At 7.15 a.m. today the fire alarm went off in my hall. In the bleariness that generally defines me at any time before, say, 3 p.m., I floundered around in absolute confusion for a while before I realized that it wasn’t my alarm clock having delusions of grandeur, and stumbled downstairs. Trying to find something to do other than shiver while waiting for the fire alarm drill to end, I squinted at a plaque on the Anatomy Building saying something about Charles Darwin having lived there. And I thought about London in 1666, a city built of timber and pitch, ignited by a spark and then burning for four days, and I thought about fire alarms, and fire drills to make sure the fire alarms work and people react the way they’re supposed to. And I somehow drew parallels between this and Darwinian evolutionary theory. And then the fire drill was done, and we could all go back in, and I went upstairs and got back into bed and fell asleep.