He's saying that the creation story is an allegory. Just as Christ spoke in parables to illustrate a point, it's my opinion that some parts of the Bible are allegory.
I believe the take home point of Genesis is that with the additional evolved prefrontal cortex comes self-realization and the knowledge that we will someday die. A lower animal has no such realization, so they live still in the Garden of Eden. We have been "cast out" because we have the ability to interpret our own mortality. This makes every pain worse, every sickness scarier, and the idea of life itself more frightening, because we know it will someday end. In other words, ignorance is bliss.
That's just my two cents.
I believe the take home point of Genesis is that with the additional evolved prefrontal cortex comes self-realization and the knowledge that we will someday die. Let's say you're trying to explain that concept to someone who has no idea what a prefrontal cortex is and no way to figure it out, such as someone living 5,000 years ago.
Would you...
A. Come up with a version of what you've said here that requires no knowledge of the prefrontal cortex (such as "When God made man's mind much greater than the inds of animals, etc., etc.")
B. Spend 1,400 words telling the person about a universe being created in a week, followed by a woman being created with rib surgery and deceived by a talking snake? Don't forget this version has to include the idea that plants existed on Earth before there was a sun.
It's very likely you'd choose option A. So why would the infinitely wise Almighty choose the ham-handed option B?
Possible answer? Because option B is the truth.