title: Tempo and mode of evolution in the tangled nature model.
abstract: The fossil record has been interpreted as exhibiting a gradual decrease in the extinction rate. We use the individual based Tangled Nature model of evolutionary ecology to study the mechanisms behind this kind of nonstationary macrodynamics. We demonstrate that the long time aging in the system (manifested as a slowing down of the rate of large jumps, or quakes, that the system undergoes) is related to decreasing fluctuations in the offspring probability. The scenario is reminiscent of relaxation in a quenched spin glass but purely dynamical in nature since no energy barriers can be defined.
authors.affiliation: Institute of Mathematical Sciences, 53 Princes' Gate, Imperial College London, London SW7 2PG, United Kingdom. dominic.jones@imperial.ac.uk
authors.forename: Dominic
authors.initials: D
authors.lastname: Jones
authors.forename: Henrik Jeldtoft
authors.initials: HJ
authors.lastname: Jensen
authors.forename: Paolo
authors.initials: P
authors.lastname: Sibani