Fig. 3. Lumbar vertebra lengthening exceeds non-specific body growth. (A) The ratio of L4 length to zygomatic arch (ZA) width over time reveals that lumbar growth is occurring at a higher rate than ZA growth (a marker for general growth) in the new queens. Starred dots indicate births. (B) Bar graph plots the percentage change in L4 length and ZA width over the course of the study. The new queens (02-02, 02-04 and 02-05) all have greater increases in L4 length compared with ZA width. The other mole-rats show minimal differences in the percentage change of the two measurements.