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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

The Phanerozoic diversification of silica-cycling testate amoebae and its possible links to changes in terrestrial ecosystems

Texto completo
Lahr, Daniel J. G. [1] ; Bosak, Tanja [2] ; Lara, Enrique [3] ; Mitchell, Edward A. D. [3, 4]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Biosci, Dept Zool, Sao Paulo - Brazil
[2] MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA - USA
[3] Univ Neuchatel, Lab Soil Biol, CH-2000 Neuchatel - Switzerland
[4] Jardin Bot Neuchatel, Neuchatel - Switzerland
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: PeerJ; v. 3, SEP 8 2015.
Citações Web of Science: 15

The terrestrial cycling of Si is thought to have a large influence on the terrestrial and marine primary production, as well as the coupled biogeochemical cycles of Si and C. Biomineralization of silica is widespread among terrestrial eukaryotes such as plants, soil diatoms, freshwater sponges, silicifying flagellates and testate amoebae. Two major groups of testate (shelled) amoebae, arcellinids and euglyphids, produce their own silica particles to construct shells. The two are unrelated phylogenetically and acquired biomineralizing capabilities independently. Hyalosphenids, a group within arcellinids, are predators of euglyphids. We demonstrate that hyalosphenids can construct shells using silica scales mineralized by the euglyphids. Parsimony analyses of the current hyalosphenid phylogeny indicate that the ability to ``steal{''} euglyphid scales is most likely ancestral in hyalosphenids, implying that euglyphids should be older than hyalosphenids. However, exactly when euglyphids arose is uncertain. Current fossil record contains unambiguous euglyphid fossils that are as old as 50 million years, but older fossils are scarce and difficult to interpret. Poor taxon sampling of euglyphids has also prevented the development of molecular clocks. Here, we present a novel molecular clock reconstruction for arcellinids and consider the uncertainties due to various previously used calibration points. The new molecular clock puts the origin of hyalosphenids in the early Carboniferous (similar to 370 mya). Notably, this estimate coincides with the widespread colonization of land by Si-accumulating plants, suggesting possible links between the evolution of Arcellinid testate amoebae and the expansion of terrestrial habitats rich in organic matter and bioavailable Si. (AU)

Processo FAPESP: 13/04585-3 - Decifrando as grandes tendências de evolução molecular e morfológica nos Amoebozoa
Beneficiário:Daniel José Galafasse Lahr
Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores