Plus ça change... I was working with a professor running similar co-evolution experiments on the Java program ALife back in around '98. We had a great simulation of lions and cows, where the cows evolved to take spiral paths to munch the grass efficiently, while the lions evolved to rest while their blood sugar was high, and then run around looking for cows to eat when it dipped too low.

I'm glad the old evolutionary AI methods are still occasionally in use. I left AI about 15 years ago, and the whole field now seems to me to be machine learning whenever I see some new tool bring developed.