People inside the ark thought outsiders are descendants of humans with some animal mixed in. The ark has a society of scare resources, and the forest that the outsiders have lived in has resources. It seems that there's a "alliance" between the very high ups in both society to keep the current peace for information(outsiders get technology as seen in the school, and insiders probably get forest resources to research the safety for human use). Also I believe that mot revealing that outsiders don't contain any human DNA is a way for the insiders to feel as if they have the highest iq still and are superior beings.
Damnnn thank you for the explanation. That brother rly doesn't like animals ╥﹏╥
I don't g e t i t .
Who's who and what's the problem?? So what if the outsiders aren't humans what's it that has to do with the forest? Σ(っ°Д °;)っ
Too much to function when I'm dying from headache