Stratigraphy is the science that studies the strata, or beds, of (mainly) sedimentary rocks in order to extract from them the history of the earth’s surface. By grouping the bed successions in stratigraphic units and by studying their geometrical relationships with some simple rules, it creates the fundamental temporal relative framework necessary to understand the origin of the rock units them...

Simple stochastic models for phylogenetic trees on species have been well studied. But much paleontology data concerns time series or trees on higher-order taxa, and any broad picture of relationships between extant groups requires use of higher-order taxa. A coherent model for trees on (say) genera should involve both a species-level model and a model for the classification scheme by which spe...

The genetic origin of advanced social organization has long been one of the outstanding problems of evolutionary biology. Here we present an analysis of the major steps in ant evolution, based for the first time, to our knowledge, on combined recent advances in paleontology, phylogeny, and the study of contemporary life histories. We provide evidence of the causal forces of natural selection sh...

For nearly a century the fields of mammalogy and paleomammalogy have complemented each other, although the relative influence of one on the other has waxed and waned. The development of new techniques, databases, and information-handling capabilities in the past decades have enhanced the potential for working at the interface between these 2 fields in ways never before possible. This portends a...

In this work we introduce a general class of spatially heterogeneous competing species models where the species are assumed to disperse in a random way through the inhabiting region in the presence of some refuge patches where they are free from the aggressions of the antagonist species. Our model shows that the competitive exclusion principle fails to be true under these circumstances, as the ...

Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, P.O. Box 37012, Washington, DC, 20013-7013, USA Departments of Mammalogy and Paleontology, Burke Museum of Natural History and Culture, Seattle, WA 98195, USA Cascadia Research Collective, 2181⁄2 West 4th Avenue, Olympia, WA, USA Department of Zoology, University of British Columbia, 6270 University Bouleva...

It is usually assumed that modern language is a recent phenomenon, coinciding with the emergence of modern humans themselves. Many assume as well that this is the result of a single, sudden mutation giving rise to the full "modern package." However, we argue here that recognizably modern language is likely an ancient feature of our genus pre-dating at least the common ancestor of modern humans ...

Eukaryogenesis, the origin of the eukaryotic cell, represents one of the fundamental evolutionary transitions in the history of life on earth. This event, which is estimated to have occurred over one billion years ago, remains rather poorly understood. While some well-validated examples of fossil microbial eukaryotes for this time frame have been described, these can provide only basic morpholo...

In paleontology, we know that in each area, the age of a fossil monotonically increases with depth. We have several observations of age and depth – both known with interval uncertainty – and we would like to find, for each possible depth, the interval of the possible values of the corresponding age. A similar problem of bounding an intervally defined function under monotonicity constraint occur...

Université d’Angers, CNRS UMR6112 LPGN-BIAF – Laboratoire des Bi -Indicateurs Actuels et Fossiles, 2 Boulevard Lavoisier, 49045 Angers Cedex, France University of Vienna, Department of Paleontology, Althanstrasse 14, 1090, Vienna, Austria University of Vienna, Department of Limnology and Oceanography, Althanstrasse 14, 1090, Vienna, Austria Aarhus University, Center for Geomicrobiology, Departm...