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  • Silva, Sofia Marques; Townsend Peterson, A.; Carneiro, Lincoln; Tortola Burlamaqui, Tiberio Cesar; Ribas, Camila C.; Sousa-Neves, Tiago; Miranda, Leonardo S.; Fernandes, Alexandre M.; d'Horta, Fernando M.; Araujo-Silva, Lucas Eduardo; Batista, Romina; Bandeira, Cinthia H. M. M.; Dantas, Sidnei M.; Ferreira, Mateus; Martins, Denise M.; Oliveira, Joiciane; Rocha, Taina C.; Sardelli, Carla H.; Thom, Gregory; Rego, Pericles Sena; Santos, Marcos Persio; Sequeira, Fernando; Vallinoto, Marcelo; Aleixo, Alexandre (2019)
    The Amazon is the primary source of Neotropical diversity and a nexus for discussions on processes that drive biotic diversification. Biogeographers have focused on the roles of rivers and Pleistocene climate change in explaining high rates of speciation. We combine phylogeographic and niche-based paleodistributional projections for 23 upland terra firme forest bird lineages from across the Amazon to derive a new model of regional biological diversification. We found that climate-driven refugial dynamics interact with dynamic riverine barriers to produce a dominant pattern: Older lineages in the wetter western and northern parts of the Amazon gave rise to lineages in the drier southern and eastern parts. This climate/drainage basin evolution interaction links landscape dynamics with biotic diversification and explains the east-west diversity gradients across the Amazon.
  • Biersma, E. M.; Jackson, J. A.; Hyvonen, J.; Koskinen, S.; Linse, K.; Griffiths, H.; Convey, P. (2017)
    A bipolar disjunction is an extreme, yet common, biogeographic pattern in non-vascular plants, yet its underlyingmechanisms (vicariance or long-distance dispersal), origin and timing remain poorly understood. Here, combining a large-scale population dataset and multiple dating analyses, we examine the biogeography of four bipolar Polytrichales mosses, common to the Holarctic (temperate and polar Northern Hemisphere regions) and the Antarctic region (Antarctic, sub-Antarctic, southern South America) and other Southern Hemisphere (SH) regions. Our data reveal contrasting patterns, for three species were of Holarctic origin, with subsequent dispersal to the SH, while one, currently a particularly common species in the Holarctic (Polytrichum juniperinum), diversified in the Antarctic region and from here colonized both the Holarctic and other SH regions. Our findings suggest long-distance dispersal as the driver of bipolar disjunctions. We find such inter-hemispheric dispersals are rare, occurring on multi-million-year timescales. High-altitude tropical populations did not act as trans-equatorial 'steppingstones', but rather were derived from later dispersal events. All arrivals to the Antarctic region occurred well before the Last Glacial Maximum and previous glaciations, suggesting that, despite the harsh climate during these past glacial maxima, plants have had a much longer presence in this southern region than previously thought.
  • Murillo Ramos, Leidys Del Carmen; Chazot, Nicolas; Sihvonen, Pasi; Õunap, Erki; Jiang, Nan; Han, Hongxiang; Clarke, John T.; Davis, Robert B.; Tammaru, Toomas; Wahlberg, Niklas (2021)
    Understanding how and why some groups have become more species-rich than others, and how past biogeography may have shaped their current distribution, are questions that evolutionary biologists have long attempted to answer. We investigated diversification patterns and historical biogeography of a hyperdiverse lineage of Lepidoptera, the geometrid moths, by studying its most species-rich tribe Boarmiini, which comprises ca. 200 genera and ca. known 3000 species. We inferred the evolutionary relationships of Boarmiini based on a dataset of 346 taxa, with up to eight genetic markers under a maximum likelihood approach. The monophyly of Boarmiiniis strongly supported. However, the phylogenetic position of many taxa does not agree with current taxonomy, although the monophyly of most major genera within the tribe is supported after minor adjustments. Three genera are synonymized, one new combination is proposed, and four species are placed in incertae sedis within Boarmiini. Our results support the idea of a rapid initial diversification of Boarmiini, which also implies that no major taxonomic subdivisions of the group can currently be proposed. A time-calibrated tree and biogeographical analyses suggest that boarmiines appeared in Laurasia ca. 52 Mya, followed by dispersal events throughout the Australasian, African and Neotropical regions. Most of the transcontinental dispersal events occurred in the Eocene, a period of intense geological activity and rapid climate change. Diversification analyses showed a relatively constant diversification rate for all Boarmiini, except in one clade containing the species-rich genus Cleora. The present work represents a substantial contribution towards understanding the evolutionary origin of Boarmiini moths. Our results, inevitably biased by taxon sampling, highlight the difficulties with working on species-rich groups that have not received much attention outside of Europe. Specifically, poor knowledge of the natural history of geometrids (particularly in tropical clades) limits our ability to identify key innovations underlying the diversification of boarmiines.
