Figure 4.

Calcium spike rate of tCB neurons does not depend on Hydra's body size and number of neurons, see also Figure S3

(A) Number of neurons as a function of animal size (N = 4 per diet condition).

(B) Fluorescence images of Hydra at days 1 and 15 for both control and food-deprived groups (pseudo colored). Scale bar, 200 μm.

(C) Change in the number of neurons over the time course of 15 days. Curve corresponds to the mean, and shaded region corresponds to standard deviation.

(D) Estimated number of neurons from measurements in (A). Data represented as mean ± standard error of the mean.

(E) Three representative Hydra from small and large groups (pseudo colored). Scale bar, 1 mm.

(F) Calcium spike rates from large (N = 3 per size at each temperature) and small (N = 3 per size at each temperature) Hydra, all cultured at 18°C. (ns = not significant, ∗∗∗p < 0.00001, Mann-Whitney U test. δ = Effect size using Cliff's delta). Box-and-whisker plots indicate Q1, median, and Q3; whisker lengths indicate the 2^nd and 98^th percentiles.