Biology subjects

Noguerales, V.

Publications and source records attributed to Noguerales, V..

7 recordsLinked to original sources

bioRxiv2025

Homoploid hybrid speciation between cryptic species of a hidden snout weevil

Hybridisation may generate a variety of evolutionary outcomes, including novel hybrid species without a change in ploidy. Within this process, referred to as homoploid hybrid speciation (HHS), selection on recombinant traits is often invoked as the driver of reproductive isolation (RI) between hybrid and parental species. However, our understanding of the temporal, geographic and phenotypic dimensions within which hybrid populations evolve RI against parental species is still limited. Here, we describe HHS within a beetle species complex that presents no obvious phenotypical or ecological differences among hybrid and parental species, and where all occur sympatrically. Demographic modelling supports hybrid speciation, where the hybrid lineage originated from historical admixture between parental lineages. Genome-wide estimates of heterozygosity and individual-based simulations of hybrid speciation provide further support for an ancient, rather than recent origin of the hybrid species. We leverage geographic patterns of genomic relatedness between hybrid and parental individuals to identify the likely origin within a hybrid swarm that was geographically isolated from both parental species. We argue that hybridisation is not just a driver of speciation, but may also act as a facilitator by enhancing the pathway to RI above that expected within a strictly allopatric model.

evolutionary biology↗

bioRxiv2024

Understanding the mechanisms underlying microbiota variation in wild tick populations

Ticks are fascinating arthropods that have developed a unique blood-feeding lifestyle, making them intriguing subjects for understanding how they adapt to living with vertebrate hosts, their ability to transmit diseases, and their versatile roles in the ecosystem. Recent research highlights how significantly microbes impact the evolution of ticks, suggesting a genetic link to their hosts. These microbial partnerships are vital in improving tick nutrition, metabolism, reproduction, and overall survival, highlighting their important role as vectors in diverse ecological environments. In this study, we took a close look at the microbial communities present in three wild tick species--Hyalomma lusitanicum, Rhipicephalus sanguineus, and Rhipicephalus bursa--collected from several sites across central Spain. Through high-throughput DNA sequencing of the 16S rRNA gene, we discovered a complex and diverse microbiota largely composed of Proteobacteria, Bacteroidota, and Firmicutes. While all species exhibited a shared core microbiota, notable differences in microbial composition and network microbial interactions suggest that each species may be influenced by ecological and evolutionary factors shaping their microbiota. These insights deepen our understanding of the complex relationships between ticks, their microbiota, and the surrounding environment, which can inform better strategies for managing vectors and controlling pathogens.

genomics↗

bioRxiv2024

Wolbachia as agents of extensive mtDNA lineage sharing between species through multiple infection

Wolbachia can manipulate arthropod host reproduction, triggering the homogenisation of mtDNA variation within species and introgression between hybridising species through indirect selection. While fixation within species of mtDNA variants linked to Wolbachia infections has been documented, a broader understanding of the potential consequences of Wolbachia infection through hybridisation is limited. Here we evaluate Wolbachia transmission through hybridisation as a mechanistic explanation for extensive mtDNA paraphyly between two species of iron-clad beetle (Zopheridae). Our analyses reveal a complex pattern of mitochondrial variation, supporting the introgression of at least five mtDNA lineages from Tarphius canariensis into T. simplex, in a background of a shared Wolbachia infection across both species. Genetic clustering and demographic simulations reveal a clear pattern of nuclear differentiation between species, a limited signature of historical gene flow, and the eastwards range expansion of T. simplex across the existing distribution of T. canariensis. These results are consistent with hybridisation during early stages of secondary contact, during which Wolbachia infection facilitated recurrent mtDNA introgression events. These results highlight the complex restructuring of mitochondrial differentiation across invertebrate species that can result from bacterial endosymbiotic infections, a phenomena with potentially profound impacts for the disciplines of phylogeography and species delimitation.

evolutionary biology↗

bioRxiv2024

Genetic legacies of mega-landslides: cycles of isolation and contact across flank collapses in an oceanic island

Catastrophic flank collapses are recognised as important drivers of insular biodiversity dynamics, through the disruption of species ranges and subsequent allopatric divergence. However, little empirical data supports this conjecture, with their evolutionary consequences remaining poorly understood. Using genome-wide data within a population genomics and phylogenomics framework, we evaluate how mega-landslides have impacted evolutionary and demographic history within a species complex of weevils (Curculionidae) within the Canary island of Tenerife. We reveal a complex genomic landscape, within which individuals of single ancestry were sampled in areas characterised by long-term geological stability, relative to the timing of flank collapses. In contrast, individuals of admixed ancestry were almost exclusively sampled within the boundaries of flank collapses. Estimated divergence times among ancestral populations aligned with the timings of mega-landslide events. Our results provide first evidence for a cyclical dynamic of range fragmentation and secondary contact across flank collapse landscapes, with support for a model where this dynamic is mediated by Quaternary climate oscillations. The context within which we reveal climate and topography to interact cyclically through time to shape the geographic structure of genetic variation, together with related recent work, highlights the importance of topoclimatic phenomena as an agent of diversification within insular invertebrates.

