Guilherme Costa Baião

Buffalo milk stands out for its nutritional qualities and is mainly produced in Brazil in the Amazon region, particularly in the Marajó Archipelago, State of Pará. In this context, the milk microbiome is an intriguing and underexplored research topic. This study tested the hypothesis that the buffalo milk microbiome could share taxa with faeces, pasture soil and calf spittle. A possible correlation between generations was also explored. Samples of milk, faeces, spittle and pasture soil were analysed using a 16S rRNA metabarcoding approach, revealing significant phylogenetic and ecological differences among matrices. Beta‐diversity analysis showed clustering between milk samples from heifers and cows, as well as proximity between soil and buffalo samples (milk and faeces). Relative abundance analysis identified shared taxa between buffaloes and their calves, though no clustering was observed between generations. A total of 15 bacterial families were found across all matrices, with Staphylococcaceae , Planococcaceae and Enterobacteriaceae being the most prominent. The milk microbiota was similar among animals of different ages. The grouping pattern varied depending on the animal and matrix, but not on the maternal relationship. Despite compositional differences, the shared taxa reinforce the idea of interaction among the studied microbial communities.

Located in the southeast of Brazil, the Rio Santo Antônio basin, a tributary of the Rio Doce basin, has many preserved remnants of the Atlantic Forest, but is otherwise under imminent threats from several land use stressors. In this study, we used environmental DNA (eDNA) metabarcoding to assess vertebrate diversity in the headwaters of the Rio Santo Antônio basin, aiming to elucidate key ecological factors influencing its vertebrate richness. Additionally, we provide the first vertebrate species inventory for the basin. In 2023, water samples from 15 third‐ and fourth‐order streams were collected and metabarcoding assays targeting the mitochondrial 12S rRNA gene were employed to detect the vertebrate community. We identified 119 vertebrate taxonomic units distributed across two distinct communities: one on the eastern slope and another on the western slope of the basin, both influenced by large‐scale mining activities. We demonstrated that vertebrate richness was not correlated with forest cover or pH but was strongly associated with the water's oxidation–reduction potential (ORP). We interpret ORP as a reflection of local conditions, where sites with higher ORP values also exhibited greater taxonomic richness and were related to greater forest cover, lower air and water temperatures, and greater distance from mining activity. The vertebrate biodiversity and biogeographic distribution described here highlight the value of eDNA metabarcoding as a monitoring approach and support decision‐making and conservation efforts aimed at preserving the remaining Atlantic Forest in the headwaters of the Rio Santo Antônio basin.

Given the challenges posed by the 2019 coronavirus disease (COVID-19), understanding the role of the microbiota is crucial. The analysis of this microbial community in the body not only expands our understanding of health, but also provides insights into the interaction between viruses, microbiota, and the human host. In this study, we aimed to identify possible variations in bacterial diversity caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The study involved 45 volunteers, divided into the Positive Group (PG) consisting of 14 patients and the Negative Group (NG) consisting of 31 individuals. Both groups were stratified by biological sex to ensure sample homogeneity. Samples were collected using nasopharyngeal and oropharyngeal swabs, and total DNA was extracted and stored. The V4 region of the 16S rRNA gene was sequenced, and bioinformatics tools were used to assess the composition and diversity of the respiratory microbiota. In our results, the most abundant bacterial phyla were: Firmicutes, Bacteroidetes, and Proteobacteria. There was a notable reduction in the frequency of Firmicutes in the PG, suggesting a potential compromise in the immune response to viral infection. Beta diversity analysis did not reveal significant variations between the communities of the groups. Additionally, the analysis indicated subtle changes in some taxa, such as an increase in the abundance of Neisseriaceae in patients affected by COVID-19. These findings contribute to a deeper understanding of the complex interaction between the virus, the microbiota, and the host during infection with SARS-CoV-2, highlighting the importance of the respiratory microbiota in the context of COVID-19.

