Extended Data Fig. 9: Comparison of relative larval TAI contribution between ps4 and other phylostratum levels.

Across eight metazoan species, the larval TAI contribution by the genes of ps4 is significantly larger than those by other phylotratum levels (except ps11), implicating ps4 (Metazoa) as the potential timing of single proto-larva origin. For each phylotratum, the larval TAI contribution was normalized by fold difference relative to the average value across eight metazoan species. The lines inside the box indicate the median values, the whiskers extend from the first or third quartiles to the minimum or maximum values and the dots show individual data points. For comparisons of ps4 with other phylostratum levels, statistical significance based on one-sided t-test is shown on the top of each box.