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Aim Temporal dynamics of biodiversity along tropical elevational gradients are unknown. We studied seasonal changes of Lepidoptera biodiversity along the only complete forest elevational gradient in the Afrotropics. We focused on shifts of species richness patterns, seasonal turnover of communities, and seasonal shifts of species’ elevational ranges, the latter often serving as an indicator of the global change effects on mountain ecosystems. Location Mount Cameroon, Cameroon. Taxon Butterflies and moths (Lepidoptera) Methods We quantitatively sampled nine groups of Lepidoptera by bait-trapping (16,800 trap-days) and light-catching (126 nights) at seven elevations evenly distributed along the elevational gradient from sea level (30 m asl) to timberline (2,200 m asl). Sampling was repeated in three seasons. Result Altogether, 42,936 specimens of 1,099 species were recorded. A mid-elevation peak of species richness was detected for all groups but Eupterotidae. This peak shifted seasonally for five groups, most of them ascending during the dry season. Seasonal shifts of species’ elevational ranges were mostly responsible for these diversity pattern shifts along elevation: we found general upward shifts in fruit-feeding butterflies, fruit-feeding moths and Lymantriinae from beginning to end of the dry season. Contrarily, Arctiinae shifted upwards during the wet season. The average seasonal shifts of elevational ranges often exceeded 100 metres and were even several times higher for numerous species. Main conclusion We report seasonal uphill and downhill shifts of several lepidopteran groups. The reported shifts can be driven by both delay in weather seasonality and shifts in resource availability, causing phenological delay of adult hatching and/or adult migrations. Such shifts may lead to misinterpretations of diversity patterns along elevation if seasonality is ignored. More importantly, considering the surprising extent of seasonal elevational shifts of species, we encourage taking account of such natural temporal dynamics while investigating the global climate change impact on communities of Lepidoptera in tropical mountains. The dataset was collected by two methodologies: 1/ bait-trapping and 2/ manual catching of target group at light. See Maicher et al. (2019) for details.

Here, we explore the mating pattern and genetic structure of a tropical tree species, Cariniana estrellensis, in a small population in which progeny arrays (n=399), all adults (n=28) and all seedlings (n=39) were genotyped at nine highly informative microsatellite loci. From progeny arrays we were able to identify the source tree for at least 78% of pollination events. The gene immigration rates, mainly attributable to pollen, were high, varying from 23.5 to 53%. Although gene dispersal over long distance was observed, the effective gene dispersal distances within the small population were relatively short, with mean pollination distances varying from 69.9 to 146.9 m, and seed dispersal distances occurring up to a mean of 119.6 m. Mating system analyses showed that C. estrellensis is an allogamous species (tm=0.999), with both biparental inbreeding (tm−ts=−0.016) and selfing rates (s=0.001) that are not significantly different from zero. Even though the population is small, the presence of private alleles in both seedlings and progeny arrays and the elevated rates of gene immigration indicate that the C. estrellensis population is not genetically isolated. However, genetic diversity expressed by allelic richness was significantly lower in postfragmentation life stages. Although there was a loss of genetic diversity, indicating susceptibility of C. estrellensis to habitat fragmentation, no evidence of inbreeding or spatial genetic structure was observed across generations. Overall, C. estrellensis showed some resilience to negative genetic effects of habitat fragmentation, but conservation strategies are needed to preserve the remaining genetic diversity of this population. SSR genotypes for adults, seedlings and progeny arrays of Cariniana estrellensisGenotypes of Cariniana estrellensis (Lecythidaceae) individuals (adults, seedlings and progeny arrays) based on nine microsatellite loci.SSR_genotypes.xlsx

