Pardon me but I have to ask, as someone here might know...

Over this past weekend on Saturday afternoon (ET, NYC + PHL markets)[1] on an NPR station (in the car) I heard what I presume was a rebroadcast of a show on a theory about the creation of the first multi-cell organism. Typically, I pick up the name of the show and who the featured guest was, but this time I missed both. It was fascinating stuff and would like to listen to it in full.

Does this ring a bell with anyone?

[1] I realize each NPR station has its own schedule so this clue might not be helpful.