| molecules versus morphology: the detection of selection acting on morphological characters along a cline in drosophila melanogaster. | this work examines the nature of north-south clinal variation in morphological characters in drosophila melanogaster. isofemale lines were established from flies collected along a transect extending from winnipeg, manitoba (canada) to tampa bay, florida (u.s.a.). offspring from different lines within each location were then cultured under standardized conditions and used to examine phenotypic variation in seven morphological characters along the cline. in addition, allozyme variation at seven po ... | 1995 | 7615402 |