1. Woody encroachment into grassy biomes is a global phenomenon, often resulting in a nearly complete turnover of species, with savanna specialists being replaced by forest-adapted species. Understanding the mechanisms involved in this change is important for devising strategies for managing savannas. 2. We examined how isolated trees favor woody encroachment and species turnover by overcoming dispersal limitation and environmental filtering. In a savanna released from fire in southeastern Brazil (Cerrado) we sampled woody plants establishing under 40 tree canopies and in paired treeless plots. These trees comprised eight species selected for habitat preference (savanna or forest) and dispersal syndrome (bird-dispersed or not). We recorded dimensions of each tree, dispersal syndrome and habitat preference of recruits, and quantified the physical environment within each plot, aiming at a mechanistic understanding of woody encroachment. 3. We found clear evidence that isolated trees cause nucleation and drive changes in functional composition of savanna. Effectiveness as nucleator differed among species, but was unrelated to their functional guilds (habitat preference or dispersal syndrome). Density of saplings in nuclei was partially explained by soil moisture (+), daily temperature amplitude (-), and sum of bases (-). 4. Our results indicate that isolated trees act first as perches, strongly favoring bird-dispersed species. They then act as nurse trees, considerably changing the environment in favor of forest-adapted recruits. In the long term, as the nuclei expand and merge, savanna specialists tend to disappear and the savanna turns into a low-diversity forest. 5. Synthesis and applications: Fire suppression has allowed the nucleation process and consequently the woody encroachment and fast replacement of savanna specialists by forest species in the Cerrado. By elucidating the mechanisms behind woody encroachment, we recommend using prescribed fires to burn forest seedlings and to reduce tree canopy size wherever the management goal is to maintain the typical savanna structure and composition. Please see Methods in the article published in the Journal of Applied Ecology.

Seed dispersal is a key process driving the structure, composition, and regeneration of tropical forests. Larger frugivores play a crucial role in community structuring by dispersing large seeds not dispersed by smaller frugivores. We assessed the hypothesis that brown howler monkeys (Alouatta guariba clamitans) provide seed dispersal services for a wide assemblage of plant species in both small and large Atlantic forest fragments. Although fruit availability often decreases in small fragments compared with large ones, we predicted that brown howlers are efficient seed dispersers in quantitative and qualitative terms in both forest types given their high dietary flexibility. After a 36-month study period and 2,962 sampling hours, we found that howlers swallowed and defecated intact the vast majority of seeds (96%-100%) they handled in all study sites. Overall, they defecated ca. 315,600 seeds belonging to 98 species distributed in eight growth forms. We estimated that each individual howler dispersed an average of 143 (SD = 49) seeds >2 mm per day or 52,052 (SD = 17,782) seeds per year. They dispersed seeds of 58% to 93% of the local assemblages of fleshy-fruit trees. In most cases, the richness and abundance of seed species dispersed was similar between small and large fragments. However, groups inhabiting small fragments tended to disperse a higher diversity of seeds from rarely consumed fruits than those living in large fragments. We conclude that brown howlers are legitimate seed dispersers for most fleshy-fruit species of the angiosperm assemblages of their habitats, and that they might favor the regeneration of Atlantic forest fragments with the plentiful amount of intact seeds that they disperse each year. Dataset_seeds_dispersedHere we provided data on seed dispersal by six wild groups of brown howler monkeys (Alouatta guariba clamitans). This research was conducted during a 36-month period in three small (<10 ha: S1, S2, and S3) and three large (>90 ha: L1,L2, and L3) Atlantic forest fragments in Rio Grande do Sul State, southern Brazil.Dataset_seed_handlingHere we provided data on seed/fruit handling by six wild groups of brown howler monkeys (Alouatta guariba clamitans). This research was conducted during a 36-month period in three small (<10 ha: S1, S2, and S3) and three large (>90 ha: L1,L2, and L3) Atlantic forest fragments in Rio Grande do Sul State, southern Brazil.

Improving species delimitation and knowledge on species complexes is crucial for many areas of study in Biology, especially conservation. Integrative taxonomy contributes to this topic by using different approaches to better delineate taxonomic boundaries. Metternichia (Solanaceae), historically a monospecific genus, has a geographic range that comprises contrasting environments. Metternichia principis was described as having two varieties: the typical variety, found in the humid forests of eastern Brazil (Atlantic Forest region), and M. principis var. macrocalyx, which presents larger calyx and inhabits mostly semi-arid areas (Caatinga region). In this study we tested the validity of such groups by integrating environmental, phenological, morphometric and palynological data; applying uni and multivariate tests; and evaluating the conservation status of each taxon. Our results support the recognition of two morphological groups within Metternichia, largely in agreement with the original circumscription of the varieties. Multivariate analyses clearly indicate different ecological niches, with each taxon inhabiting environments with distinct mean annual precipitation and temperature. Phenological data show some differences between the varieties regarding months with the highest number of flowering and fruiting records. In general, M. principis var. macrocalyx presents larger flower and pollen characters, and smaller fruit characters compared to the typical variety. Based on these findings, we elevate the variety to the status of species, as the new combination Metternichia macrocalyx. Following IUCN guidelines, both taxa are here considered endangered (EN). Morphometric data were collected through measurements of leaf, flower, fruit and seed traits from exsiccatae. Pollen data were collected through measurements of images of acetolysed pollen grains taken from light microscope. Environmental data were obtained through WorldClim database and asigned to each specimen of the morphometric dataset. Morphometric and palynological data were created in different datasets due to the significant different number of specimens encompassed. Morphometric and palynological datasets were used for univariate analyses, while all three datasets (including the environmental) were used for multivariate analyses (PCA and HCA). To perform the analyses, users must have R and RStudio installed.

