Animals use a variety of signals to communicate with each other, and evolution has resulted in an enormous diversity of species-specific recognition mechanisms. Species recognition is critical, especially in mating, because mistakes can result in loss of reproductive effort, or (in the case of predatory animals) even death. This research concerns the question of how animals recognize members of their own species and discriminate them from other species using visual signals during courtship and mating. A newly developed video imaging technique will be used to understand how visual signals function in the mating process of wolf spiders, and how differences between species evolve. Because spiders are potentially cannibalistic, species recognition mechanisms are critical to survival as well as reproductive success. As a consequence, recognition is innate and based on simple behavioral cues. In the planned experiments, visual signals of courting males (body ornaments and behaviors) will be altered using computer digitization and video animation, then presented to female spiders on microtelevision screens. Responses of females to video images of their own species and those of other species, and combinations of video images with audio recordings of spider courtship vibration "songs", will test hypotheses about the cues involved in species recognition. Results of this research will allow a better understanding of the mechanisms involved in species recognition in animals. This research will also contribute to the growing knowledge about spiders, an ecologically important group of invertebrate predators whose basic biology is less known than other taxa. Additionally, this research involves the continuing development of a computer-assisted technique for studying behavior which may be applicable to other species and research questions in animal behavior (mate choice, agonistic behavior, visual perception, neuroethology) and other fields (image recogn ition, artificial intelligence).
