Why go multicellular?
Bacteria are very successful. They’ve been around for billions of years, as compared to hundreds of millions for multicellular creatures. They have survived mass extinctions that wiped out things like the dinosaurs and others. Today, we look at salpingoeca rosetta, which can live as either a single celled creature, or in a multicellular colonial form. We compare that to the experimentally evolved multicellular colonies of yeast we introduced in the previous episode, episode 72; and examine how the multicellular creatures came about, and how and why they are no longer able to return to a single celled lifestyle.
Here’s an article about work by Nicole King, that introduced me to salpingoeca rosetta.
Here’s an article that examines genetic ratcheting, the tendency for evolution to take steps that it cannot take back.