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Arcones, A.

Publications and source records attributed to Arcones, A..

2 recordsLinked to original sources

Multidimensionality in the thermal niches of dung beetles could limit species' responses to temperature changes

Understanding the consequences of climate change requires understanding how temperature controls species responses across key biological aspects, as well as the coordination of thermal responses across these aspects. We study the role of temperature in determining the species diel, seasonal, and geographical occurrence, using dung beetles as a model system. We found that temperature has relatively low -but not negligible- effects in the three spatiotemporal scales, once accounting for alternative factors. More importantly, the estimated thermal responses were largely incongruent across scales. This shows that species have multidimensional thermal niches, entailing that adjustments to fulfil temperature requirements for one biological aspect, such as seasonal ontogenetic cycles, may result in detrimental effects on other aspects, like diel activity. These trade-offs can expose individuals to inadequate temperatures, reducing populations performance. Paradoxically, the relatively weak effects of temperature we found may have serious consequences for species responses to warming if temperature regulates essential aspects of species biology in divergent ways.

ecology

Mitochondrial substitution rates estimation for molecular clock analyses in modern birds based on full mitochondrial genomes

Abstractti Mitochondrial DNA (mtDNA) is a very popular resource in the study of evolutionary processes in birds, and especially to infer divergence times between lineages. These inferences rely on rates of substitution in the mtDNA genes that, ideally, are specific for the studied taxa. But as such values are often unavailable many studies fixed rate values generalised from other studies, such as the popular "standard molecular clock". However the validity of these universal rates across all bird lineages and for the different mtDNA has been severely questioned. Thus, we here performed the most comprehensive calibration of the mtDNA molecular clock in birds, with the inclusion of complete mitochondrial genomes for 622 bird species and 25 reliable fossil calibrations. The results show variation in the rates between lineages and especially between markers, contradicting the universality of the standard clock. Moreover, we provide especific rates for every mtDNA marker (except D-loop) in each of the sampled avian orders, which should help improve future estimations of divergence times between bird species or populations.

evolutionary biology