Escape Strategies of the Madagascar Hissing Cockroach (Gromphadorhina portentosa) in Response to Looming and Localized Heat Stimuli

摘要

Cockroaches can defend themselves from threats by escape behavior. Although wind-evoked turning in Periplaneta americana is robust, little is known about the turning and translational components of the escape response to looming and localized heat stimuli, especially in other cockroach species. In particular, it has been suggested that the Madagascar hissing cockroach (Gromphadorhina portentosa) lacks an escape response. Our goal was to use high-speed video to explore both the turning and translational components of the escape response of Madagascar cockroaches to looming and heat stimuli. Our results demonstrate that, in contrast to expectations based on previous studies, Madagascar cockroaches do show an escape response that was adapted to looming direction and heat location. Although the escape response to looming stimuli was limited, the response to heat stimulation of their tarsi was unexpectedly robust, especially in translation. The translational responses to both looming and heat were directionally similar (160(o) and 166(o)). Our results demonstrate that G. portentosa also exhibits a well-organized escape response and emphasize the need to quantify both turning and translation to obtain a more complete description of an animals' escape movement.