate the hypothesis of a disjunct distribution between Amazonian and Atlantic forests and estimate the amount of protected area in its predicted distribution. We generated a Maxent distribution model using occurrence records, according to the new taxonomic revision of Cyclopes, and selected current bioclimatic variables to evaluate the continuity of the predicted distribution of the species in Northeast Brazil. We also performed past projections to assess historical connections and overlapped maps of protected areas onto their current distribution. Although its distribution is probably disjunct, at least one as-yet-unknown population may be present in the forests of Northeast Brazil, an area poorly protected. The results are useful for targeting field efforts in this under-sampled region.

Litter decomposition plays an important role in the carbon cycle and is affected by many factors in forest ecosystems. This study aimed to quantify the rhizosphere priming effect on litter decomposition in subtropical forest southwestern China. A litter decomposition experiment including control and trenching treatments was conducted using the litter bag method, and the litter decomposition rate was calculated by litter dry mass loss. Trenching did not change soil temperature, but increased the soil water content by 14.5%. In this study, the interaction of soil temperature and soil water content controlled the litter decomposition rate, and explained 87.4 and 85.5% of the variation in litter decomposition in the control and trenching treatments, respectively. Considering changes in soil environmental factors due to trenching, the litter decomposition rates were corrected by regression models. After correction, the litter decomposition rates of the control and trenching treatments were 32.47 ± 3.15 and 25.71 ± 2.72% year–1, respectively, in the 2-year period. Rhizosphere activity significantly primed litter decomposition by 26.3%. Our study suggested a priming effect of rhizosphere activity on litter decomposition in the subtropical forest. Combining previous interaction effect results, we estimated the contributions of total soil organic matter (SOM) decomposition, total litter decomposition, and root respiration to soil respiration in the subtropical forest, and our new method of estimating the components of soil respiration provided basic theory for SOM decomposition research.

Compounds of the 20 elements needed by living organisms are relatively soluble in water and therefore vulnerable to being leached and lost from terrestrial ecosystems during mineralization. Intact systems have thus acquired retention mechanisms that sequester nutrients and minimize losses. Such mechanisms should be particularly important where rainfall is very high but direct evidence of retention mechanisms in tropical forests is scarce (Snaddon et al. 2012, Turner et al. 2007).

In South-East Asian tropical plants, the excess production of reproductive organs is believed to be controlled by resource booms. However, the continuously flowering shrub Dillenia suffruticosa (Dilleniaceae) is often infested by fruit predators and occasionally produces fruits where mature seeds are absent. These reproductive features may support an alternative hypothesis for excess production of reproductive organs: the reproductive assurance hypothesis. We marked 1190 reproductive organs in 180 inflorescences of 41 plant individuals and examined the relationships among the reproductive organ features and the effects of both climate and predators. During the flower budding stage, the fate of reproductive organs was primary climate-induced. The percentage of flower/fruit abscission increased as the cumulative temperature and photosynthetically active radiation (PAR) decreased and the cumulative precipitation increased, supporting the resource boom hypothesis. Insect predation was the most common fate of immature fruits. As PAR increased, the prevalence of insect predation and production of mature seed increased. At a reduced PAR, the production of fruits with many immature seeds could serve as compensatory reproductive organs for insect predators, consistent with the reproductive assurance hypothesis. The excess production of reproductive organs might be a result of adaptation to climate fluctuations in the South-East Asian tropics.

Although two studies (Loubry 1994, Sabatier 1985) have been conducted on the phenology of primary forest tree species in French Guiana, there exists little synthetic information on the phenology of a forest dominated by pioneer species. Charles-Dominique (1986) conducted zoological observations at ARBOCEL between 1981 and 1985, where he indicated the fruiting periods of certain species. However, stands of early pioneer plants such as Solanum spp. and Cecropia obtusa Trécul 9Cecropiaceae) have reduced in number or have completely disappeared from the study area since then (Larpin 1989, Toriola et al. 1998).

