Laboratory selection experiments using Drosophila: what do they really tell us?

Laboratory selection experiments using Drosophila, and other organisms, are widely used in experimental biology. In particular, such experiments on D. melanogaster life history and stress-related traits have been instrumental in developing the emerging field of experimental evolution. However, simil ar selection experiments often produce inconsistent correlated responses to selection. Unfortunately, selection experiments are vulnerable to artifact s that are difficult to control. In spite of these problems, selection expe riments are a valuable research tool and can contribute to our understandin g of evolution in natural populations.