That time is both a dimension of behaviour and a ubiquitous controlling variable in the lives of all living things has been well recognized for many years.
The last decade has seen a burgeoning of interest in the quantitative analysis of timing behaviour, and progress during the last five or six years has been particularly impressive, with the publication of several major new theoretical contributions.
There has also been considerable progress in behavioural methodology during the past decade. In the area of reinforcement schedules, for example, the venerable interresponse-time...