Journal Article
Host propagation permits extreme local adaptation in a social parasite of ants
K. Schönrogge; M. G. Gardner; G. W. Elmes; E. K. V. Napper; D. J. Simcox; J. C. Wardlaw; J. Breen; B. Barr; J. J. Knapp; J. A. Pickett; J. A. Thomas
Ecology Letters · Vol. 9, Issue 9 · pp. 1032-1040 · 2006
Abstract
The Red Data Book hoverfly species Microdon mutabilis is an extreme specialist that parasitises ant societies. The flies are locally adapted to a single host, Formica lemani , more intimately than was thought possible in host–parasite systems. Microdon egg survival plummeted in F. lemani colonies > 3 km away from the natal nest, from c. 96% to 0% to Microdon manipulates the social dynamics of F. lemani by feeding selectively on ant eggs and small larvae, which causes surviving larvae to switch development into queens. Infested colonies rear double the number of new queens, thus propagating the vulnerable local genotype and compensating for damage to the host colonies. The consequences of such extreme host specificity for insect conservation are discussed.