Yes, there is evidence, but you don't need AI, per se. Just automation in its various forms (robots, software, etc.):
http://www.economist.com/news/briefing/21594264-previous-tec...
http://www.npr.org/2011/11/03/141949820/how-technology-is-el...
http://www.nytimes.com/2011/03/05/science/05legal.html?_r=0
Automation is moving up the skill / knowledge chain.