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Vazquez-Dominguez, E.

Publications and source records attributed to Vazquez-Dominguez, E..

4 recordsLinked to original sources

Concordant yet unique neutral and adaptive genomic responses to anthropogenically modified landscapes in Rhinella horribilis

Anthropized environments are significantly challenging for wild species. Rapid adaptation to such habitats is thus key for their long-term persistence. Deciphering the environmental factors associated with species tolerance to modified habitats is fundamental for understanding the genetic and connectivity patterns of individuals and the local adaptation of their populations. We studied the Giant Toad, Rhinella horribilis, from two landscapes with distinct levels of anthropogenic habitat modification, assessed their genomic diversity, structure and connectivity with ddRAD-seq genomic data, identified potential outlier loci and their relationship with environmental and physicochemical water variables, and evaluated if populations from the two study sites showed signals of parallel adaptation. Both concordant and unique patterns were found regarding landscape factors and genotype-environment associations related with the degree of anthropic modification between landscapes. Genomic structure and connectivity were significantly associated with the presence of temporary water bodies, low vegetation cover, high humidity, solar radiation, and temperature. Notably, we identified both shared and distinct outlier SNPs and annotated functional genes for the two landscapes. Genes were enriched for biological processes and metabolic pathways, which were in turn correlated with environmental and physicochemical water variables. Genes and metabolic pathways were associated mainly with embryonic development, sexual maturation and immune responses. Studies such as this one, in an often-disregarded species, illustrate how parallel and un-parallel adaptive landscape genomic patterns arise in the stressful conditions of anthropized habitats.

evolutionary biology↗

Urban colonization of invasive species on islands: Mus musculus and Rattus rattus genetics of establishment on Cozumel island

Humans and wildlife experience complex interactions in urban ecosystems, favoring the presence of commensal species, among which invasive species are particularly successful. Rodents are the main vertebrate group introduced to oceanic islands, where the invasion process and dispersal patterns strongly influence their evolutionary and genetic patterns. We evaluated the house mouse Mus musculus and the black rat Rattus rattus on Cozumel island, Mexico. We assessed genetic diversity and structure, connectivity, gene flow, relatedness and bottleneck signals based on microsatellite loci. Our findings show that the constant introduction of individuals of different origins to the island promotes high allelic diversity and the effective establishment of migrants. We identified a clear genetic structure and low connectivity for the two species, tightly linked with anthropogenic and urban features. Moreover, we found M. musculus has a particularly restricted distribution within the city of San Miguel Cozumel, whilst its genetic structure is associated with the historical human population growth pulses accompanying the urbanization of the city. At the fine-scale genetic level, the main urban drivers of connectivity of the house mouse were both the impervious land surfaces, i.e. the urban landscape, and the informal commerce across the city (a proxy of resources availability). Chances of a secondary invasion to natural environments have been relatively low, which is crucial for the endemic taxa of the island. Nonetheless, improving urban planning to regulate future expansions of San Miguel Cozumel is of the outmost importance in order to prevent these invasive species to disperse further.

evolutionary biology↗

Complex genetic patterns and distribution limits mediated by native congeners of the worldwide invasive red-eared slider turtle

Non-native (invasive) species offer a unique opportunity to study the geographic distribution and range limits of species, wherein the evolutionary change driven by interspecific interactions between native and non-native closely related species is a key component. The red-eared slider turtle, Trachemys scripta elegans (TSE), has been introduced and successfully established worldwide. It can coexist with its native congeners T. cataspila, T. venusta and T. taylori in Mexico. We performed comprehensive fieldwork, executed a battery of genetic analyses and applied a novel species distribution modeling approach to evaluate their historical lineage relationships and contemporary population genetic patterns. Our findings support the historical common ancestry between native TSE and non-native (TSEalien), while also highlighting the genetic differentiation of the exotic lineage. Genetic patterns are associated with their range size/endemism gradient, the microendemic T. taylori showed significant reduced genetic diversity and high differentiation, whereas TSEalien showed the highest diversity and signals of population size expansion. Counter to our expectations, lower naturally occurring distribution overlap and little admixture patterns were found between and its congeners, exhibiting reduced gene flow and clear genetic separation across neighboring species despite having zones of contact. We demonstrate that these native Trachemys species have distinct climatic niche suitability, likely preventing establishment of and displacement by the non-native TSE. Additionally, we found major niche overlap between TSEalien and native species worldwide, supporting our prediction that sites with closer ecological optima to the invasive species have higher establishment risk than those that are closer to the niche-center of the native species.

evolutionary biology↗

Six percent loss of genetic variation in wild populations since the industrial revolution

Genetic variation underpins population fitness and adaptive potential1,2. Thus it plays a key role in any species probability of long-term persistence, particularly under global climate change. Genetic variation can be lost in a single generation but its replenishment may take hundreds of generations3. For that reason safeguarding genetic variation is considered fundamental to maintaining biodiversity, and is an Aichi Target for 20204. As human activities are driving declines in many wild populations5, genetic variation is also likely declining. However the magnitude of ongoing genetic variation loss has not been assessed, despite its importance. Here we show a 6% decline in within-population genetic variation of wild organisms since the industrial revolution. The erosion of genetic variation has been most severe for island species, with an 18% average decline. We also identified several key taxonomic and geographic information gaps that must be urgently addressed. Our results are consistent with single time-point meta-analyses that indicated genetic variation is likely declining 6,7. However, our results represent the first confirmation of a global decline, and estimate of the magnitude of the genetic variation lost from wild populations.

genetics↗