We’ve known for about twenty years that maternal substances in the egg can influence how chicks develop, but the common assumption is that they are a means by which mothers manipulate their offspring in a way that suits the mother more than the chick.
What we’ve shown is the reverse: these substances are actually there to suit the chick. If we muck up the message in the egg experimentally, it is the chick that is penalized directly rather than the mother.
So let’s see, a whole bunch of mutations created birds and a whole bunch of mutations created eggs (not sure which came first, but evolutionists have that all figured out), and then a bunch of mutations created the capability to insert messages into eggs. That didn’t help, but a another bunch of mutations created the capability to interpret those messages and, Eureka!, evolution did it again. That’s just good solid scientific research.