Palm oil derived from the fruits of Elaeis guineensis Jacq. has global economic importance and is largely produced in tropical regions. The palm oil production process leads to a highly polluting waste called palm oil mill effluent (POME). A strategy commonly used by producers to overcome environmental issues and to improve soil fertility is the reuse of POME as a fertilizer due to the chemical and biological characteristics of the effluent. In this research, three groups were analyzed: soil without POME application (control group) and soil samples after 4 and 9 days of POME application. An environmental DNA metabarcoding approach was used. eDNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced in the Illumina MiSeq platform. The abundance of Proteobacteria (48.1%) and Firmicutes (9.0%) was higher in fertilized soil, while Bacteroidetes (20.3%) and Verrucomicrobia (7.8%) were more abundant in control soil. Additionally, the effluent seemed to modify soil characteristics favoring taxa responsible for the mineralization of organic compounds and nitrogen fixation such as species of Gammaproteobacteria class. Our study highlights the influence of POME on soil biological components and contributes to the sustainable production of palm oil in the Amazon.

Island biodiversity has long fascinated biologists as it typically presents tractable systems for unpicking the eco‐evolutionary processes driving community assembly. In general, two recurring themes are of central theoretical interest. First, immigration, diversification, and extinction typically depend on island geographical properties (e.g., area, isolation, and age). Second, predictable ecological and evolutionary trajectories readily occur after colonization, such as the evolution of adaptive trait syndromes, trends toward specialization, adaptive radiation, and eventual ecological decline. Hypotheses such as the taxon cycle draw on several of these themes to posit particular constraints on colonization and subsequent eco‐evolutionary dynamics. However, it has been challenging to examine these integrated dynamics with traditional methods. Here, we combine phylogenomics, population genomics and phenomics, to unravel community assembly dynamics among Pheidole (Hymenoptera, Formicidae) ants in the isolated Fijian archipelago. We uphold basic island biogeographic predictions that isolated islands accumulate diversity primarily through in situ evolution rather than dispersal, and population genomic support for taxon cycle predictions that endemic species have decreased dispersal ability and demography relative to regionally widespread taxa. However, rather than trending toward island syndromes, ecomorphological diversification in Fiji was intense, filling much of the genus‐level global morphospace. Furthermore, while most endemic species exhibit demographic decline and reduced dispersal, we show that the archipelago is not an evolutionary dead‐end. Rather, several endemic species show signatures of population and range expansion, including a successful colonization to the Cook islands. These results shed light on the processes shaping island biotas and refine our understanding of island biogeographic theory.

The Neotropical fruit fly Drosophila paulistorum (Diptera: Drosophilidae) is a species complex in statu nascendi comprising six reproductively isolated semispecies, each harboring mutualistic Wolbachia strains. Although wild type flies of each semispecies are isolated from the others by both pre- and postmating incompatibilities, mating between semispecies and successful offspring development can be achieved once flies are treated with antibiotics to reduce Wolbachia titer. Here we use RNA-seq to study the impact of Wolbachia on D. paulistorum and investigate the hypothesis that the symbiont may play a role in host speciation. For that goal, we analyze samples of heads and abdomens of both sexes of the Amazonian, Centro American and Orinocan semispecies of D. paulistorum. We identify between 175 and 1192 differentially expressed genes associated with a variety of biological processes that respond either globally or according to tissue, sex or condition in the three semispecies. Some of the functions associated with differentially expressed genes are known to be affected by Wolbachia in other species, such as metabolism and immunity, whereas others represent putative novel phenotypes involving muscular functions, pheromone signaling, and visual perception. Our results show that Wolbachia affect a large number of biological functions in D. paulistorum, particularly when present in high titer. We suggest that the significant metabolic impact of the infection on the host may cause several of the other putative and observed phenotypes. We also speculate that the observed differential expression of genes associated with chemical communication and reproduction may be associated with the emergence of pre- and postmating barriers between semispecies, which supports a role for Wolbachia in the speciation of D. paulistorum.

The West Palearctic species of Rhoptromeris are revised. A total of 11 species are recognised as valid in this region, including four newly described species: Rhoptromeris dichromata sp. nov., Rhoptromeris koponeni sp. nov., Rhoptromeris leptocornis sp. nov. and Rhoptromeris macaronesiensis sp. nov. Eucoila luteicornis Ionescu, 1959 is synonymised with Rhoptromeris heptoma (Hartig, 1840) syn. nov. A checklist of the Holarctic Rhoptromeris is presented and an identification key to the West Palearctic species is provided. www.zoobank.org/urn:lsid:zoobank.org:pub:8164332C-93E2-4E3F-A408-F5FF5DFB366E

Ancistrocerus waldenii waldenii (Viereck 1906) (Hymenoptera: Vespidae, Eumeninae), a new addition to the fauna of Greenland