evolutionary biology↗

bioRxiv2021

Genomic evidence of speciation by fusion linked to trophic niche expansion in a recent radiation of grasshoppers

Post-divergence gene flow can trigger a number of creative evolutionary outcomes, ranging from the transfer of beneficial alleles across species boundaries (i.e., adaptive introgression) to the formation of new species (i.e., hybrid speciation). While neutral and adaptive introgression has been broadly documented in nature, hybrid speciation is assumed to be rare and the evolutionary and ecological context facilitating this phenomenon still remains controversial. Through combining genomic and phenotypic data, we evaluate the hypothesis that the dual feeding regime (scrub legumes and gramineous herbs) of the taxonomically controversial grasshopper Chorthippus saulcyi algoaldensis resulted from hybridization between two sister taxa that exhibit contrasting host-plant specializations: C. binotatus (scrub legumes) and C. saulcyi (gramineous herbs). Genetic clustering analyses and inferences from coalescent-based demographic simulations confirmed that C. s. algoaldensis represents a uniquely evolving lineage and supported the ancient hybrid origin of this taxon (ca. 1.4 Ma), which provides a mechanistic explanation for its broader trophic niche and sheds light on its uncertain phylogenetic position. We propose a Pleistocene hybrid speciation model where range shifts resulting from climatic oscillations can promote the formation of hybrid swarms and facilitate its long-term persistence through geographic isolation from parental forms in topographically complex landscapes.

genetics↗

bioRxiv2021

Image-based taxonomic classification of bulk biodiversity samples using deep learning and domain adaptation

Complex bulk samples of invertebrates from biodiversity surveys present a great challenge for taxonomic identification, especially if obtained from unexplored ecosystems. High-throughput imaging combined with machine learning for rapid classification could overcome this bottleneck. Developing such procedures requires that taxonomic labels from an existing source data set are used for model training and prediction of an unknown target sample. Yet the feasibility of transfer learning for the classification of unknown samples remains to be tested. Here, we assess the efficiency of deep learning and domain transfer algorithms for family-level classification of below-ground bulk samples of Coleoptera from understudied forests of Cyprus. We trained neural network models with images from local surveys versus global databases of above-ground samples from tropical forests and evaluated how prediction accuracy was affected by: (a) the quality and resolution of images, (b) the size and complexity of the training set and (c) the transferability of identifications across very disparate source-target pairs that do not share any species or genera. Within-dataset classification accuracy reached 98% and depended on the number and quality of training images and on dataset complexity. The accuracy of between-datasets predictions was reduced to a maximum of 82% and depended greatly on the standardisation of the imaging procedure. When the source and target images were of similar quality and resolution, albeit from different faunas, the reduction of accuracy was minimal. Application of algorithms for domain adaptation significantly improved the prediction performance of models trained by non-standardised, low-quality images. Our findings demonstrate that existing databases can be used to train models and successfully classify images from unexplored biota, when the imaging conditions and classification algorithms are carefully considered. Also, our results provide guidelines for data acquisition and algorithmic development for high-throughput image-based biodiversity surveys.

zoology↗

bioRxiv2017

Ecological drivers of body size evolution and sexual size dimorphism in short-horned grasshoppers (Orthoptera: Acrididae)

Sexual size dimorphism (SSD) is widespread and variable in nature. Although female-biased SSD predominates among insects, the proximate ecological and evolutionary factors promoting this phenomenon remain largely unstudied. Here, we employ modern phylogenetic comparative methods on 8 subfamilies of Iberian grasshoppers (85 species) to examine the validity of different models of evolution of body size and SSD and explore how they are shaped by a suite of ecological variables (habitat specialization, substrate use, altitude) and/or constrained by different evolutionary pressures (female fecundity, strength of sexual selection, length of the breeding season). Body size disparity primarily accumulated late in the history of the group and did not follow a Brownian motion pattern, indicating the existence of directional evolution for this trait. We found support for the converse of Renschs rule across all taxa but not within the two most speciose subfamilies (Gomphocerinae and Oedipodinae), which showed an isometric pattern. Our results do not provide support for the fecundity or sexual selection hypotheses and we did not find evidence for significant effects of habitat use. Contrary to that expected, we found that species with narrower reproductive window are less dimorphic in size than those that exhibit a longer breeding cycle, suggesting that male protandry cannot solely account for the evolution of female-biased SSD in Orthoptera. Our study highlights the need to consider alternatives to the classical evolutionary hypotheses when trying to explain why in certain insect groups males remain small.

evolutionary biology↗