Fig. 1.—

Strata identified using previously assayed X-linked genes. Here we apply the segmentation and clustering algorithm to a concatenated string of the X-linked genes that have been previously assayed using inversion, phylogenetic, and substitution rate analyses. Previous strata are colored: 5, Red; 4, Yellow; 3, Geen; 2, Blue; 1, Violet. Genes in each cluster are labeled above the cluster, similarly color-coded. Genes that span cluster boundaries are marked with a star. We used Markov model of order 2 to perform segmentation and clustering at significance thresholds of 0.3 and 0.04, respectively.