Do the same DoTs / Debuffs stack on one target?

I know that different levels of DoTs/Debuffs DO stack (Bio + Bio II).

However - what if an Arcanist and a Scholar are both casting Bio on the same target. Does the damage stack? Or does one override the other, making one casting redundant.

I've received mixed advice from party members in-game. Some claim they do stack (as the icon is displayed twice) and others claim that they don't.

Anyone know for sure? Can't seem to find this info anywhere online either, oddly enough.

DoTs stack. Debuffs do not. So, you can stack Bio, but not Slow.

The dots DO stack. You will see different icons of the same dot, but each tick won't take damage separatedly. Each dot skill has a single damage tick frame, but that damage tick has both dots (in case there are 2 Bios on the target for example) damage added.