The Cerrado is a wide Neotropical savanna with tremendously high endemic diversity. Yet, it is not clear what the prevalent processes leading to such diversification are. We used the Cerrado-endemic lizard Norops meridionalis to investigate the main abiotic factors that promoted genetic divergence, the timings of these divergence events, and how these relate to cryptic diversity in the group. We sequenced mitochondrial and nuclear genes from 21 sites of N. meridionalis to generate species tree, divergence time estimations, and estimate species limits. We also performed population-level analysis and estimated distribution models to test the roles of niche conservatism and divergence in the group diversification. We found that N. meridionalis is composed by at least five cryptic species. Divergence time estimations suggest that the deepest branches split back into the early-mid Miocene, when most of the geophysical activity of the Cerrado took place. The deep divergences found in N. meridionalis suggest that beta anoles invaded South America much earlier than previously thought. Recent published evidence supports this view, indicating that the Panama gap closed as early as 15 mya, allowing for an early invasion of Norops into South America. The spatial pattern of diversification within N. meridionalis follows a northwest-southeast direction, which is consistent across several species of vertebrates endemic to the Cerrado. Also, we found evidence for non-stationary isolation by distance, which occurs when genetic differentiation depends on space. Our preliminary data in two out of five lineages suggest that niche conservatism is an important mechanism that promoted geographic fragmentation in the group.
Aim Our aims were to investigate the spatial genetic structure of Micrablepharus atticolus and to assess the relative importance of differentiation in plateaus versus depressions, in areas of historical stability versus instability, and in central versus peripheral regions. Location The Brazilian Cerrado. Methods We compared the elevational range of M. atticolus with that of its sister species, Micrablepharus maximiliani, to investigate their putative elevational segregation. We identified past (6, 21 and 130 ka) and current variables associated with the distribution of M. atticolus. Based on cytochrome b sequences, we compared genetic diversity indexes and neutrality statistics between plateau/depression, stable/unstable and core/periphery populations. We identified geographically homogeneous and maximally differentiated groups of populations and tested the association between genetic and geographical distances. Finally, we traced elevational range on the phylogeny and tested for a significant phylogenetic signal associated with elevation. Results We found no elevational segregation between M. atticolus and M. maximiliani. There is high genetic diversity and structuring among populations, with the primary differentiation occurring between north‐eastern and south‐western Cerrado localities. We recognized three main groups of populations that roughly correspond to the southern, central‐northern and north‐western portions of the Cerrado, which diverged between 3.5 and 1.5 Ma. Genetic diversity indices indicated no differences between plateaus and depressions or stable and unstable areas, but samples from peripheral isolates in south‐western Amazonia exhibited low haplotype and nucleotide diversity and signs of population expansion. Main conclusions The diversification of M. atticolus in the Cerrado was primarily affected by events in the late Neogene. We found no support for the plateau/depression and stability/instability hypotheses, but we did find support for the core/periphery hypothesis. The spatial patterns seemingly resulted from a combination of shifting environmental conditions during climatic cycles, with repeated colonizations of plateaus and depressions, isolation by distance, and divergence in and recolonization of peripheral isolates within Amazonia.
In this paper some preliminary fossil specimens are presented. They represent a collection sampled by Belo Monte's Programa de Salvamento do Patrimônio Paleontológico (PSPP), which includes unprecedented invertebrate fauna and fossil vertebrates from Pitinga, Jatapu, Manacapuru, Maecuru e Alter do Chão formations from Amazonas basin, Brazil. The Belo Monte paleontological salvage was able to recover 495 microfossil samples and 1744 macrofossil samples on 30 months of sampling activities, and it is still ongoing. The macrofossils identified are possible plant remains, ichnofossils, graptolites, brachiopods, molluscs, athropods, Agnatha, palynomorphs (miosphores, acritarchs, algae cysts, fungi spores and unidentified types) and unidentified fossils. However, deep scientific research is not part of the scope of the program, and this collection must be further studied by researchers who visit Museu Paraense Emilio Goeldi, where the fossils will be housed. More material will be collected until the end of the program. The collection sampled allows a mosaic composition with the necessary elements to assign, in later papers, taxonomic features which may lead to accurate species identification and palaeoenvironmental interpretations.Keywords: mitigation paleontology, Silurian, Devonian, cretaceous, South America, Southern Hemisphere. Resultados preliminares do programa de salvamento paleontológico da construção da Hidrelétrica de Belo Monte ResumoNeste artigo são apresentados de forma preliminar alguns espécimes fósseis representativos do acervo coletado no Programa de Salvamento do Patrimônio Paleontológico (PSPP) da UHE Belo Monte, que inclui fauna vertebrada e invertebrada inédita das formações Pitinga, Jatapu, Manacapuru, Maecuru e Alter do Chão, da bacia do Amazonas, Brasil. No salvamento paleontológico de Belo Monte foi possível recuperar 495 amostras para microfósseis e 1744 amostras com macrofósseis em 30 meses de amostragem, que ainda continua em andamento. Os macrofósseis identificados são possíveis restos de plantas, icnofósseis, graptolitos, braquiópodes, moluscos, artópodes, Agnatha, palinomorfos (miósporos, acritarcas, cistos de alga, esporos de fungo e tipos indeterminados) além de fósseis não identificados. No entanto, pesquisa científica aprofundada não é parte do escopo do programa, e esta coleção deve ser estudada no futuro por pesquisadores pela visita ao Museu Paraense Emilio Goeldi, onde os fósseis ficarão depositados. Mais material será coletado até o fim de 2015. A assemblagem coletada permite a composição de mosaico com elementos necessários para a definição, em artigos futuros, características taxonômicas que levarão à identificação precisa de espécies e interpretações paleoambientais.
Nesting in the lizard Phyllopezus pollicaris (Squamata: Phyllodactylidae) and a phylogenetic perspective on communal nesting in the family. Communal nesting occurs in many reptile species. The hypotheses that explain the evolution of such behaviours are still controversial, but will be better understood as more communal nesting records are a communal nesting record for squamate species in a Cerrado core area. We provide nest photographs and detailed neonate measurements and weight. Nests were found during the dry season, in contrast with the reproduction pattern previously described for the species in the Cerrado periphery. We also conducted an extensive literature review seeking all available information on communal nesting information in Phyllodactylidae, and present this information in the context of a phylogenetic tree of phyllodactylid genera. We suggest that studying the correlation between communal nesting evolution and reproductive available in the literature. Keywords
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