is there a way to assign a certain species to certain jobs?

[Damianus]

I bought a bunch of robots with the idea specifically using them as farming bots only to not be able to find any way to make that species only do farming.

[galadon3]

no way to force that, the AI is SUPPOSED to put pops into the jobs they do best and you can see a bit of that if you test around.
For example usually they leave more clerk-jobs free if there are a lot of free jobs and they fill them way more if the race has thrifty (trade from jobs bonus).

That said, it works far from perfect

[Nightmyre]

The closest you can do is by strata - IE, you can have certain species unable to work specialist jobs.

Theoretically, pops should take the jobs they're best suited for, and it does in fact generally work when the pop is created - but it doesn't recalculate at a later stage to switch jobs around. My guess is that's an attempt to cut down on the lag, but it is unfortunate :/