Abstract: Boris Ryabko & Zhanna Reznikova Prof. Dr. Boris Ryabko (contact author), Siberian University of Telecommunication and Informatics, Kirov ul. 82, 630102, Novosibirsk, Russia. E-mail: boris@ryabko.net Prof. Dr. Zhanna Reznikova, Institute for Animal Systematics and Ecology, Siberian Branch, Russian Academy of Sciences, Frunze ul. 11, 630091, Novosibirsk, Russia. E-mail: zhanna@reznikova.net Myrmecol. News 10: 121 After twenty years in the shadow of the binary tree (Reznikova & Ryabko 1986, 1994, 2003, Ryabko & Reznikova 1996, Novgorodova 2006), we can now summarize what the information theory introduced by Shannon (1948a, b) furnishes for explorers of ants' communication. Unlike bees, whose dance language remains the most complex among the animal communication systems decoded to date, ants belong to the overwhelming majority of species with codes so far inaccessible for cracking because of many methodological barriers. We have applied ideas and methods of information theory to study ants' communication systems. The main point of our approach…