Publications by authors named "Ricardo A Ojeda"

The European rabbit is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of Argentina. The Adaptive Flexibility Hypothesis states that populations at the range edge (new populations) will exhibit greater flexibility in the use of resources compared with populations located in the range core (older populations). The objective of this work was to compare the rabbit's use of spatial and trophic resources in relation to the establishment time of their populations.

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Rodentia has a high species number and chromosomal variability. The South American genus Akodon is one of the most speciose muroids, with more than 40 species included in several species groups. Here, we characterize cytogenetically specimens of Akodon from central-western Argentina.

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Article Synopsis
  • - Natural history museums hold important specimens, samples, and data that help us understand the natural world.
  • - A recent commentary discusses the need for more compassionate collection methods for specimens in these museums.
  • - It raises the question of whether it's feasible to entirely stop the collection of whole animal specimens in the future.
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Rodents are an important component of South America fauna. Their high diversity has motivated researchers to continually review their taxonomy, genetic diversity, species limits, and phylogenetic relationships. Here, we applied DNA-barcodes for assessing the taxonomic and genetic diversity in the two major lineages of South American rodents: caviomorphs and sigmodontines.

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We analyzed the geographic variation in cranial morphology of the Southern Mountain Cavy, , throughout of its distributional range. Our analysis allows us to recognize three geographically allopatric morphotypes. These morphotypes differ in the general size and shape of the skull and discrete morphological traits of the zygomatic arch, palate and mesopterygoid fossa.

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Article Synopsis
  • * The study examined the genome of both rodents, finding support for genome expansion primarily due to repetitive elements rather than whole genome duplication.
  • * Repetitive sequences were scarce in areas of the genome that are actively transcribed, leading to questions about their role in chromosomal changes and potential effects on the species' adaptation to high-salt diets.
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