Adventures Among Ants - Mark W. Moffett [166]
17. J Bequaert 1922, Predaceous enemies of ants, Bull. Am. Mus. Nat. Hist. 45: 271–331.
6. Big Game Hunters
1. Driver ants are classified as the surface-active, swarm-raiding army ant species in Anomma, a subgenus within the genus Dorylus.
2. Ogden Nash, Ogden Nash’s Zoo (New York: Stewart, Tabori & Chang, 1986), p. 41.
3. Y Möbius, C Boesch, K Koops, T Matsucawa, T Humle 2008, Cultural differences in army ant predation by West African chimpanzees? A comparative study of microecological variables, Anim. Behav. 76: 37–45; C Schöning, T Humle, Y Möbius, WC McGrew 2008, The nature of culture: Technological variation in chimpanzee predation on army ants revisited, J. Hum. Evol. 20: 48–59.
4. WH Gotwald Jr. 1984, Death on the march: Army ants in action, Rotunda 17: 37–41.
5. EO Wilson, NI Durlach, LM Roth 1958, Chemical releasers of necrophoric behavior in ants, Psyche 65: 108–114.
6. The segregation of tasks based on size, as occurs in more labor-intensive road-construction activities in the marauder ant, is less evident in driver ants: Caspar Schöning, personal communication; C Schöning, W Kinuthia, NR Franks 2005, Evolution of allometries in the worker caste of Dorylus army ants, Oikos 110: 231–240.
7. Marauders bring in little food during dry spells; however, they cut back foraging accordingly, with few and weaker raids. Driver ant raids are more richly rewarded after rains, when insect abundance skyrockets. But as I later saw for myself on a trip to rainy Ghana, even then escapees are common. In the fifty or so raids I eventually observed of seven driver ant species in Nigeria and Ghana, less than one in a hundred ants, and often more like one in a thousand, returned with food in her jaws, compared to 10 to 40 percent of marauder ants. It may be that some populations are more efficient; according to one report (A Raignier, J van Boven, Étude taxonomique, biologique et biométrique des Dorylus du sous-genre Anomma, Annales du Musée Royal du Congo Belge, n.s. 4, Sciences Zoologiques, vol. 2 [1955]: 1–359), from 7 to 22 percent of Dorylus wilverthi workers carry back food, though Caspar Schöning tells me this estimate seems high.
8. EO Wilson 1958, The beginnings of nomadic and group-predatory behavior in the ponerine ants, Evolution 12: 24–36.
9. This runs contrary to expectations that larger colonies show a steadier food intake and most likely occurs, I believe, because of the nonindependence of raiding ants during mass foraging, which makes an army ant colony the equivalent of a single large animal; see JW Wenzel, J Pickering 1991, Cooperative foraging, productivity, and the central limit theorem, Proc. Natl. Acad. Sci. 88: 36–38.
10. This idea is pursued in WH Gotwald Jr. 1974, Predatory behavior and food preferences of driver ants in selected African habitats. Ann. Entomol. Soc. Am. 67: 877–886.
11. These are not members of the replete caste, just well-fed ordinary workers.
12. Overlapping ideas are discussed for leafcutter ants in J Röschard, F Roces 2003, Cutters, carriers, and transport chains: Distance-dependent foraging strategies in the grass-cutting ant Atta vollenweideri, Insectes Soc. 50: 237–244; JJ Howard 2001, Costs of trail construction and maintenance in the leaf-cutting ant Atta columbica, Behav. Ecol. Sociobiol. 49: 348–356; and F Roces, JA Núñez 1993, Information about food quality influences load-size selection in recruited leaf-cutting ants, Anim. Behav. 45: 135–143.
13. LMA Bettencourt, J Lobo, D Helbing, C Kühnert, GB West 2007, Growth, innovation, scaling, and the pace of life in cities, Proc. Natl. Acad. Sci. 104: 7301–7306.
14. Deborah M. Gordon, Ants at Work: How an Insect Society Is Organized (New York: Free Press, 1999). To study another instance of apparent “counting,” researchers chopped an ant’s legs short or lengthened them with straw to demonstrate that distance traveled was measured by an internal odometer; see M Wittlinger, R Wehner, H Wolf 2006, The ant odometer: Stepping on stilts and stumps, Science 312: 1965–1967.
15. Scott Camazine, Jean-Louis