two way anova in excel with multiple comparison

When using type III anova in R, be sure to change the type of contrasts used in the model. Have you checked residuals for homoscedasticity? You might look in to using tests that are robust to heteroscedasticity, just as white.adjust in car:Anova. I'm also surprised you don't see a significant interaction effect, but I suspect that has to do with the high variability in the data for age 5. It's best to keep everything in one model, as you have done. Is a two way Anova the appropriate test to understand when in development visual experience has an effect? or would it be more appropriate to test between rearing conditions at each developmental age and within rearing condition at each age and correct for the multiple comparisons using a bonferroni correction since i am not interested in the comparisons between groups at different ages. Could some please explain why I am seeing no effect? Is it due to the variance at 5 dpf being larger than at 3 or 7?

Since I have 2 independent variables (Age and Rearing condition) I conducted a two-way Anova (type III SS - due to unbalanced groups) in R but i find no interaction between Rearing condition and Age despite there being appearing to be a difference between Rearing condition at 7 dpf (see plot). One thing I am interested in knowing is when in development visual experience has an effect. I am currently conducting an experiment looking at the effect of visual experience on the development of neural network firing freq.

Two way anova in excel with multiple comparison