There doesn't have to be deterministic screening for scientists to get the message. Events like the one described in the link below don't exactly impart confidence in an evolutionary biologist that they'll continue to get funded if they stay in America:
http://www.telegraph.co.uk/news/worldnews/northamerica/usa/6...
I guess if they are screening for the word evolution then that's pretty dumb though. I have a hard time believing that's still the case since Bush left office.