title: A note on the natural basis of action categories: the catching distance of mantids.
abstract: What is the basis for the categorical distinctions evident in action? For some visually-guided activities it can be shown that categories of action are specified by criterial values of optical properties. In the more general case, the criterial optical properties should be scaled relative to dimensions of the acting animal. The analysis of the prey-catching behavior of praying mantids is used to exemplify the strategy for determining naturally defined boundaries on actions.
authors.affiliation: Lake Forest College.
authors.forename: C F
authors.initials: CF
authors.lastname: Michaels
authors.forename: S
authors.initials: S
authors.lastname: Prindle
authors.forename: M T
authors.initials: MT
authors.lastname: Turvey