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Avila, L. J.

Publications and source records attributed to Avila, L. J..

4 recordsLinked to original sources

Cryptic diversification proceeds despite historical and contemporary hybridization in Patagonian ants

Understanding how independently evolving lineages arise despite ongoing gene flow remains a central question in evolutionary biology. Although genomic studies increasingly suggest that hybridization can accompany diversification, empirical evidence from ecologically dominant insect groups remains limited. Here, we present the first population-scale phylogenomic analysis of Patagonian ants, sampling Dorymyrmex across approximately 450,000 km2. Using genome-wide SNPs, coalescent phylogenetics, phylogenetic networks, demographic modelling, species delimitation, and genome scans, we reconstruct the evolutionary history of this widespread genus. We discovered extensive cryptic diversity with strong genomic differentiation and detected both recent and historical hybridization, demonstrating that substantial genomic divergence accumulated despite recurrent gene flow events. Genome scans further identify candidate loci associated with adaptation to Patagonias contrasting environments, suggesting that ecological divergence contributed to lineage diversification. Our results show that cryptic diversification can proceed despite recurrent gene flow, supporting hybridization as an integral component of the diversification process. More broadly, this study illustrates how genome-scale data can reveal hidden biodiversity and the evolutionary processes shaping it in ecologically important but genomically understudied taxa.

evolutionary biology↗

An integrative multi-approach workflow resolves species limits in the southernmost members of the Liolaemus kingii group (Squamata: Liolaemini)

Recent conceptual and methodological advances have enabled an increasing number of studies to address the problem of species delimitation in a comprehensive manner. This is of particular interest in cases of species whose divergence times are recent, where the conclusions obtained from a single source of evidence can lead to the incorrect delimitation of entities or assignment of individuals to species. The southernmost species of the Liolaemus kingii group (namely L. baguali, L. escarchadosi, L. sarmientoi, L. tari and the candidate species L. sp. A) show widely overlapping distributions as well as recent mitochondrial divergences, thus phylogenetic relationships and species boundaries are ambiguous. Here we use a comprehensive approach to assess species limits and corroborate their status as independent lineages through the use of four sources of molecular and morphological information (mitochondrial cytochrome-b, nuclear sequences collected by ddRADseq, and linear, meristic and landmark-based morphometrics). We found concordance among the different datasets, but signs of admixture were detected between some of the species. Our results indicate that the L. kingii group can serve as a model system in studies of diversification accompanied by hybridization in nature. We emphasize the importance of using multiple lines of evidence in order to solve evolutionary stories, and minimizing potential erroneous results that may arise when relying on a single source of information.

evolutionary biology↗

Is the replication crisis a problem for biologists? A geometric morphometric approach.

Replicability of findings is the key factor of scientific reliability. However, literature on this topic is scarce and apparently taboo for large scientific areas. Some authors named the failure to reproduce scientific findings replication crisis. Geometric morphometrics, a vastly used technique, is especially silent on replication crisis concern. Nevertheless, some works pointed out that sharing morphogeometric information is not a trivial fact, but need to be careful and meticulous. Here, we investigated the replicability of geometric morphometrics protocols on complex shapes and measurement error extension in three different types of taxa, as well as the potentiality of these protocols to discriminate among closely related species. We found a wide range of replication error that contributed from 19.5% to 60% of the total variation. Although, measurement error decreased with the complexity of the quantified shape, it often maintained high values. All protocols were able to discriminate between species, but more morphogeometric information does not imply better performance. We present evidence of replication crisis in life sciences and highlight the need to explore in deep different sources of variation that could lead to low replicability findings. Lastly, we enunciate some recommendations in order to improve the replicability and reliability of scientific findings.

scientific communication and education↗

How important is it to consider lineage diversification heterogeneity in macroevolutionary studies: lessons from the lizard family Liolaemidae

Macroevolutionary studies commonly apply multiple models to test state-dependent diversification. These models track the association between states of interest along a phylogeny, but they do not consider whether independent shifts in character states are associated with shifts in diversification rates. This potentially problematic issue has received little theoretical attention, while macroevolutionary studies implementing such models in increasing larger scale studies continue growing. A recent macroevolutionary study has found that Andean orogeny has acted as a species pump driving diversification of the family Liolaemidae, a highly species-rich lizard family native to temperate southern South America. This study approaches a distribution-dependent hypothesis using the Geographic State Speciation and Extinction model (GeoSSE). However, more recent analyses have shown that there is a clear heterogeneous diversification pattern in the Liolaemidae, which likely biased the GeoSSE analysis. Specifically, we show here that there are two shifts to accelered speciation rates involving species groups that were classified as "Andean" in their distributions. We demonstrate that this GeoSSE result is meaningless when heterogeneous diversification rates are included. We use the lizard family Liolaemidae to demonstrate potential risks of ignoring clade-specific differences in diversification rates in macroevolutionary studies.

evolutionary biology↗