Predation, in the broad sense of an organism killing another organism for nutritional purposes, is probably as old as life itself and has originated many times during the history of life. Although little of the beginnings is caught in the fossil record, observations in the rock record and theoretical considerations suggest that predation played a crucial role in some of the major transitions in...

Introduction: Geological differences between the ancient and modern Earth show that there was too little O2 in the early atmosphere to leave traces of oxidation that today are common, such as the reddening of exposed iron-rich rocks [1]. The onset of oxidized paleosols, red beds, and the ensuing absence of detrital pyrite, siderite and uraninite all indicate an increase in atmospheric O2 levels...

The Cambrian explosion can be thought of as the culmination of a diversification of eukaryotes that had begun several hundred million years before. Eukaryotes – one of the three domains of life — originated by late Archean time, and probably underwent a long period of stem group evolution during the Paleoproterozoic Era. A suite of taxonomically resolved body fossils and biomarkers, together wi...