Biology subjects

Mori, G. M.

Publications and source records attributed to Mori, G. M..

6 recordsLinked to original sources

bioRxiv2026

Range shifts of Eastern South American mangroves in a changing climate

As climate changes, habitat suitability for multiple taxa are also expected to change. In recent years, mangrove latitudinal range expansion has been linked to increasing temperatures and reduced freezing in temperate regions, happening mainly through encroachment into saltmarshes. The range limit of mangrove forests in Eastern South America has not seen drastic changes in the last four decades, despite trends of increased temperature and the seemingly favorable direction of the Brazilian Current. Here, we investigate if and how the distribution of South-Atlantic mangrove forests may respond to different scenarios of climate change. To do this, we combine ecological niche modelling with propagule dispersal simulations to understand the roles of climate and ocean currents in defining the austral limits of South-Atlantic American mangroves. Our results indicate that minimum sea surface temperature strongly constrains habitat suitability beyond the current distribution of mangroves (28{degrees}2868" S), while dispersal processes heavily limit propagule stranding beyond 35{degrees} S. The Brazil-Malvinas currents confluence zone creates steep temperature gradients and an oceanographic barrier that makes the latitudinal expansion of mangroves unlikely in this region, even in future scenarios of heating climate. We found no evidence of current nor future poleward expansion of mangroves, but total mangrove area has increased in Brazil over the last decades, likely due to landward migration, but anthropogenic interference and urban expansion may restrict this process, leading to coastal squeeze. Under scenarios where both landward and poleward migration are limited, South American mangroves may face increasing vulnerability, with potential impacts on the several ecological, biogeochemical and social cycles they support. Our results contribute to leading hypotheses of climate restriction and shed light on the role of ocean currents in South America, helping to explain why the poleward expansion reported in other regions has not yet been observed in the South-Atlantic mangrove range limit.

ecology↗

bioRxiv2025

Multiple mating predicts queen reproductive output in the polygynous Neotropical trap-jaw ant, Odontomachus chelifer (Formicidae: Ponerinae)

The factors that influence the organisms ability to reproduce are diverse. In ants, social structure may contribute to queens Reproductive Output (RO), alongside environmental conditions and genetic attributes. Polygynous species like the Neotropical trap-jaw ant, Odontomachus chelifer, are valuable biological systems to investigate the contribution of these factors to the RO of queens. We hypothesize that O. chelifer queens RO increases with (1) higher multiple mating (polyandry) per queen; (2) higher queen heterozygosity; (3) greater food availability. We sampled workers from 18 colonies from the Brazilian Cerrado savanna (15 workers per colony) and used eight microsatellites to infer the number of male mates per queen, queens heterozygosity, and the proportion of offspring produced per queen. The latter was used to calculate the index of deviation from even offspring production (DEM) among queens. Arthropod communities from sampling sites were used as a proxy for food resources availability. We evaluated the relationships between DEM and the predictor variables using bivariate generalized linear models. Our results showed a positive relationship between polyandry and DEM (Coefficient = 0.41, P < 0.001). It suggests that the number of male mates likely benefits queen productivity, highlighting the role colony structure plays in the fitness of individual queens within O. chelifer colonies. Our findings did not support the remaining hypotheses. This work illuminates the role of social forms in evolutionary processes in ants, making way for similar studies in different social insects and contributes to a better understanding of the reproductive traits of trap-jaw ants.

evolutionary biology↗

bioRxiv2022

Differential adaptive potential and vulnerability to climate-driven habitat loss in Brazilian mangroves

Geographic and environmental differences have been identified as factors influencing Brazilian mangrove trees genetic diversity. Geographically, distinct species have convergent spatial genetic structures, indicating a limited gene flow between northern and southern populations. Environmentally, genomic studies and common garden experiments have found evidence of local adaptations along the latitudinal gradient of the Brazilian coast. However, little is known about how such adaptive heterogeneity could be affected by a rapidly changing climate in the coming decades, and the combination of deforestation and climate-induced habitat loss may affect these forests and their genetic diversity. Here, we applied two genomic-environmental association methods to model the turnover of potentially adaptive alleles for two dominant mangrove trees: Avicennia germinans and A. schaueriana. We analyzed a total of 134 individuals from six populations of A. germinans and ten populations of A. schaueriana spanning the Brazilian coast from 1 {degrees}S to 28 {degrees}S. Gradient forest models identified temperature-related variables as the most important predictors for A. germinans outlier loci, whereas both temperature and precipitation were important for A. schaueriana. We modeled allele frequencies and projected them for future climatic scenarios to estimate adaptively driven vulnerability. We assessed climate-driven habitat loss through climate-only distribution models and calculated annual deforestation rates for each sampled region. Finally, to assess the vulnerability of individual populations, we combined the environmental suitability, deforestation data, and adaptive vulnerability projections. For both species, subtropical populations presented a higher vulnerability than equatorial populations to climate-driven habitat loss. We also identified deforestation rates at the sampled sites that were alarmingly higher than the global average mangrove deforestation rate. Our results provide improved estimates of the impacts of ongoing climate change and human-caused habitat loss on the distribution of mangroves and highlight the importance of site-based conservation strategies that consider individual subtropical and equatorial mangrove forests.

