Fig. 2.

Fig. 2.

Two-stain pulse-chase method for assessing tooth turnover. (A-A″) Example images of the pulse-chase method on a control stickleback. (A) Alizarin Red strongly marks all bone undergoing active ossification at the start of the treatment (magenta). (A′) 18 days later, after 36 heat shocks, a calcein chase marks all bone ossifying at the end of the treatment (green). (A″) An overlay of Alizarin Red and calcein reveals whether individual teeth were either present at only the second labeling (new; calcein only, example labeled ‘n’) or present at both the first and second labeling (retained; Alizarin Red and calcein positive, example labeled ‘r’). (B) An example overlay of the pulse-chase treatment on zebrafish teeth using the same treatment interval. Scale bars: 25 μm.