Scatterplots of hybridization intensities from RNA from somatic tissue from XX;AA and X;AA C. elegans and mouse. Hybridization intensities of (a) germlineless (glp4) XX;AA hermaphrodites plotted against a population greatly enriched for germlineless X;AA male C. elegans (glp4 him5), and (b) female mouse hypothalamus tissue plotted against matched tissue from males. X chromosome (red) and autosomal (black) elements as well as the trend line (red) for the twofold expression difference expected in the absence of dosage compensation are shown. (c-f) Average hybridization intensities corresponding to genes on the X chromosome (red) and autosomes (black) in (c) X;AA glp4 him5 C. elegans male soma and (d) X;AA mouse male soma (average of hypothalamus, kidney and liver) samples, (e) XX;AA glp4 C. elegans hermaphrodite soma, and (f) XX;AA mouse female soma samples. The intensities from individual autosomal arms are averaged across all experiments and standard deviations of the means are indicated.