Not this week but A week

In the past year, This Week in Virology has rapidly become one of my favourite podcasts. Although, because of the way I do my podcast listening I've only heard the first few episodes from way back in 2008. After a while of not hearing one I was getting a bit worried I'd messed something up in compiling the playlist, but it turns out they'd missed a week.

The hosts are Vincent Racaniello, a virologist, and Dickson Despommier, who studies parasites. In this 2008-10-18 episode they had these adorable exchanges while working their way round from cichlid fish to talking about rabies.

Despommier: So you start mutating this gene and you get all these mouthparts. What does that sound like to you, Vince?
Racaniello, clearly unsure where Despommier is going with this: Viruses?
Despommier: Uh, that was a question. No, no, it was a broader question. It actually mimics the same situation of Darwin's finches. Darwin's finches can be controlled in terms of beak size and strength by a single gene. And if you mutate that gene in chickens you can get all of Darwin's finches represented in domestic chickens.
[...]
Racaniello: Is evolution a theory or a fact?
Despommier: Well you know, you teach this stuff enough and you start to consider it as a fact.
Racaniello: It is a fact, it's a law, Dick. Repeat after me: Evolution is a law.
Despommier: It's a rigidly controlled-
Both: *laughing*