In this preliminary biometric study of the calcareous nannofossil species Chiasmolithus expansus, Chiasmolithus oamaruensis, and Chiasmolithus altus from the upper middle Eocene to lower Oligocene of Sites 647 and 748, we document a complete gradation of forms among all three species. Chiasmolithus oamaruensis has significantly higher morphologic variance than the other species. The Chiasmolith...

Microbial processes played a major role in mineral precipitation throughout the Earth’s history. Such processes have been widely discussed for the last few decades with regard to carbonate precipitation. Other than microbial precipitation of carbonates, in natural environments is also of great interest the potential role of microbes in the precipitation of marine barite. Regarding carbonates, o...

T volume includes papers from a conference held at the McDonald Institute for Archaeological Research in 2010. The aim of the conference was to examine the histories of populations on the African continent through the use of a variety of data sets—archaeology, genetics, paleoenvironments, and paleontology—to reach a more nuanced understanding of hominin skeletal and behavioral evolution, how po...

Microfossils present in Quaternary micrites from Serra da Bodoquena, Mato Grosso do Sul State, Brazil, are here described for the first time. The studied taxa are: a) ostracods: Candona sp., Candonopsis sp., Cyclocypris sp., Cypria sp., Cypridopsis sp., Notodromas sp., Ilyocypris sp., Cyprideis sp., Wolburgiopsis cf. chinamuertensis (Musacchio 1970), Darwinula sp. and 5 morphotypes; b) microgas...

Genomes conceal a vast intricate record of their carriers' descent and evolution. To disclose this information, biologists need phylogenetic models that integrate various levels of organization, ranging from nucleotide sequences to ecological interactions. Rates of duplication and horizontal gene transfer, organism trees and ancestral population sizes can all be inferred through statistical mod...

The study of the chondrichthyan fauna from the Angostura, Onzole, Canoa and Jama formations, in the Neogene of Bordón and Manabí basins, Ecuador, reveals the presence of 30 taxa, including the deep water shark yChlamydoselachus landinii sp. nov. The assemblages are dominated by tropical shallow and deep water chondrichthyans, suggesting paleoenvironments associated with a short platform shelf b...