Person: Aragón Carrera, Pedro
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First Name
Pedro
Last Name
Aragón Carrera
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Biológicas
Department
Biodiversidad, Ecología y Evolución
Area
Zoología
Identifiers
6 results
Search Results
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Item Cryptic speciation in gentoo penguins is driven by geographic isolation and regional marine conditions: Unforeseen vulnerabilities to global change(Diversity and Distributions, 2020) Rodríguez Pertierra, Luis; Segovia, Nicolas I.; Noll, Daly; Martinez, Pablo; Pliscoff, Patricio; Barbosa Alcón, Andrés; Aragón Carrera, Pedro; Raya Rey, Andrea; Pistorius, Pierre; Trathan, Phil; Polanowski, Andrea; Bonadonna, Francesco; Le Bohec, Céline; Bi, Ke; Wang-Claypool, Cynthia Y.; González-Acuña, Daniel; Dantas, Gisele P. M.; Bowie, Rauri C. K.; Poulin, Elie; Vianna, Juliana A.Aim: The conservation of biodiversity is hampered by data deficiencies, with many new species and subspecies awaiting description or reclassification. Population genomics and ecological niche modelling offer complementary new tools for uncovering functional units of phylogenetic diversity. We hypothesize that phylogenetically delineated lineages of gentoo penguins (Pygoscelis papua) distributed across Antarctica and sub-Antarctic Islands are subject to spatially explicit ecological conditions that have limited gene flow, facilitating genetic differentiation, and thereby speciation processes. Location: Antarctica and sub-Antarctic area. Methods: We identify divergent lineages for gentoo penguins using ddRAD-seq and mtDNA, and generated species distribution models (SDMs) based on terrestrial and marine parameters. Results: Analyses of our genomic data supports the existence of four major lineages of gentoo penguin: (i) spanning the sub-Antarctic archipelagos north of the Antarctic Polar Front (APF); (ii) Kerguelen Island; (iii) South America; and (iv) across maritime Antarctic and the Scotia Arc archipelagos. The APF, a major current system around Antarctica, acts as the most important barrier separating regional sister lineages. Our ecological analyses spanning both the terrestrial (breeding sites) and marine (feeding sites) realms recover limited niche overlap among the major lineages of gentoo penguin. We observe this pattern to correspond more closely with regional differentiation of marine conditions than to terrestrial macroenvironmental features. Main conclusions: Recognition of regional genetic lineages as discrete evolutionary entities that occupy distinct ecological niches and also differ morphologically should be considered a priority for conservation. Gentoo penguins provide a good example of how conservation policy can be directly impacted by new insights obtained through the integration of larger genomic datasets with novel approaches to ecological modelling. This is particularly pertinent to polar environments that are among the most rapidly changing environments on earth.Item Antipredator responses of the morphs of an amphibian species match their diferential predation pressures(Behavioral Ecology and Sociobiology, 2022) Zamora Camacho, Francisco Javier; Aragón Carrera, PedroEscape efciency typically relies on locomotor performance, which depends on morphology. Moreover, fight initiation distance (FID, the distance from an approaching predator at which a prey starts fight) is behaviourally adjusted to minimize the costs of escape. When conspecifcs with distinct heritable traits are subjected to diferential predator pressure, specialized antipredator strategies may evolve. Phenotypic variants associated to sex and other polymorphisms may be susceptible of sufering predator attacks to diferent extents. Herein, we used striped and mottled morphs of the polymorphic frog Discoglossus galganoi to test for diferences between morphs and sex in predation pressure and concomitant antipredator responses. Firstly, we used plasticine models to assess predation pressure (by a natural set of local predators ranging from snakes to birds and mammals) on both striped and mottled morphs. Then, we tested for diferences on morphology, locomotor performance, FID, and their interactions between morphs and sexes. Striped models were more often attacked, which suggests that striped frogs are under stronger predation pressure. Morphology was similar between morphs, and so was locomotor performance. However, FID was greater in striped than in mottled individuals. Contrastingly, sexes did not difer in FID, but males had longer limbs and greater locomotor performance than females, which is common in other taxa. Nonetheless, both sexes displayed similar FID. Finally, FID was greater in larger individuals, but unrelated to locomotor performance. These results support the hypothesis that diferent antipredator strategies are tuned to divergent predation risk sufered by sexes and morphs.Item Mecanismos para reducir los costes derivados de los encuentros agresivos en los machos de la lagartija serrana ("Lacerta monticola")(2004) Aragón Carrera, Pedro; Martín Rueda, José; López Martínez, PilarLa presente tesis estudia los mecanismos que intervienen reduciendo los costes que suponen los encuentros agresivos entre los machos de L. Monticola, teniendo en cuenta factores como el de intruso-residente, familiaridad, habilidad competitiva y estacionalidad. Los machos de L.monticola son capaces detectar y discriminar sus propias secreciones femorales de las de otros machos a partir señales quimicas exclusivamente. Este hecho indica la utilización de las secreciones femorales en la comunicación intraespecifica. El uso del espacio y la exploración quimica de los machos de L.monticola en presencia de señales quimicas procedentes de otros machos conespecificos depende del tamaño relativo. Esto sugiere que son capaces de estimar la habilidad competitiva en relación con otros machos conespecíficos y en ausencia del emisor. Los machos de L.monticola son capaces de discriminar entre machos con especificos familiares y no familiares utilizando unicamente informacion quimica procedente de las secreciones femorales o los excrementos. El hecho de que los machos verdes sean de mayor tamaño, tengan mayor probabilidad de éxito en los ecuestres agonísticos, tengan areas más exclusivas frente a otros machos y un mayor grado de solapamiento con las hembras sugiere que la coloración verde podría actuar como señalizador de la habilidad competitiva. Los machos verdes presentan un solapamiento temporal mayor con otros machos que los machos marrones. A diferencia de los machos marrones, los machos verdes concentran el acceso a los