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Fábia Guimarães-Dias Anna C. Neves-Borges Alessandra J. Conforte Leonardo Giovanella-Kampmann André V. J. Ferreira Regina M. S. Amorim Magda A. Benevent Maria Eugênia Lisei de Sá Rosilene O. Mesquita Fabiana A. Rodrigues Alexandre L. Nepomuceno Eduardo Romano Marcelo E. Loureiro Maria Fátima Grossi-de-Sá Márcio Alves-Ferreira 《Plant Molecular Biology Reporter》2016,34(6):1167-1180
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Physiological responses to extreme hydrological events in the Pantanal wetland: heterogeneity of a plant community containing super‐dominant species
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Phylogenetic distribution of regeneration and asexual reproduction in Annelida: regeneration is ancestral and fission evolves in regenerative clades
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Regeneration, the ability to replace lost body structures, and agametic asexual reproduction, such as fission and budding, are post‐embryonic developmental capabilities widely distributed yet highly variable across animals. Regeneration capabilities vary dramatically both within and across phyla, but the evolution of regeneration ability has rarely been reconstructed in an explicitly phylogenetic context. Agametic reproduction appears strongly associated with high regenerative abilities, and there are also extensive developmental similarities between these two processes, suggesting that the two are evolutionarily related. However, the directionality leading to this relationship remains unclear: while it has been proposed that regeneration precedes asexual reproduction, the reverse hypothesis has also been put forward. Here, we use phylogenetically explicit methods to reconstruct broad patterns of regeneration evolution and formally test these hypotheses about the evolution of fission in the phylum Annelida (segmented worms). We compiled from the literature a large dataset of information on anterior regeneration, posterior regeneration, and fission abilities for 401 species and mapped this information onto a phylogenetic tree based on recent molecular studies. We used Markovian maximum likelihood and Bayesian MCMC methods to evaluate different models for the evolution of regeneration and fission and to estimate the likelihood of each of these traits being present at each node of the tree. Our results strongly support anterior and posterior regeneration ability being present at the basal node of the annelid tree and being lost 18 and 5 times, respectively, but never regained. By contrast, the ability to fission is reconstructed as being absent at the basal node and being gained at least 19 times, with several possible losses. Models assuming independent evolution of regeneration and fission yield significantly lower likelihoods. Our findings suggest that anterior and posterior regeneration are ancestral for Annelida and are consistent with the hypothesis that regenerative ability is required to evolve fission. 相似文献
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Genetic signature of the northward expansion of the Egyptian mongoose Herpestes ichneumon (Herpestidae) in the Iberian Peninsula
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Tânia Barros Eduardo Ferreira Rita Gomes Rocha Philippe Gaubert Victor Bandeira Luis Souto António Mira Carlos Fonseca 《Biological journal of the Linnean Society. Linnean Society of London》2016,118(3):686-697
In the last three decades, the range of the Egyptian mongoose (Herpestes ichneumon) has increased in the Iberian Peninsula. A panel of microsatellites was used to confront the patterns of genetic diversity of the species with the scenario of its recent northward expansion in its Iberian range. Evidence of substructure and significant genetic differentiation within the studied population were recorded, with a central‐northern subpopulation (CNorth) and a southern subpopulation (S). Northward range expansion was supported by the observed allelic frequencies, diversity parameters, and observed heterozygosity of the studied loci, with S showing a higher allelic diversity and a higher number of private alleles than CNorth. Patterns of isolation‐by‐distance and isolation‐by‐barrier as a result of the Tagus River were demonstrated, suggesting that the river acted as a semi‐permeable barrier, possibly leading to genetic differentiation of the studied population. The observed individuals from CNorth in southern locations and individuals from S in central/northern areas might comprise evidence for long‐range dispersals across the studied range. A bottleneck event after population expansion was supported by a significant heterozygosity deficiency in CNorth, which is in agreement with a scenario of founder events occurring in recently colonized areas after the crossing of the Tagus River. 相似文献