Biology subjects

Mendoza, I.

Publications and source records attributed to Mendoza, I..

5 recordsLinked to original sources

bioRxiv2026

Overcoming software bottlenecks for scalable passive acoustic monitoring: insights from a global expert assessment

1.Passive acoustic monitoring (PAM) enables non-invasive sampling of wildlife across broad spatial, temporal and taxonomic scales. Its ongoing and widespread use has generated unprecedented volumes of acoustic data, shifting the primary bottleneck from data collection to the storage, processing, integration, and interpretation of PAM outputs. Although many software tools exist to address these challenges, differences in their design, scope, and usability often create fragmented and complex analytical workflows. To identify the key barriers and opportunities shaping the implementation of PAM surveys, we conducted a structured expert solicitation involving 30 international practitioners working across terrestrial and aquatic ecosystems. Experts identified and ranked their most critical pain points in current PAM workflows, spanning data storage, processing, and interpretation. The top challenge identified related to accurate species identification using deep learning and artificial intelligence (AI) models, especially in noisy soundscapes or for underrepresented taxa. Eight additional priority challenges included workflow fragmentation, limited availability of user-friendly analytical and visualisation tools, uneven access to software, manual validation bottlenecks, computational constraints, and difficulties in data handling, standardisation, and sharing. Participants also proposed practical mitigation strategies for these priority challenges, supported by step-by-step guidance to help overcome key barriers. Together, these insights provide a roadmap toward more scalable, open-access, and collaborative software systems, which are increasingly essential to realise the full potential of PAM in global biodiversity monitoring.

ecology↗

bioRxiv2025

Environmental stress amplifies competitive asymmetry and drives divergent hybrid zone outcomes

Community persistence depends on the balance between abiotic constraints and biotic interactions. Environmental stress can either sort species by physiological limits or amplify competitive asymmetries, producing coexistence, exclusion, or collapse. We tested these alternatives in two replicate hybrid swarms between orangethroat and orangebelly darters (Etheostoma pulchellum and E. radiosum spp. complex) with contrasting outcomes: long-term coexistence in the Blue River versus collapse in the Washita River. We combined critical-thermal-maximum (CTmax) assays with standardized feeding experiments to evaluate physiological tolerance, competitive exclusion, and stress-amplified competition. CTmax varied with river, sex, and body size but not consistently between species, indicating that local history and demography outweighed intrinsic physiological differences. In contrast, competition trials revealed strong, temperature-dependent asymmetries: E. pulchellum dominated in the cooler, stable Blue River, whereas E. radiosum spp. gained a foraging advantage under high temperatures in the warmer Washita River drainage. These results support the prediction that abiotic stress amplifies competitive asymmetries, flipping dominance and explaining divergent hybrid zone outcomes. More broadly, our study links hybrid zone dynamics to coexistence theory, showing that climate extremes can shift competitive balance and determine whether secondary contact results in persistence or loss.

evolutionary biology↗

bioRxiv2025

Physical and functional interactions of the potassium uptake protein HAK5 and the nitrate transporter NPF6.2 is critical for the mineral nutrition of Arabidopsis

Potassium (K+) starvation induces the expression of gene HAK5 encoding a high-affinity K+ uptake protein, but how plants perceive the K+ status and the signaling intermediaries involved in the response remains largely unknown. To identify key regulators of K+ nutrition in Arabidopsis, a genetic screen was performed using an pHAK5:LUC reporter line, and a mutant showing stable induction of the reporter under K+-sufficient conditions was isolated. Mapping-by-sequencing identified two linked mutations affecting genes involved in K+ and nitrate nutrition, namely a loss-of-function in the K+ uptake channel AKT1 and a gain-of-function allele of the nitrate transporter NPF6.2/NRT1.4 (NPF6.2V210M) that doubled the rate of nitrate transport. We report that the physical interaction of NPF6.2 and HAK5 transport proteins resulted in reciprocal interference. Co-expression in Xenopus oocytes of NPF6.2 with the regulatory kinase CIPK23 or the mutant protein NPF6.2V210M alone inhibited HAK5 transport, whereas HAK5 inhibited nitrate transport by NPF6.2 and NPF6.2V210M. We conclude that mutation NPF6.2V210M enhanced the nutritional defects associated to the loss of AKT1 function through the inhibition of HAK5. These findings evidence an intimate molecular crosstalk between transporters involved in the mineral nutrition of plants. The mutual interference when both transport systems are operative may represent a novel integrative regulatory mechanism in mineral nutrition.

plant biology↗

bioRxiv2022

Structure-Guided Identification of Critical Residues in the Vacuolar Na+,K+/H+ Antiporter NHX1 from Arabidopsis thaliana

Cation/Proton Antiporters (CPA) acting in all biological membranes help regulate the volume and pH of cells and of intracellular organelles. A key issue with these proteins is their structure-function relationships since they present intrinsic regulatory features that rely on structural determinants, including pH-sensitivity and the stoichiometry of ion exchange. Crystal structures are only available for prokaryotic CPA, whereas the eukaryotic ones have been modeled using the former as templates. Here we show an updated and improved structural model of the tonoplast-localized K+,Na+/H+ antiporter NHX1 of Arabidopsis as a representative of the vacuolar NHX family that is key to the accumulation of K+ into plant vacuoles. Conserved residues judged as functionally important were mutated and the resulting protein variants were tested for activity in the yeast Saccharomyces cerevisiae. Results indicate that residue N184 in the ND-motif characteristic of CPA1 could be replaced by the DD-motif of CPA2 family members with minimal consequences on activity, yet this residue may help to regulate the optimal pH range of the exchanger. Attempts to alter the electroneutrality of AtNHX1 by different combinations of amino acid replacements at N184, R353 and R390 residues resulted in inactive or partly active proteins with differential ability to control the vacuolar pH of the yeast.

plant biology↗

bioRxiv2020

Assessing short- and long-term variations in diversity, timing, and body condition of migratory frugivorous birds

Under current global change context, climate change is driving substantial phenological mismatches between plant species and the organisms that rely on them. Given that frugivorous birds are fundamental for forest regeneration, and most of them are migrant species, identifying the effect of global change over them must be a priority. In this study we have analysed changes in the composition, morphometry, and physical condition in an avian community at long- (40 years) and short time (seasonal) spans. Our findings indicate a profound transformation at practically every level of analysis. In 40 years, the avian community shows a 66% and 13% decrease of the wintering and seed-disperser species, respectively. Seasonal abundance peaks were advanced in 13 out of 15 species. In addition, we have found a significant 1.5% increase in the morphometric measurements of certain species, supporting findings in previous studies, and also a remarkable general decrease of body condition. Our results point towards land use changes and climate change as the main causes. If this influence continues to rise, biodiversity will likely be irreversibly altered, damaging crucial ecosystem functions such as animal-mediated seed dispersal and forest regeneration in particular.

ecology↗