15 Questions for Evolutionists -- #6 How do evolutionists know that living things were not designed?

Question 6 in CMI's '15 Questions for Evolutionists' flyer focuses on the fact that one of the greatest challenges for evolutionists is that living things show too much design! If (as Francis Crick, the co-discoverer of the double helix structure of DNA, wrote) "Biologists must constantly keep in mind that what they see was not designed, but rather evolved" how do evolutionists know living things weren't designed?