Figure 1. Larvae alter the length of their post-oral arms in response to food.
DIC images of larvae at the end of the pre-feeding period, day 5, cultured without (a) and with (b) algae starting at gastrula stage. The lengths of the post-oral and body rod skeletal elements are indicated by the black lines. Quantification of (c) post-oral arm length, representing a 20.2% (± 3.9 SEM) change, and (d) body rod length, representing a 3.9% (± 1.5 SEM) change for larvae cultured with (green, n = 20) and without (blue, n = 18) algae. Student's two-tailed t-test, *** P < 0.001. Error bars ± SEM. PO, post-oral arm; BR, body rod. Scale bars, 50 μm.