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The rapid mandible strike of a termite soldier

2008; Elsevier BV; Volume: 18; Issue: 22 Linguagem: Inglês

10.1016/j.cub.2008.09.033

1879-0445

Marc A. Seid, Rudolf H. Scheffrahn, Jeremy E. Niven,

Fossil Insects in Amber

Arthropods use a remarkable variety of mechanisms to store energy for rapid ballistic movements [1Burrows M. The mechanics and neural control of the prey capture strike in the mantid shrimps Squilla and Hemisquilla.Z. Vergl. Physiol. 1969; 62: 361-381Crossref Scopus (77) Google Scholar, 2Patek S.N. Caldwell R.L. Extreme impact and cavitation forces of a biological hammer: strike forces of the peacock mantis shrimp Odontodactylus scyllarus.J. Exp. Biol. 2005; 208: 3655-3664Crossref PubMed Scopus (145) Google Scholar, 3Evans M.E.G. The jump of the click beetle (Coleoptera, Elateridae) -energetics and mechanics.J. Zool. Lond. 1973; (169,181–194)Google Scholar, 4Bennet-Clark H.C. The energetics of the jump of the locust, Schistocerca gregaria.J. Exp. Biol. 1975; 63: 53-83PubMed Google Scholar, 5Burrows M. Biomechanics: Froghopper insects leap to new heights.Nature. 2003; 424: 509Crossref PubMed Scopus (168) Google Scholar, 6Gronenberg W. Tautz J. Hölldobler B. Fast trap jaws and giant neurons in the ant Odontomachus.Science. 1993; 262: 561-563Crossref PubMed Scopus (62) Google Scholar, 7Patek S.N. Baio J.E. Fisher B.L. Suarez A.V. Multifunctionality and mechanical origins: Ballistic jaw propulsion in trap-jaw ants.Proc. Natl. Acad. Sci. USA. 2006; 103: 12787-12792Crossref PubMed Scopus (115) Google Scholar, 8Gronenberg W. Hölldobler B. Alpert G.D. Jaws that snap: control of mandible movments in the ant Mystrium.J. Insect Physiol. 1998; 44: 241-253Crossref PubMed Scopus (28) Google Scholar]. These movements are primarily either for prey capture [1Burrows M. The mechanics and neural control of the prey capture strike in the mantid shrimps Squilla and Hemisquilla.Z. Vergl. Physiol. 1969; 62: 361-381Crossref Scopus (77) Google Scholar, 2Patek S.N. Caldwell R.L. Extreme impact and cavitation forces of a biological hammer: strike forces of the peacock mantis shrimp Odontodactylus scyllarus.J. Exp. Biol. 2005; 208: 3655-3664Crossref PubMed Scopus (145) Google Scholar] or for predator evasion [3Evans M.E.G. The jump of the click beetle (Coleoptera, Elateridae) -energetics and mechanics.J. Zool. Lond. 1973; (169,181–194)Google Scholar, 4Bennet-Clark H.C. The energetics of the jump of the locust, Schistocerca gregaria.J. Exp. Biol. 1975; 63: 53-83PubMed Google Scholar, 5Burrows M. Biomechanics: Froghopper insects leap to new heights.Nature. 2003; 424: 509Crossref PubMed Scopus (168) Google Scholar], although the mandible strike of the trap-jaw ant can produce both outcomes [6Gronenberg W. Tautz J. Hölldobler B. Fast trap jaws and giant neurons in the ant Odontomachus.Science. 1993; 262: 561-563Crossref PubMed Scopus (62) Google Scholar, 7Patek S.N. Baio J.E. Fisher B.L. Suarez A.V. Multifunctionality and mechanical origins: Ballistic jaw propulsion in trap-jaw ants.Proc. Natl. Acad. Sci. USA. 2006; 103: 12787-12792Crossref PubMed Scopus (115) Google Scholar]. Soldiers of the termite Termes panamaensis (Snyder) also have a mandible strike [9Deligne J. Quennedy A. Blum M.S. The enemies and defense mechanisms of termites.in: Hermann H.R. Social Insects Vol. II. Academic Press, New York1982Google Scholar]. We report that this mandible strike is a rapid, ballistic movement that functions neither for prey capture nor for predator evasion, but as a defence for the colony against insect invaders such as ants or other termite species. Unlike that of the trap-jaw ants [6Gronenberg W. Tautz J. Hölldobler B. Fast trap jaws and giant neurons in the ant Odontomachus.Science. 1993; 262: 561-563Crossref PubMed Scopus (62) Google Scholar, 7Patek S.N. Baio J.E. Fisher B.L. Suarez A.V. Multifunctionality and mechanical origins: Ballistic jaw propulsion in trap-jaw ants.Proc. Natl. Acad. Sci. USA. 2006; 103: 12787-12792Crossref PubMed Scopus (115) Google Scholar], the mandible strike of T. panamaensis soldiers involves a scissor-like movement of highly elongated mandibles across one another, powered by energy stored in deformation of the mandibles, a mechanism convergent with the mandible strike of the ant Mystrium [8Gronenberg W. Hölldobler B. Alpert G.D. Jaws that snap: control of mandible movments in the ant Mystrium.J. Insect Physiol. 1998; 44: 241-253Crossref PubMed Scopus (28) Google Scholar, 10Moffett M. Mandibles that snap: notes on the ant Mystrium camillae Emery.Biotropica. 1986; 18: 361-362Crossref Google Scholar]. The velocity achieved during the T. panamaensis strike exceeds those reported for other ballistic movements in arthropods [1Burrows M. The mechanics and neural control of the prey capture strike in the mantid shrimps Squilla and Hemisquilla.Z. Vergl. Physiol. 1969; 62: 361-381Crossref Scopus (77) Google Scholar, 2Patek S.N. Caldwell R.L. Extreme impact and cavitation forces of a biological hammer: strike forces of the peacock mantis shrimp Odontodactylus scyllarus.J. Exp. Biol. 2005; 208: 3655-3664Crossref PubMed Scopus (145) Google Scholar, 3Evans M.E.G. The jump of the click beetle (Coleoptera, Elateridae) -energetics and mechanics.J. Zool. Lond. 1973; (169,181–194)Google Scholar, 4Bennet-Clark H.C. The energetics of the jump of the locust, Schistocerca gregaria.J. Exp. Biol. 1975; 63: 53-83PubMed Google Scholar, 5Burrows M. Biomechanics: Froghopper insects leap to new heights.Nature. 2003; 424: 509Crossref PubMed Scopus (168) Google Scholar, 6Gronenberg W. Tautz J. Hölldobler B. Fast trap jaws and giant neurons in the ant Odontomachus.Science. 1993; 262: 561-563Crossref PubMed Scopus (62) Google Scholar, 7Patek S.N. Baio J.E. Fisher B.L. Suarez A.V. Multifunctionality and mechanical origins: Ballistic jaw propulsion in trap-jaw ants.Proc. Natl. Acad. Sci. USA. 2006; 103: 12787-12792Crossref PubMed Scopus (115) Google Scholar, 8Gronenberg W. Hölldobler B. Alpert G.D. Jaws that snap: control of mandible movments in the ant Mystrium.J. Insect Physiol. 1998; 44: 241-253Crossref PubMed Scopus (28) Google Scholar] and generates sufficient force upon impact that a single blow can kill invaders within the narrow confines of their tunnels.