This is a dataset on benthic diatom communities sampled in 90 riffles (the local communities) within nine near-pristine subtropical streams (each stream represented a metacommunity) in southeast subtropical Brazil. In addition to the dataset, we also provide the R code used to investigate whether reduced enumeration efforts (i.e., subsets of counted valves per sample) and the identification to the genus level are sufficient to recover patterns in the species composition and in beta diversity of benthic diatom metacommunities. This study was partially funded by grant nº 2013/50424-1 from the São Paulo Research Foundation (FAPESP) to TS. ASM and LMB are supported by research grants from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq n° 313954/2021-6 and 308974/2020-4, respectively). EC was supported by a student fellowship by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) – Finance Code 001.

In the Neotropical region, euphonias (Euphonia spp., Fringillidae) are the quintessential example of specialized bird frugivores, making the bulk of feeding visits to certain mistletoes (Phoradendron spp., Santalaceae) and epiphytes in the genus Rhipsalis (Cactaceae), whose fruits have high water and low sugar and protein concentrations. Surprisingly, a mechanistic explanation for such specialized, otherwise rare, relationships is lacking. Using captive birds and artificial diets, we contrasted euphonias with frugivorous tanagers in the genus Thraupis (Thraupidae), which rarely eats Rhipsalis fruits, to test the hypothesis that the digestive capacity of euphonias entails them to exploit such low-energy fruits. We expected that compensatory feeding in response to decreasing energy density would occur only in euphonias, whose higher reliance on fruits would entail a lower nitrogen requirement than the tanagers. Euphonias and tanagers were both able to compensate energy intake as sugar density decreased, and both species had the same mass-corrected energy intake at any given sugar concentration. Similarly, euphonias and tanagers did not differ in mass-corrected maintenance nitrogen requirement. Therefore, the physiological traits we investigated do not explain euphonia´s specialization on Rhipsalis fruits. The fast rates of fruit passage typical of specialized avian frugivores as euphonias that entail the processing of a large volume of fruits, and the putative better abilities of such birds to deal with secondary compounds likely present in Rhipsalis fruits are other possible mechanisms that should be considered in future studies to unveil the mechanisms underlying the intriguing specialized relationships between euphonias and certain fruits. Please, refer to the associated article.

The interaction between ecology and evolution, particularly with regard to speciation processes, remains a main topic of scientific research. Andean hummingbirds have undergone a remarkable radiation, with many species exhibiting patchy distributions and, in some cases, taxonomic controversy. An example is the Sapphire-vented Puffleg (Eriocnemis luciani; ssp. baptistae, luciani, and meridae), which some authors merge with the Coppery-naped Puffleg (E. sapphiropygia; ssp. catharina and sapphiropygia). Each group is distributed either north or south from the Huancabamba Depression, the major biogeographical barrier within the tropical Andes. We investigated whether these subspecies share some niche characteristics despite their geographical separation and determined their meaning in the context of the speciation process of trochilids in the tropical Andes. For each subspecies, we performed geographical predictions and paired tests of niche conservatism in environmental space. Geographical predictions included separate regions for subspecies catharina and sapphiropygia, while the predicted regions for subspecies luciani and baptistae greatly overlapped. The E. l. luciani model predicted a single pixel near to the potential area of E. l. meridae, known only from a unique, old record. Subspecies luciani and baptistae exhibited the greatest niche overlap among the pairs of taxa for most variables. However, our results clearly indicated niche divergence for the four members of the E. luciani-sapphiropygia complex, independent of the similarities or slight dissimilarities in their respective backgrounds, indicating that other forces in addition to variation in environmental parameters, such as natural selection or genetic drift, are driving the radiation of these hummingbirds. This finding coincides with the unusually high speciation rates reported for Andean hummingbirds. Thus, the currently accepted taxonomy within the E. luciani-sapphiropygia complex may be even more convoluted than indicated by previous studies. Hence, the results of our study are a wakeup call to include the exploration of lineage diversification in biodiversity-related efforts.

A starter data kit for Algeria