If this is TRULY what current ET believes, then we should find, in all living things, partial structures that fail to have ANY function at this point in time, but are merely waiting for the last brick to be placed in the wall.
After all, the EYE is one of the many stumbling blocks:
1. It is so complex that the odds of random mutations occuring at the same time to form it are so great the Universe hasn't been around long enough.
2. Accumulating small mutations over time to form a functioning eye hits the same problem.
The eye. Did you miss that report this week where they found the link between the eye and the brain cells supporting the evolution?