Termites (Blattodea: Isoptera) have evolved specialized defensive strategies for colony protection. Alarm communication enables workers to escape threats while soldiers are recruited to the source of disturbance. Here, we study the vibroacoustic and chemical alarm communication in the wood roach Cryptocercus and in 20 termite species including seven of the nine termite families, all life-types, and all feeding and nesting habits. Our multidisciplinary approach shows that vibratory alarm signals represent an ethological synapomorphy of termites and Cryptocercus. In contrast, chemical alarms have evolved independently in several cockroach groups and at least twice in termites. Vibroacoustic alarm signaling patterns are the most complex in Neoisoptera, in which they are often combined with chemical signals. The alarm characters correlate to phylogenetic position, food type and hardness, foraging area size, and nesting habits. Overall, species of Neoisoptera have developed the most sophisticated communication system amongst termites, potentially contributing to their ecological success.

Czech Technical University Prague Faculty of Electrical Engineering 166 27 Prague 6 Czech Republic

Division of Entomology Natural History Museum and Department of Ecology and Evolutionary Biology 1501 Crestline Drive Suite 140 University of Kansas Lawrence Kansas 66045 USA

Entomology and Nematology Department Fort Lauderdale Research and Education Center University of Florida Institute of Food and Agricultural Sciences Fort Lauderdale Florida 33314 USA

Faculty of Environmental Sciences Czech University of Life Sciences Prague 165 21 Prague 6 Suchdol Czech Republic

Faculty of Forestry and Wood Sciences Czech University of Life Sciences Prague 165 21 Prague 6 Suchdol Czech Republic

Faculty of Tropical AgriSciences Czech University of Life Sciences Prague 165 21 Prague 6 Suchdol Czech Republic

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences 166 10 Prague Czech Republic

Okinawa Institute of Science and Technology Graduate University Okinawa Japan

University Sorbonne Paris Nord Laboratory of Experimental and Comparative Ethology UR4443 93430 Villetaneuse France

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