Summary: VOLUME 82, NUMBER 3 P H Y S I C A L R E V I E W L E T T E R S 18 JANUARY 1999
Environmental Changes, Coextinction, and Patterns in the Fossil Record
Lui´s A. Nunes Amaral1
and Martin Meyer2
1
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
2
Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215
(Received 7 August 1998)
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.
[S0031-9007(98)08245-3]
PACS numbers: 87.10.+e, 02.50.Ey, 05.40.­a
The identification of the mechanisms responsible for
large-scale evolution and extinction is a topic of heated
debate [1­8]. The basic problem can be summarized by
two questions. The first one centers on the cause of mass

Source: Amaral, Luis A.N. - Department of Chemical and Biological Engineering, Northwestern University

Collections: Physics; Biology and Medicine