I don't think this is as surprising as the article makes it seem. Gene expression regulatory networks are often several layers deep. It's like if foo:

I don't think this is as surprising as the article makes it seem. Gene expression regulatory networks are often several layers deep. It's like if foo: if bar: if baz: thing 1 else: thing 2 modification 1 else: thing 3 if foo has been off for millions of years, and bar and baz have not broken since then, then enabling foo brings back the whole ancient show. Plants have notoriously large genomes because they can't move around, so whenever they grow they have to adapt to the conditions in that place. It makes sense to keep a lot of old code around just in case.