Showing papers by "Edward O. Wilson published in 2011"

The Nature of the Taxon Cycle in the Melanesian ant Fauna

Abstract: Undisturbed ant faunas of islands in the Moluccas-Melanesian arc are for the most part "saturated," that is, approach a size that is correlated closely with the landmass of the island but only weakly with its geographic location (figure 1). In the Ponerinae and Cerapachyinae combined the saturation level can be expressed approximately as F=3A0.6, where F is the number of species in the fauna and A the area of the island in square miles. Interspecific competition, involving some degree of colonial warfare, plays a major role in the determination of the saturation curve. It deploys the distribution of some ant species into mosaic patterns and increases the diversification of local faunas. Perhaps because of the complex nature of the Melanesian fauna, differences between local faunas appear that give the subjective impression of randomness. Despite the action of species exclusion, the size of local faunas occurring within a set sample area increases with the total size of the island (figure 2). Water gaps br...

The Ergonomics of Caste in the Social Insects

Abstract: The analysis of caste ratios and their effect on colony efficiency can be approached by linear programming models. In the formulation offered here, account has been taken of certain general features of organization and behavior peculiar to insect societies; selection was assumed to be at the colony level; and the optimization goal was given as the maximum production of new queens and males by a mature colony whose size has an upper limit characteristic of the species. Even in their elementary form, the linear models here produced some interesting new conclusions, among which are the following: 1. Different kinds of contingencies, for which distinct behavioral responses are evolved (e.g., invasion by enemies, larval hunger, nest fouling), will be met by the colony as a whole in such a way that each kind of contingency causes about the same amount of reduction in average queen production. 2. Castes, including both physical variants and temporal behavioral stages, will tend to be proliferated in evolution un...

The Social Biology of Ants

Abstract: If a capsule statement were required defining the prime significance of ants as research objects, it could be the following: the ants are a world­ dominant taxon (family Formicidae) which have achieved their radiation by means of social modifications. They are unique in the magnitude of this achievement, being only remotely approached by their nearest competitors, the termites. With the ants, of which there are over ten thousand species, we are allowed to witness the employment of social design to solve the most diverse ecological problems ordinarily dealt with by single organisms. It is tempting to speculate (and perhaps impossible to prove) that these insects have employed all, or nearly all, of the social strategies permissible within the limits imposed by the hymenopteran brain and the peculiarities of their colonial system. In any case, the study of their social biology must still be considered in an early stage, notwithstanding an already large literature. In the present coverage, emphasis will be on the past fifteen years, al­ though there has been no hesitation to cite important earlier papers. For those interested, a historical perspective can be gotten by reading the books of Forel (53), Goetsch (58, 59), Richards (131), and Wheeler (185, 187). Only behavior and colonial organization are considered. Even after this restriction is made, certain topics have been omitted. Caste determination has been the subject of recent reviews by Brian (19) and Michener (1 15). Schneirla has summarized the results of his and his co-workers' welI-known studies on New World doryline army ants in several detailed articles (140, 142, 143, 148), which should be consulted in conjunction with two more recent research reports (144, 145) on the genus Neivamyrme:r. Especially useful are two of the reviews (142, 143) which take into account Raignier & Van Boven's treatise (128) on the African dorylines. Wilson (198) has considered early stages of army ant behavior in the primitive subfamily Ponerinae. In the present review, biological information in army ants has been mentioned where it was thought to have general significance. The special topic of fungus growing in the Attini has also been bypassed, in view of Weber's current publications (173, 174, 175), but other aspects of a.ttine biology are covered.

Nowak et al . reply

Abstract: Replying to: P. Abbot et al. , 10.1038/nature09831 (2011) ; J. J. Boomsma et al. , 10.1038/nature09832 (2011) ; J. E. Strassmann et al. , 10.1038/nature09833 (2011) ; R. Ferriere & R. E. Michod , 10.1038/nature09834 (2011) ; E. A. Herre & W. T. Wcislo , 10.1038/nature09835 (2011) Our paper challenges the dominant role of inclusive fitness theory in the study of social evolution1. We show that inclusive fitness theory is not a constructive theory that allows a useful mathematical analysis of evolutionary processes. For studying the evolution of cooperation or eusociality we must instead rely on evolutionary game theory or population genetics. The authors of the five comments2,3,4,5,6 offer the usual defence of inclusive fitness theory, but do not take into account our new results.