They really
are getting dumber:
In 2009, 54% of Republicans and 64% of Democrats said humans have evolved over time, a difference of 10 percentage points. Today, 43% of Republicans and 67% of Democrats say humans have evolved, a 24-point gap.
Looking at the results another way, in 2009, 39 percent of Republicans thought humans existed in their present form in the past (i.e. "Garden of Eden"). In 2013, that number is 48 percent.
So three years ago, conservatives looked around at each other and said, "we're kinda stupid, but not stupid enough. Let's work on that!" Mission accomplished.