recursos por la mañana lo que les podría permitir reducir los costes que implican las actividades conspicuas. Por otro lado, los machos marrones podrían tener que dispersar el acceso a los recursos de una forma oportunista. Las interacciones agonísticas, los niveles de actividad, el tamaño del area de campeo y el número de vecinos del mismo sexo decrecieron según se iba aproximando el periodo no reproductor en los machos pro no en las hembras. Estos resultados sugieren que el balance entre los costes y los beneficios es diferente en el periodo reproductor y no reproductor en los machos pero no en las hembras. El cambio gradual que se aprecie en los machos podría ser un mecanismo para reducir la frecuencia de las interacciones agonísticas.Item Niche models at inter‑and intraspecifc levels reveal hierarchical niche diferentiationin midwife toads(Scientific Reports, 2020) Rodríguez Rodríguez, Eduardo; Beltrán, Juan F.; Tejedo, Miguel; Nicieza, Alfredo G.; Llusia, Diego; Márquez, Rafael; Aragón Carrera, PedroVariation and population structure play key roles in the speciation process, but adaptive intraspecifc genetic variation is commonly ignored when forecasting species niches.Amphibians serve as excellent models for testing how climate and local adaptations shape species distributions due to physiological and dispersal constraints and long generational times. In this study, we analysed the climatic factors driving the evolution of the genus Alytes at inter- and intraspecifc levels that may limit realized niches.We tested for both diferences among the fve recognized species and among intraspecifc clades for three of the species (Alytes obstetricans, A. cisternasii, and A. dickhilleni). We employed ecological niche models with an ordination approach to perform niche overlap analyses and test hypotheses of niche conservatism or divergence. Our results showed strong diferences in the environmental variables afecting species climatic requirements.At the interspecifc level, tests of equivalence and similarity revealed that sister species were non-identical in their environmental niches, although they neither were entirely dissimilar. This pattern was also consistent at the intraspecifc level, with the exception of A. cisternasii, whose clades appeared to have experienced a lower degree of niche divergence than clades of the other species. In conclusion, our results support that Alytes toads, examined at both the intra- and interspecifc levels, tend to occupy similar, if not identical, climatic environments.Item Deconstructing the abundance–suitability relationship in species distribution modelling(Global Ecology and Conservation, 2020) Jiménez-Valverde, Alberto; Aragón Carrera, Pedro; Lobo, Jorge M.Aim: Local suitability estimated with species distribution models (SDMs) could indicate the maximum abundance attainable by species. Often the abundance–suitability relationship is wedge-shaped because species do not reach their maximum potential in every suitable location. We explore how SDM performance, the amount of information lost when converting continuous abundance into presence–absence data and species prevalence influence the abundance–suitability relationship. Location: Undefined. Time period: Undefined. Major taxa: Virtual species. Methods: Different abundance scenarios were simulated and converted into presence–absence maps. SDMs were parameterized using simulated predictors with different explanatory capacities. Quantile regressions were performed to characterize the abundance–suitability relationship. The strength of the wedge-shaped pattern was estimated using the difference in slopes between the 90th and 50th quantile lines, the goodness-of-fit of the 90th quantile regressions was calculated, and variation of both parameters was analysed as a function of SDM performance, prevalence and maximum abundance. Results: The degree of wedge shape was directly related to maximum abundance. It also depended on SDM quality; the higher the discrimination capacity, the less wedge-shaped the abundance–suitability relationship and higher the goodness-of-fit of the 90th quantile regressions. Prevalence exerted a significant effect on the shape of the relationship by influencing—together with maximum abundance—the extent of information loss. Main conclusions: SDMs cannot predict actual abundance even when the true determinants of abundance are included as predictors. Because presence–absence and abundance data are related but are different variables, wedge-shaped patterns are unavoidable. Discrimination capacity and prevalence affect the strength of the wedge-shaped pattern, so understanding their effects is necessary before any biological explanation is provided for the abundance–suitability relationship. Suitability maps derived from SDMs may transmit a false sense of precision at a local scale and should not be used as a perfect surrogate when abundance information is required.Item Niche differentiation between deeply divergent phylogenetic lineages of an endemic newt: implications for species distribution models(Zoology, 2020) Peñalver-Alcazar, Miguel; Jiménez-Valverde, Alberto; Aragón Carrera, PedroSpecies distribution models (SDMs) treat species as a single unit, neglecting intraspecific variation. Few studies address the impact of intraspecific variation on SDM performance, and none of them account for the well-known inter-algorithm variability in prediction performance. The endemic Iberian amphibian Lissotriton boscai comprises two geographically highly structured phylogenetic lineages, which allowed us to explore how intraspecific variation affects the overall performance of SDMs and the predicted ecological niche. We built species and lineage distribution models using three different presence-only algorithms. We also tested for niche overlap, niche equivalency and niche similarity, using an ordination technique. We found differences in the predicted potential distribution of the two lineages and the underlying environmental factors. Moreover, intraspecific differences in model predictive capacity existed irrespective of which algorithm was used to build the distribution models. This was coupled with lineages showing a low degree of niche overlap and occurring in relatively different environmental niches spaces. The intraspecific variation observed in L. boscai led to an improved intraspecific predictivity of the lineage level based-distribution models. There was partial spatial agreement between the niche overlap and independently reported secondary contact zones. Thus SDMs built only at the species level may be too naive to predict impacts of global change on species distributions.