Phylogenetic tree and TE dynamics across reptilian lineages.

From inner to outer rings: (1) The bubble plot illustrates genome size variation, where larger and darker-colored bubbles indicate greater genome sizes. (2) Stacked bar chart delineates repetitive sequence and TE proportions. (3) Secondary stacked bar chart breaks down TE class composition. (4) Tertiary stacked bar chart specifies TE class distribution among recent insertions (divergence ≤ 5%). SINEs, LINEs, LTRs, and DNA transposons are classified as major TE classes.

A Simpson’s Paradox in sauropsid TE evolution.

(a) Cross-clade scatter plot of log10-transformed body mass versus TE proportion for all 167 sauropsids, colored by clade. The pooled Pearson correlation is positive (r = 0.213). (b) Results of the segmented structural equation model. Fisher’s C = 2.715, p = 0.607; Chi-squared = 1.158, p = 0.56. The black solid line represents a positive correlation, the red solid line represents a negative correlation, the gray line represents no correlation, and the thickness of the line represents the degree of correlation. TE proportion and dN/dS jointly explain 54% of the variation in genome size (R² = 0.54). Weight explains 31% of the variation in generation time (R² = 0.31). The explanatory degree of dN/dS is (R² = 0.05), and the explanatory degree of TE proportion is (R² = 0.01). (c) Forest plot presenting the results of person-related correlation analyses of body mass and TE proportion in each group. (d) Forest plot presenting the results of person-related correlation analyses of generation time and TE proportion in each group. (e) Forest plot presenting the results of person-related correlation analyses of dN/dS and TE proportion in each group.

Structural equation model results.

Overall goodness-of-fit: Fisher’s C = 2.715 (p = 0.607), Chi-squared = 1.158 (p = 0.56), meeting the goodness-of-fit criterion (p > 0.05). The model explained 54% of the variance in genome size, 31% of the variance in generation time, and smaller amounts of variance: 5% for dN/dS and 1% for TE proportion. All coefficients have been phylogenetically corrected. Significance codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05.