How many skills can my kittens learn?

After researching the technology Civil Servant, you can see that kittens learn and get better at the profession they're working at. Before I knew this (and before I noticed the Census option in the Village) I juggled my kittens around a lot, so they all have two professions and experience levels displayed under their name.

Can they only gain experience in those two professions or are those the two they're most experienced in?

Solution 1:

As per this quote from the developer:

Only two top skills are displayed, but there can be more of them.

The reasoning for only displaying two was also mentioned in that same thread, higher up:

Census will be too overburden on a higher population otherwise.