  • Santana, Antonita; Silva, Sofia Marques; Batista, Romina; Sampaio, Iracilda; Aleixo, Alexandre (2021)
    The true diversity and interspecific limits in the Neotropical endemic avian genusDendrocolaptes(Furnariidae) remain a highly controversial subject, with previous genus-wide assessments, based mostly on morphological characters, producing poorly resolved phylogenies. The lack of well-resolved, robust, and taxonomically densely sampled phylogenies forDendrocolaptesprevents reliable inferences on the genus' actual species diversity and evolutionary history. Here, we analyzed 2,741 base pairs of mitochondrial and nuclear genes from 43 specimens belonging to all species and the majority of subspecies described forDendrocolaptesto evaluate species limits and reconstruct its diversification through time. Our phylogenies recovered a monophyleticDendrocolaptes, with two main highly supported internal clades corresponding to theD. certhiaandD. picumnusspecies complexes. Also, our analyses supported the monophyly of mostDendrocolaptesspecies recognized today, exceptD. picumnus, which was consistently recovered as paraphyletic with respect toD. hoffmannsi. A coalescent-based test supported a total of 15 different lineages inDendrocolaptesand indicated that the number of currently accepted species within the genus may be greatly underestimated. Particularly relevant, when combined with previous analyses based on plumage characters, comparative high levels of genetic differentiation and coalescent analyses support the recognition ofD. picumnus transfasciatusas a full species that is already under threat. Ancestral area reconstructions suggest that diversification inDendrocolapteswas centered in lowland Amazonia, with several independent dispersal events leading to differentiation into different adjacent dry and high elevation forest types throughout the Neotropics, mainly during the Middle and Late Pleistocene.
  • Poczai, Peter; Hyvönen, Jaakko; Symon, David E. (2011)
  • Rocha, A. V.; Cabanne, G. S.; Aleixo, A.; Silveira, L. F.; Tubaro, P.; Caparroz, R. (2020)
    Based on phylogeographic and niche model analyses of the narrow-billed woodcreeperLepidocolaptes angustirostris, we evaluated the predictions of two diversification hypotheses related to the dry diagonal of South America: (I) isolation by distance (IBD) and (II) landscape heterogeneity. We also investigated the influence of the Pleistocene climatic oscillations on the diversification and population dynamic of this species, and discussed the implications of our findings for the taxonomy of this woodcreeper. We sampled 63 individuals including all subspecies described forL. angustirostris, and compared them using a mitochondrial (ND2) and a nuclear (FIB5) fragments. We performed a Mantel test and spatial autocorrelation analysis, reconstructed the phylogenetic relationships among haplotypes, investigated changes in population size and estimated divergence time among the genetic lineages. We refuted the hypothesis that bird species associated with open environments have shallow geographic differentiation and showed that strong genetic structure observed inL. angustirostriscan not be explained by IBD. Paleo-modeling showed strong association between climatic stable areas and the genetic lineages, suggesting that Pleistocene climatic oscillations have primarily driven the intraspecific diversification of this species. In addition, the association between genetic lineages and the dry diagonal biomes supports that landscape heterogeneity may be acting as a secondary barrier restricting gene flow among the lineages. The genetic lineages found inL. angustirostrisdo not correspond to the subspecies described, indicating that this species can be considered as a single species with strong genetic structure. In conclusion, our data corroborate other studies indicating that Pleistocene climatic oscillations may have had a strong influence in the intraspecific divergence of dry diagonal fauna and that biomes of the dry diagonal should be considered as independent units in further biogeographic studies.