The mechanisms underlying occupancy patterns of species in modified tropical landscapes are poorly understood. The presence of adults in a modified habitat may not necessarily indicate the quality of the habitat for sub-adult stages. These issues were addressed by examining patterns in breeding-site use by adult frogs and tadpole performance across a pasture-forest gradient in the Osa Peninsula, Costa Rica. The use of artificial pools by adult frogs for breeding activity was quantified along three transects, with a pool located at the edge (0 m) and 10, 30 and 50 m into forest and pasture. Next, survival, size at metamorphosis and time to metamorphosis were quantified for tadpoles of Engyptomops pustulosus and Dendrobates auratus in artificial pools at the edge, pasture and forest. Adult frogs used breeding pools non-randomly; two species used pools only in pasture, whereas three species used pools only in forest. In addition, Smilisca phaeota used pools in pasture and at the edge while E. pustulosus used pools across the pasture-forest gradient. The habitat where adults used breeding pools generally also yielded high performance of their tadpoles, with some exceptions. Tadpole survival to metamorphosis was low in pastures (<5%) and higher in edge and forest (>18%) for D. auratus; in contrast, survival of E. pustulosus was over 80% in each habitat. Metamorphs of D. auratus were largest in edges but larval period did not differ among habitats. Metamorphs of E. pustulosus were 18% larger and larval period was 27% shorter in pastures compared with forest. These results suggest that modified habitats represent an ecological jackpot for some species, such that offspring performance is enhanced compared with that in forest habitat. Populations of other species may be restricted to forest habitat because of intolerable abiotic conditions in modified habitats. The results of this study indicate that adult breeding site use and tadpole performance contribute to mechanisms that underlie patterns of species occupancy in modified tropical landscapes.

Interspecific kleptoparasitism (the stealing of already-procured items from other species) has received little attention in tropical reptiles. We report here the second case of kleptoparasitism in tropical lizards, and the first known case of pollen theft by a vertebrate species. Phelsuma inexpectata, a gekkonid lizard endemic to Réunion, was observed robbing pollen pellets from honeybees (Apis mellifera) foraging on Latania lontaroides flowers. Video-records were used to obtain reliable information on gecko-honeybee interactions occurring on L. lontaroides inflorescences. During the 19 observation periods (total duration 140 min) a total of 78 attempts were recorded, at least 40% were successful. Both males and females displayed kleptoparasitic behaviour. A high level of gecko kleptoparasitism occurred, with an average one-robbery attempt every 2 min. Behaviour of both the kleptoparasitic P. inexpectata and its host A. mellifera are described.

Different methods to measure species behaviour and space use may produce diverging results, and provide advantages and shortcomings. Data from spot-mapping of animals might be affected from restricted detectability of individuals in dense vegetation, while radio-tracking provides a less biased (or even unbiased) measure of space use. Here we compare results from spot-mapping and telemetry of four family groups (i.e. five individuals belonging to these four family groups), respectively of the Kenyan endemic cooperative-breeding bird Hinde's babbler, Turdoides hindei. Data from spot-mapping showed that the space use of T. hindei is mostly restricted to riparian vegetation. Home-range sizes calculated from telemetry were five times larger if compared with data obtained from spot-mapping. Telemetry data showed that T. hindei also moves across agricultural land, and mean and maximum displacements are larger if compared with data obtained from spot-mapping. Several reasons might lead to these differences: (1) Telemetry data also consider rare long-distance excursions, while (2) observers of spot-mapping might fail to observe long-distance movements and thus underestimate home-range sizes as well as displacement distances; (3) results from telemetry might become blurred from measurement error during the triangulation of fixes. Our study confirms that both methods provide advantages, but also shortcomings, which need to be considered when selecting a method to elaborate a research question.

Palms are important components of tropical forest plant communities, due both to their abundance (Henderson et al. 2000) and to the network of interactions with their pollinators and dispersers (Henderson 2002, Zona & Henderson 1989). Forest fragmentation alters the biotic and abiotic conditions of habitats (Ewers & Didham 2006, Fahrig 2003) and it has been observed that Attalea palms increase their densities in disturbed sites (Aguiar & Tabarelli 2009, Andreazzi et al. 2012, Lorenzi et al. 2004). Increased light availability (Salm 2005, Souza & Martins 2004), changes in seed dispersal and predation patterns (Andreazzi et al. 2012, Pimentel & Tabarelli 2004, Wright et al. 2000), and ability to recover after disturbance (Souza & Martins 2004) are among the main mechanisms that have been proposed to explain enhanced palm densities. However, how altered conditions following disturbances influence the dynamics of flower and fruit production is still little understood.

Quantifying tree biomass is an important research and management goal across many disciplines. For species that exhibit predictable relationships between structural metrics (e.g. diameter, height, crown breadth) and total weight, allometric calculations produce accurate estimates of above-ground biomass. However, such methods may be insufficient where inter-individual variation is large relative to individual biomass and is itself of interest (for example, variation due to herbivory). In an East African savanna bushland, we analysed photographs of small (<5 m) trees from perpendicular angles and fixed distances to estimate above-ground biomass. Pixel area of trees in photos and diameter were more strongly related to measured, above-ground biomass of destructively sampled trees than biomass estimated using a published allometric relation based on diameter alone (R2 = 0.86 versus R2 = 0.68). When tested on trees in herbivore-exclusion plots versus unfenced (open) plots, our predictive equation based on photos confirmed higher above-ground biomass in the exclusion plots than in unfenced (open) plots (P < 0.001), in contrast to no significant difference based on the allometric equation (P = 0.43). As such, our new technique based on photographs offers an accurate and cost-effective complement to existing methods for tree biomass estimation at small scales with potential application across a wide variety of settings.

