Where am I? Where was I going? What was I doing? Memories that guide orb web construction

Orb web construction behavior offers unusual advantages for understanding the mental processes of an arthropod, because an orb weaver's intentions, perceptions, and decisions can be deduced in some contexts by observing the movements of her legs, just as one can make similar deductions from observing how a blind man moves his cane. This study shows that when spiders of two species were experimentally interrupted during orb construction, they remembered for up to several minutes the portion of the web in which they had been working, the type of activity in which they had been engaged, the direction in which they had been moving (left vs right, clockwise vs. counterclockwise), and the location of the hub. Biases in the searching behavior of legs in other contexts revealed apparent expectations regarding the sites and angles of the lines for which the spider was searching. These observations, combined with previous demonstrations of the ability to remember the distance travelled along a radial line, indicate that orb weavers possess the information necessary to form mental representations of their webs. The behavioral phenomena demonstrated here fit Merker's triangular dependency model of animal awareness.