Environmental Changes, Coextinction, and Patterns in the Fossil Record

We introduce a new model for large scale evolution and extinction in which species are organized into food webs. The system evolves by two processes: origination/speciation and extinction. In the model, extinction of a given species can be due to an externally induced change in the environment or due to the extinction of all preys of that species (coextinction). The model is able to reproduce the empirical observations without defining a fitness function or invoking competition between species.