Photoresponse and associative learning inLuidia clathratasay (Echinodermata: Asteroidea)

Abstract

The starfish Luidia clathrata Say demonstrated a negative photoresponse and an ability to associate darkness with a food stimulus (the bivalve, Donax variabilis Say). Individuals exposed to continual light and fed at the beginning of a 15 min period of darkness every 24 h for a period of 10, 20, and 30 days, developed an association between darkness and food. This association was characterized by significantly increased levels of emergence of buried individuals during dark periods. Following the 30‐day conditioning period, individuals continued to exhibit this activity response to darkness for 72 h. The ability to learn to associate darkness with food may be related to increased infaunal prey availability at dusk.