GEOGRAPHIC VARIATIONS OF LIFE-HISTORY STRATEGIES IN DROSOPHILA-MELANOGASTER .3. NEW DATA

A crucial assumption of evolutionary theories of aging is that age-spe cific differences of life history traits may have genetic causes. The present study focuses on the existence of such differences between eig ht freshly caught populations of Drosophila melanogaster. A highly sig nificant differentiation of the populations is observed, yet it accoun ts for a relatively small part of the variance. It is also shown that large discrepancies may be found between the estimations of fitness ba sed, on the one hand, on data for egg production and, on the other han d, on fertility data. This stresses the need for accurate measurements of fitness for the assessment of evolutionary theories. Finally, the results suggest that neither of the current evolutionary theories of a ging is generally valid. Indeed, the age-specific differences that are found between the populations match either the antagonistic pleiotrop y mechanism, or the concordant pleiotropy mechanism, or none of them. Copyright (C) 1996 Elsevier Science Inc.