Several species of neotropical felines are morphologically and ecologically similar, and are sympatric along large areas of their distribution. This requires mechanisms to allow their coexistence, such as temporal segregation of their activities. The aim of this study was to evaluate the relation between activity patterns of felines and their prey using camera trapping data and their seasonal variation in two tropical environments in south-western Mexico. Excepting Puma concolor, activity patterns for each feline species did not differ significantly between seasons nor between vegetation types. Activity patterns did not differ significantly between species of similar size: mid-sized species had high activity pattern overlaps in the medium forest while large-sized species overlapped to a lesser extent in the cloud forest. Leopardus wiedii differed from large-sized predators in its activity patterns. We recorded a relatively high temporal overlap between felines and their main prey species, particularly in the periods of maximum activity. We found no evidence of temporal segregation between the felines of the Sierra Norte region of Oaxaca and we suggest their coexistence is mediated by the selection of prey with different activity patterns.

Biological invasions are a threat to protected areas globally; however, the relative lack of studies quantifying the ecological impacts impairs informed decision-making. We selected three annual alien plants, widespread in the riparian habitats of the Kruger National Park, South Africa: Datura innoxia, Parthenium hysterophorus, and Xanthium strumarium, to examine their potential impacts on riparian plant communities. We identified 12–13 populations for each and placed a pair of invaded and uninvaded plots in each population. Species richness, Shannon diversity, and Pielou evenness were compared between the invaded and uninvaded plots using LMM models, and species composition was compared using ordination. The invaded vegetation showed lower species richness compared to the uninvaded, with the strongest effect observed for P. hysterophorus. The invaded plots also showed lower Shannon diversity and Pielou evenness due to the presence of alien dominants. For all three invaders, the invasion resulted in changes in the composition of native vegetation. Some native plants were more frequent and abundant in the invaded vegetation, possibly due to the habitats created in sandy river beds. The native species richness decreased with increasing invader cover, but the species richness of aliens accompanying the invasive dominants was not negatively affected by their cover. Our results confirmed the negative impact of invasive aliens on native plant diversity, with the most pronounced effect by Parthenium hysterophorus invasions.

One of the biggest issues in plant ecology is determining the interaction outcome between seeds and scatter-hoarding rodents because the latter has a dual role as dispersers and predators of seeds. Density-dependence contexts involving resource abundance largely influence the outcome of this interaction. Here, we investigated how the variation in the density of a large-seeded tropical tree (Joannesia princeps Vell) affects its probability of seed removal, consumption, dispersal, and burial by a neotropical rodent (Dasyprocta azarae Lichtenstein). We tested whether the elevated resource availability in high tree density areas would cause scatter hoarder’s satiation by decreasing seed removal and consumption (predator satiation hypothesis) or increasing seed dispersal and burial (predator dispersal hypothesis). We tracked the fate of 461 seeds in 14 plots with distinct J. princeps abundances inside a large Atlantic Forest fragment. We used spool-and-line tracking and camera trappings to determine seed fate and identify interacting animals. Agouti was the only species removing J. princeps seeds. Tree density benefitted J. princeps by increasing seed dispersal through buried seed but not affecting seed removal and consumption. This result shows how density-dependent contexts, such as tree density, may alter seed fate in seed–rodent interactions supporting future studies aiming to reestablishing seed dispersal functions in Atlantic Forest fragments.

Soil type may drive vegetation structure. In turn, the richness, identity and diversity of arthropod herbivores may be related to plant diversity through specific host plant relationships in a location. We test the hypothesis that the soil type (calcicolous vs alluvial soils) will drive the assemblage structure of a dominant group of arthropod herbivores: the moths. We used sampling sites in rain-forest fragments in south-western China around the Xishuangbanna Tropical Botanical Gardens (21°41′N, 101°25′E) to test this hypothesis. We used Pennsylvania style light traps to take point samples of macromoths and pyraloids from four sampling sites in forest remnants on a limestone geological base and four from alluvial-based forest. A total of 3165 moths (1739 from limestone-based and 1255 from alluvium-based forests) was collected representing 1255 species. The limestone-based sites showed statistically similar levels of species richness and other alpha diversity indices to the four alluvium-based site. Nevertheless the sites were clearly significantly different in terms of species composition. Analysis of contrasting similarity (‘beta’ diversity) indices suggested that there was ‘leakage’ between the two classes of sites when ‘rare’ species were emphasized in the calculations. We used an indicator value procedure to select species that most characterized this separation. We expect that these differences reflect associated changes in plant assemblage structure acting through the herbivorous habits of larval moths. Accordingly, in any assessment of landscape level diversity the nature of the substrate and its associated vegetation is clearly of great importance. This observation also has consequences for the design of conservation programmes.