evolutionary biology↗

bioRxiv2021

Natural history of two carpenter ants, Camponotus renggeri and C. rufipes (Hymenoptera: Formicidae), in an Atlantic Forest reserve

Widespread species face a wide variety of environmental challenges and their morphology, behavior, and natural history may change across their range. However, not rarely, natural history research is restricted to one or few locations. That is the case for Camponotus renggeri and C. rufipes. Both species occur across South America in different ecosystems, but most research on these species is restricted to the Brazilian savanna, known as Cerrado. Here, we describe the foraging area, nesting habits, and activity schedule of C. renggeri and C. rufipes in an Atlantic Forest reserve in SE Brazil. C. renggeri foraged exclusively during nighttime and C. rufipes remained active throughout the day, but with little intensity during daylight hours. Most nests of both species were composed of dry straw, and average foraging areas were 0.91 m2 for C. renggeri and 1.79 m2 for C. rufipes. Inferred intraspecific foraging areas of nearby nests overlapped, especially for C. renggeri. Our findings reinforces the importance of natural history and what it adds to our knowledge on the ecology and behavior of C. renggeri and C. rufipes in Atlantic Forest.

ecology↗

bioRxiv2020

Geographic and environmental contributions to genomic divergence in mangrove forests

Assessing the relative importance of geographical and environmental factors to the spatial distribution of genetic variation can provide information about the processes that maintain genetic variation in natural populations. With a globally wide but very restricted habitat distribution, mangrove trees are a useful model for studies aiming to understand the contributions of these factors. Mangroves occur along the continent-ocean interface of tropical and subtropical latitudes, regions considered inhospitable to many other types of plants. Here, we used landscape genomics approaches to investigate the relative contributions of geographical and environmental variables to the genetic variation of two black mangrove species, Avicennia schaueriana and Avicennia germinans, along the South American coast. Using single nucleotide polymorphisms, our results revealed an important role of ocean currents and geographical distance in the gene flow of A. schaueriana and an isolation-by-environment pattern in the organization of the genetic diversity of A. germinans. Additionally, for A. germinans, we observed significant correlations between genetic variation with evidence of selection and the influence of precipitation regimens, solar radiation and temperature patterns. These discoveries expand our knowledge about the evolution of mangrove trees and provide important information to predict future responses of coastal species to the expected global changes during this century.

genomics↗

bioRxiv2018

Environment-driven genomic and trait divergence in a neotropical mangrove highlight differential sensitivities to climate change

Local adaptation is often a product of environmental variations in the geographical space and has implications for biodiversity conservation. We investigated the role of latitudinal heterogeneity in climate on the organization of genetic and phenotypic variation in the dominant coastal tree, Avicennia schaueriana. In a common garden experiment, samples from an equatorial region, marked by rainy/dry seasons, accumulated less biomass, showed lower stomatal conductance and transpiration, narrower xylem vessels, smaller leaves and higher reflectance of long wavelengths (red light) on the stem epidermis, than samples from a subtropical region, marked by warm/cold seasons. Transcriptome differences identified between trees sampled under field conditions at equatorial and subtropical sites, were enriched in functional categories as responses to temperature, solar radiation, water deficit, photosynthesis and cell wall biosynthesis. The diversity based on thousands of SNP loci revealed a north-south genetic structure. Remarkably, signatures of selection were identified in loci associated with photosynthesis, anthocyanin accumulation and the responses to osmotic and hypoxia stresses. Our results suggest the existence of divergence in key resource-use characteristics, likely driven by climate seasonality, based on water-deficit and solar radiation. These findings provide a basis for conservation plans and for predictions for coastal plant responses to climate change.

plant biology↗