Copyrights question.

I’m considering using an illustration found on Wikipedia as part of my Master thesis. The file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license, meaning this sort of use is okay as long as it’s attributed to the author (whom I can only know by his screen name), the license is mentioned, and “if you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one.”

Main question: Would using this picture as an illustration in the introduction legally necessitate making the entire thesis available in the Public Domain?
I’m pretty sure my university won’t accept it if it were, so in that case I can’t use it.