Can fluctuating asymmetry be used to detect inbreeding and loss of geneticdiversity in endangered populations?

Fluctuating asymmetry (FA), a measure of developmental stability, has been proposed as a simple technique for identifying populations suffering from i nbreeding and a loss of genetic diversity. However, there is controversy re garding the relationship between FA and both allozyme heterozygosity and pe digree inbreeding coefficients (F). FA of sternopleural bristle number in D rosophila melanogaster was measured in populations maintained at effective sizes of 25 (8 replicates), 50 (6), 100 (4), 250 (3) and 500 (2) for 50 gen erations (inbreeding coefficients of 0.05-0.71). FA was calculated from the same data set using three different indices (FA(1), FA(5) and FA(6)). Ther e was no significant relationship of FA with pedigree inbreeding coefficien ts for any of the three indices. The relationship between FA and allozyme h eterozygosity was non-significant for indices FA(5) and FA(6) (the more pow erful indices) and only significant for FA(1). A second comparison of highl y inbred (F approximate to 1) populations with their outbred base populatio n showed significantly greater FA in the inbred populations only when analy sed with FA(6). Analysis of the same data using FA(1) and FA(5) showed nons ignificant relationships in the opposite direction. If a relationship betwe en FA and genetic diversity does exist, it is weak and inconsistent. Conseq uently, our results do not support the use of FA as a monitoring tool to de tect inbreeding or loss of genetic diversity.