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1.
Sci Total Environ ; 861: 160534, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36574545

RESUMO

The escape behaviour, measured as flight initiation distance (FID; the distance at which individuals take flight when approached by a potential predator, usually a human in the study systems), is a measure widely used to study fearfulness and risk-taking in animals. Previous studies have shown significant differences in the escape behaviour of birds inhabiting cemeteries and urban parks in European cities, where birds seem to be shyer in the latter. We collected a regional dataset of the FID of birds inhabiting cemeteries and parks across Latin America in peri-urban, suburban and urban parks and cemeteries. FIDs were recorded for eighty-one bird species. Mean species-specific FIDs ranged from 1.9 to 19.7 m for species with at least two observations (fifty-seven species). Using Bayesian regression modelling and controlling for the phylogenetic relatedness of the FID among bird species and city and country, we found that, in contrast to a recent publication from Europe, birds escape earlier in cemeteries than parks in the studied Latin American cities. FIDs were also significantly shorter in urban areas than in peri-urban areas and in areas with higher human density. Our results indicate that some idiosyncratic patterns in animal fearfulness towards humans may emerge among different geographic regions, highlighting difficulties with scaling up and application of regional findings to other ecosystems and world regions. Such differences could be associated with intrinsic differences between the pool of bird species from temperate European and mostly tropical Latin American cities, characterized by different evolutionary histories, but also with differences in the historical process of urbanization.


Assuntos
Cemitérios , Ecossistema , Animais , Humanos , América Latina , Filogenia , Parques Recreativos , Teorema de Bayes , Aves , Cidades , Europa (Continente)
2.
PLoS One ; 12(7): e0180231, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28672032

RESUMO

We evaluated if two sigmodontine rodent taxa (Abrothrix olivacea and Phyllotis darwini) from the Andes and Coastal mountaintops of central Chile, experienced distributional shifts due to altitudinal movements of habitat and climate change during and after the Last Glacial Maximum (LGM). We tested the hypothesis that during LGM populations of both species experienced altitudinal shifts from the Andes to the lowlands and the coastal Cordillera, and then range retractions during interglacial towards higher elevations in the Andes. These distributional shifts may have left remnants populations on the mountaintops. We evaluated the occurrence of intraspecific lineages for each species, to construct distribution models at LGM and at present, as extreme climatic conditions for each lineage. Differences in distribution between extreme climatic conditions were interpreted as post-glacial distributional shifts. Abrothrix olivacea displayed a lineage with shared sequences between both mountain systems, whereas a second lineage was restricted to the Andes. A similar scenario of panmictic unit in the past was recovered for A. olivacea in the Andes, along with an additional unit that included localities from the rest of its distribution. For P. darwini, both lineages recovered were distributed in coastal and Andean mountain ranges at present as well, and structuring analyses for this species recovered coastal and Andean localities as panmictic units in the past. Niche modeling depicted differential postglacial expansions in the recovered lineages. Results suggest that historical events such as LGM triggered the descending of populations to Andean refuge areas (one of the A. olivacea's lineages), to the lowlands, and to the coastal Cordillera. Backward movements of populations after glacial retreats may have left isolates on mountaintops of the coastal Cordillera, suggesting that current species distribution would be the outcome of climate change and habitat reconfiguration after LGM.


Assuntos
Ecossistema , Filogeografia , Roedores/classificação , Animais , Teorema de Bayes , Chile , Genética Populacional , Haplótipos , Funções Verossimilhança , Reação em Cadeia da Polimerase , Roedores/genética
3.
Divers Distrib ; 22(6): 638-650, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27453686

RESUMO

AIM: Biodiversity losses under the species level may have been severely underestimated in future global climate change scenarios. Therefore, it is important to characterize the diversity units at this level, as well as to understand their ecological responses to climatic forcings. We have chosen an endemic rodent from a highly endangered ecogeographic area as a model to look for distributional responses below the species level: Phyllotis darwini. LOCATION: The central Chile biodiversity hotspot: This area harbours a high number of endemic species, and it is known to have experienced vegetational displacements between two mountain systems during and after the Last Glacial Maximum. METHODS: We have characterized cryptic lineages inside P. darwini in a classic phylogeographic approach; those intraspecific lineages were considered as relevant units to construct distribution models at Last Glacial Maximum and at present, as border climatic conditions. Differences in distribution between border conditions for each lineage were interpreted as distributional responses to post-glacial climate change. RESULTS: The species is composed of two major phylogroups: one of them has a broad distribution mainly across the valley but also in mountain ranges, whereas the other displays a disjunct distribution across both mountain ranges and always above 1500 m. The lineage distribution model under LGM climatic conditions suggests that both lineages were co-distributed in the southern portion of P. darwini's current geographic range, mainly at the valley and at the coast. MAIN CONCLUSIONS: Present distribution of lineages in P. darwini is the consequence of a cryptic distributional response to climate change after LGM: postglacial northward colonization, with strict altitudinal segregation of both phylogroups.

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