QTL analysis of dauer larva formation and population size. LOD scores for chromosomes I, II, III and X for QTL mapping of (A) dauer larva formation in response to high (—) and low (- - -) food concentrations and the plasticity of dauer larva formation (· · ·) and the respective genome-wide LOD significance thresholds for these traits, some of which are co-incident, shown as horizontal lines and (B) the population size on days 5 (—), 7 (- - -) and 9 (· · ·) and the respective genome-wide LOD significance thresholds for these traits, shown as horizontal lines. For each chromosome, the genetic distance between the outermost markers and their physical location is given . Note that in (A), the LOD scale differs for the X chromosome. Positions of the markers described in Table 2 are shown by ◆.