Taphonomy and systematics of Neoproterozoic vase shaped microfossils from Brazil and their paleoecological and phylogenetic significance

• Grant number: 13/12852-1
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2013
• End date: October 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Geosciences
• Principal Investigator: Thomas Rich Fairchild
• Grantee: Luana Pereira Costa de Morais
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 16/05937-9 - Comparative study of vase-shaped microfossils (VSMs) in collections at Harvard University and the University of California at Santa Barbara (Cambridge, MA; Santa Barbara, CA, USA), BE.EP.DR

Abstract

This research will investigate vase-shaped microfossils of two formations of the geological record of Neoproterozoic Brazilian, and compare them with other Neoproterozoic events in the world, with the aim of contributing to the knowledge of paleobiological aspects, related to the evolutionary and biostratigraphic appearance of unicellular eukaryotes within teak in ecosystems prior to the emergence of metazoans. The VSMs were originally assigned to quitinozoários and later amoeboid organisms, including the tintinnídeos, but today are generally related to groups within the arcellinídeos (hierarchical term used here to amoeboid organisms within teak without formal classification). The morphological and compositional range observed in Neoproterozoic VSMs, including the Brazilian specimens, documents the earliest diversification of eukaryotic unicellular life, presumably heterotrophic, preserved in the geological record. The different sedimentary facies containing VSMs provide valuable information on environmental factors that may have been important in this diversification. In addition, wide distribution and variety of these microfossils suggest their possible biostratigraphic application . Petrographic microscopy, Scanning Electron Microscopy, Spectroscopy Energy Dispersive X-ray, Confocal Microscopy and Raman spectroscopy are applied to characterize the composition and morphology that can make inferences about the nature and paleoecology of the organisms responsible for teak. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

LAHR, DANIEL J. G.; KOSAKYAN, ANUSH; LAR, ENRIQUE; MITCHELL, EDWARD A. D.; MORAIS, LUANA; PORFIRIO-SOUSA, ALFREDO L.; RIBEIRO, GIULIA M.; TICE, ALEXANDER K.; PANEK, TOMAS; KANG, SEUNGHO; et al. Phylogenomics and Morphological Reconstruction of Arcellinida Testate Amoebae Highlight Diversity of Microbial Eukaryotes in the Neoproterozoic. Current Biology, v. 29, n. 6, p. 991+, MAR 18 2019. (13/25729-3, 15/02689-1, 13/04585-3, 13/12852-1)

MORAIS, L.; LAHR, D. J. G.; RUDNITZKI, I. D.; FREITAS, B. T.; ROMERO, G. R.; PORTER, S. M.; KNOLL, A. H.; FAIRCHILD, T. R.. Insights into vase-shaped microfossil diversity and Neoproterozoic biostratigraphy in light of recent Brazilian discoveries. JOURNAL OF PALEONTOLOGY, v. 93, n. 4, p. 612-627, JUL 2019. (17/22099-0, 16/05937-9, 13/12852-1)

MORAIS, LUANA; FAIRCHILD, THOMAS RICH; LAHR, DANIEL J. G.; RUDNITZKI, ISAAC D.; SCHOPF, J. WILLIAM; GARCIA, AMANDA K.; KUDRYAVTSEV, ANATOLIY B.; ROMERO, GUILHERME R.. Carbonaceous and siliceous Neoproterozoic vase-shaped microfossils (Urucum Formation, Brazil) and the question of early protistan biomineralization. JOURNAL OF PALEONTOLOGY, v. 91, n. 3, p. 393-406, MAY 2017. (13/04585-3, 13/12852-1)