In this post, it was discussed on using da before the actual fact with a comma. I came across a slight variant of it recently:
Es gibt auch ~~manche~~ Forschung als beweis dafuer. (me)
Es gibt auch Forschung dazu als Beweis dafuer. (corrected)
I understand why the "manche" is dropped; Forschung is something which is not quantifiable in the linguistic sense. However, why is the "dazu" inserted? Could someone explain?