During the last two decades, the world has witnessed the emergence and re-emergence of arthropod-borne viruses, better known as arboviruses. The close contact between sylvatic, rural and peri-urban vector species and humans has been mainly determined by the environment-modifying human activity. The resulting interactions have led to multiple dead-end host infections and have allowed sylvatic arboviruses to eventually adapt to new vectors and hosts, contributing to the establishment of urban transmission cycles of some viruses with enormous epidemiologic impact. The metagenomic next-generation sequencing (NGS) approach has allowed obtaining unbiased sequence information of millions of DNA and RNA molecules from clinical and environmental samples. Robust bioinformatics tools have enabled the assembly of individual sequence reads into contigs and scaffolds partially or completely representing the genomes of the microorganisms and viruses being present in biological samples of clinical relevance. In this review, we describe the different ecological scenarios for the emergence of viral diseases, the virus adaptation process required for the establishment of a new transmission cycle and the usefulness of NGS and computational methods for the discovery and routine genomic surveillance of mosquito-borne viruses in their ecosystems.

Theory predicts that honest signalling strategies will not always be evolutionarily stable in interspecific communication, yet to demonstrate such a transition of signalling modality between honesty and dishonesty in the wild would be difficult. An endocarp dimorphism has been found in Scaevola taccada fruits: a morph with a cork substrate that facilitates ocean current seed dispersal and a morph without the cork. Both types of fruit are covered with sugar-containing flesh, and are similar in size and colour to one another (at least from a human perspective). The apparent lack of external differences between morphotypes could potentially degrade mutualistic relations between the plant and seed-dispersing birds because the presence of a cork could lower the fruit's nutritional value. Thus, unless seed dispersers can discriminate between the different types of fruit, this system may provide an example of a transition between honest and dishonest signalling. We examined S. taccada fruit and leaf colours from an avian visual perspective. Even though the fruits and leaves were different in colour from one another to birds, there was no perceivable difference in the colours between fruit morphotypes. Therefore, fruit colour is not an honest indicator of reward to seed dispersers. Further, we propose an adoption of a statistical method in avian visual modelling studies that avoids the common statistical errors, such as violation of the congruence principle.

A suite of woody plants inhabiting the seasonally dry tropics flower while leafless during the dry season, raising intriguing questions about the role of moisture limitation in shaping their phenology. Brachychiton megaphyllus is one such species, a shrub of open forests and savannas in northern Australia. We documented leaf and reproductive phenology of 14 shrubs, and irrigated a further 15, to determine if soil moisture affected leafiness and reproductive activity. Brachychiton megaphyllus showed first flower buds shortly after the cessation of wet-season rains, and budded and flowered throughout the dry season. In some plants, leaf flush occurred prior to the first rains. Rates of fruit set and maturity were very low. Irrigation did not significantly influence leaf shoot or subsequent canopy development. Contrary to expectation, irrigation decreased the production of buds and flowers though it had no impact on the production of fruit, a response for which we suggest a number of hypotheses. Phenological responses to irrigation may have been limited because B. megaphyllus responds primarily to cues other than soil moisture and is buffered against seasonal drought by a large tap root. This suggests mechanisms by which flowering while leafless may occur in a range of species.

Actinobacteria that live mutualistically with leaf-cutter ants secrete antibiotics that may induce antibiotic resistance in nearby soil bacteria. We tested for the first time whether soil bacteria near and inside Atta cephalotes nests in Costa Rica show higher levels of antibiotic resistance than bacteria collected farther away. We collected soil samples 0 m to 50 m away from ant nests and grew bacteria from them on agar with paper discs treated with antibiotics of common veterinary use. As a proxy for antibiotic resistance, we measured the distance from the edge of each disc to the closest bacterial colonies. In general, resistance to oxytetracycline increased with proximity to leaf-cutter ant nests. Antibiotic resistance to oxytetracycline was also higher in samples collected inside the nest than in samples from the nest mound; not all antibiotics demonstrated the same trend. A preliminary exploratory morphological analysis suggests bacterial communities between 0 m and 50 m from ant nests were similar in diversity and abundance, indicating the pattern of antibiotic resistance described above may not be caused by differences in community composition. We conclude that actinobacteria living mutualistically with A. cephalotes drive natural antibiotic resistance to tetracycline in proximal bacterial communities.