Periodicity of extinctions in the geologic past.

The temporal spacing and the magnitude of major extinctions over the past 250 and 570 million years, based on the use of different metrics of extinction probability, are analyzed by comparing deterministic and stochastic explanations. The…

The degradation of a periodic signal by dating errors is studied with a view to claims of a highly significant 25-30 million-year period in major extinction events and large craters. The Monte Carlo simulations used placed eight events at equal time…

Structure in the geologic time scale reflects a partly paleontological origin. As a result, ages of Cenozoic and Mesozoic stage boundaries exhibit a weak 28-Myr periodicity that is similar to the strong 26-Myr periodicity detected in mass…

The extinction events at the Cambrian-Ordovician and Ordovician-Silurian boundaries are compared and contrasted. A simple theoretical model shows that times of increased cladogenesis produce elevated rates of taxonomic pseudoextinctions, according…

The extinction events at the Cambrian-Ordovician and Ordovician-Silurian boundaries are compared and contrasted. A simple theoretical model shows that times of increased cladogenesis produce elevated rates of taxonomic pseudoextinctions, according…

EXTINCTION Local extinctions are recurrent events in classic , such as the Melitaea cinxia in Finland.

The protection and recovery of sea otters Enhydra lutris has provided evidence of the consequences of their local extinction from kelp forest communities in the N Pacific Ocean. These consequences include release of benthic invertebrate populations…

Evolutionary histories of species and lineages can influence their vulnerabilities to extinction, but the importance of this effect remains poorly explored for extinctions in the geologic past. When analyzed using a standardized taxonomy within a…

Environmental synergisms may pose the greatest threat to tropical biodiversity. Using recently updated data sets from the International Union for Conservation of Nature (IUCN) Red List, we evaluated the incidence of perceived threats to all known…

Late Pleistocene extinctions are of interest to paleontological and anthropological research. In North America and Australia, human occupation occurred during a short period of time and overexploitation may have led to the extinction of mammalian…