Figure 2.

R. carbonica Is the First Fossil of an Active Meristem in a Growing Root

(A–C) Cell surface area heat plots show (A) Apex 76.1 (Figure 1A), (B) L. oldhamia [3] (Figure 1B), and (C) R. carbonica (Figure 1C). Scale bars, 200 μm (A and B) and 500 μm (C).

(D) Cell area increase along a single-cell file in Apex 76.1 (blue), L. oldhamia [3] (orange), and R. carbonica (pink). Note the gradual increase in cell size within the ground tissue of R. carbonica compared to Apex 76.1 and L. oldhamia.