Evidence of artefacts made of giant sloth bones in central Brazil around the last glacial maximum.

The peopling of the Americas and human interaction with the Pleistocene megafauna in South America remain hotly debated. The Santa Elina rock shelter in Central Brazil shows evidence of successive human settlements from around the last glacial maximum (LGM) to the Early Holocene. Two Pleistocene archaeological layers include rich lithic industry associated with remains of the extinct giant ground sloth .

The role of volcanic-derived clays in the preservation of Ediacaran biota from the Itajaí Basin (ca. 563 Ma, Brazil).

The early evolution of metazoans has been reconstructed by studies on exceptionally preserved molds in siliciclastic rocks from the Ediacaran Period. However, there remains considerable controversy regarding the formation mechanisms of this unusual 'Ediacaran-style' preservation. Proposed hypotheses usually include early authigenesis of minerals, but evidence for this is scarce.

Ichnological evidence for meiofaunal bilaterians from the terminal Ediacaran and earliest Cambrian of Brazil.

The evolutionary events during the Ediacaran-Cambrian transition (~541 Myr ago) are unparalleled in Earth history. The fossil record suggests that most extant animal phyla appeared in a geologically brief interval, with the oldest unequivocal bilaterian body fossils found in the Early Cambrian. Molecular clocks and biomarkers provide independent estimates for the timing of animal origins, and both suggest a cryptic Neoproterozoic history for Metazoa that extends considerably beyond the Cambrian fossil record.

Ecological interactions in Cloudina from the Ediacaran of Brazil: implications for the rise of animal biomineralization.

At the Ediacaran/Cambrian boundary, ecosystems witnessed an unparalleled biological innovation: the appearance of shelled animals. Here, we report new paleoecological and paleobiological data on Cloudina, which was one of the most abundant shelled animals at the end of the Ediacaran. We report the close association of Cloudina tubes with microbial mat textures as well as organic-rich material, syndepositional calcite and goethite cement between their flanges, thus reinforcing the awareness of metazoan/microorganism interactions at the end of the Ediacaran.

Deciphering the preservation of fossil insects: a case study from the Crato Member, Early Cretaceous of Brazil.

Exceptionally well-preserved three-dimensional insects with fine details and even labile tissues are ubiquitous in the Crato Member Konservat Lagerstätte (northeastern Brazil). Here we investigate the preservational pathways which yielded such specimens. We employed high resolution techniques (EDXRF, SR-SXS, SEM, EDS, micro Raman, and PIXE) to understand their fossilisation on mineralogical and geochemical grounds.

Absorption and Phase Contrast X-Ray Imaging in Paleontology Using Laboratory and Synchrotron Sources.

X-ray micro-computed tomography (μCT) is commonly used for imaging of samples in biomedical or materials science research. Owing to the ability to visualize a sample in a nondestructive way, X-ray μCT is perfectly suited to inspect fossilized specimens, which are mostly unique or rare. In certain regions of the world where important sedimentation events occurred in the Precambrian geological time, several fossilized animals are studied to understand questions related to their origin, environment, and life evolution.

Insights into the skeletonization, lifestyle, and affinity of the unusual Ediacaran fossil Corumbella.

The Ediacaran fossil Corumbella is important because it is hypothesized to be a scyphozoan cnidarian, and thus might be one of the rare examples of bona fide Neoproterozoic animals. Unfortunately, its mode of life, style of skeletonization, and taxonomic affinity have been very controversial. Here, we use X-ray micro-CT, SEM, and taphonomic analysis to compare preservational modes of Corumbella, in order to better understand the symmetry, mode of construction, preservational style, and taxonomy of this group.

From cytoplasm to environment: the inorganic ingredients for the origin of life.

Early in its history, Earth's surface developed from an uninhabitable magma ocean to a place where life could emerge. The first organisms, lacking ion transporters, fixed the composition of their cradle environment in their intracellular fluid. Later, though life adapted and spread, it preserved some qualities of its initial environment within.