I am attempting to determine if some of my independent variables have a significant effect on my response variables. In my case, I have various sites in which I determined the quantities of some antibiotic resistance genes (ARGs). So in this case my response variables is the quantities of ARGs and my effects are the river sites and ARG groups.
I have done some ANOVA on the samples and the effect between the two effect variables have been significant. I understand that if this is the case I cannot rely on the significant effect between individual independent variables and the response.
So my question is: Should the interactions between effect variables?