Sexual fitness
The number of gonads produced was also significantly influenced by treatment (males: LRT, Gaussian GLMM, λ2 = 56.43, p < 0.001; females: LRT, Negative binomial GLMM with linear parametrization, λ2 = 34.66, p < 0.001). Male polyps exposed to a simulated summer heatwave had reduced number of testes (Table 1.; Fig. 2B.). The negative effects of a warm summer were accentuated if they were followed by cold winter: a sudden large drop in temperature was associated with markedly reduced male fitness (Table 1.; Fig. 2B.). In females, on the other hand, only the WS-CW group had significantly reduced number of eggs compared to the CS-CW group (Table 1., Fig. 3B.).
Surprisingly, polyps exposed to a warm winter treatment underwent a second round of gametogenesis after the first one. This second gametogenesis event happened in individuals that recovered from their first gametogenesis event, around 3-4 months after cooling (Fig. 2C., 3C.).