A question that often arises when I encounter YEC's is some variation of the following:

How can species X possibly evolve from species Y (without direct intervention from some ficticious sky tyrant) ? 

Any attempt to explain common examples (such as Goulds thoughts on the evolution of the eye) tend to be accompanied by chants of 'na-na-na...da bible says..na-na-na' and the smell of smoking neurons. How in the name of the FSM are you supposed to conduct a rational discussion with someone who keeps pointing to their little black book of fairy tales whenever said discussion becomes more technical than ' would you like cream or sugar ' ?  So, to avoid wasting time, I generally try to end the debate with something along the lines of:

 'The short answer is: unlike the deluded masses of True Believers, we don't yet have all of the answers.'

But, as the following article demonstrates, we are getting closer with each passing day.

Scientists find missing evolutionary link using tiny fungus crystal

WEST LAFAYETTE, Ind. - The crystal structure of a molecule from a primitive fungus has served as a time machine to show researchers more about the evolution of life from the simple to the complex.