of the engine and the road feeling a lot like being in an airplane. I could feel the first soft breezes of jet lag wafting through my mind. My body felt heavy and slightly ill. Outside, a real wind was kicking up tiny whitecap waves.
This was the same water that had swamped the Lakeview house. It looked calm now, silty and greenish in the cool of the coming evening. Hundreds of pilings and wide sections of concrete showed where the damaged southbound bridge was being rebuilt. I wondered if this might be part of the mystery of violence; the way something could look so calm and peaceful, right up until it didn't.
In my hazy state of mind, the thought seemed bigger than this particular water, this particular bridge. I felt like it applied everywhere. A little old lady with a tripod cane who puked out a needle-toothed demon. A favorite uncle who, on his death, turned out to be more than I'd ever known. A simple, physical attraction to a good-looking man with what my mother would have called a kind mouth that turned into a night of sex, a mass of guilt, and a set of divorce papers that I still hadn't told Aubrey about.
I must have sighed, because Aubrey looked over at me, concerned.
"Hey," he said. "You doing all right over there?"
"I was just thinking about what Karen said," I lied. "The whole thing with the rider taking over people's minds. About how Mfume loved it by the end. I just don't get that."
"There's a fair amount of precedent," Aubrey said. "Not in vertebrates, particularly. But wasps, caterpillars..."
"Ooh," I said, curling up in the seat. "I love it when you talk geeky."
I didn't usually flirt with Aubrey. I didn't usually flirt with anyone. It was the exhaustion, I told myself. And the adrenaline crash from the rider's ambush. It wasn't because I thought Karen Black was smarter and sexier and more competent than I was. Flirting with Aubrey because I didn't measure up to her would have been juvenile and stupid, and I would never do anything like that.
Yeah, whatever.
Still, Aubrey laughed a little, smiled a little, ran his hand through his hair like he was suddenly self-conscious about how he looked.
"There was an example they talked about a lot when I was in grad school," he said. "Glyptapanteles. It's a family of wasps that parasitize moths. Well, caterpillars."
"A wasp as a parasite for a caterpillar?" I said. "How do you fit a wasp inside a caterpillar?"
The far shore of the lake was just coming into view. We had almost passed over the water.
"You don't," he said. "The wasps lay eggs in the caterpillar. When the eggs hatch, the larvae live off the host's body. They eat it, but they don't kill it. Eventually, they pop out and pupate."
"Pupate," I said. "Meaning turn into grown-up wasps, right?"
"Yeah," he said. "While they're doing that, they're vulnerable. There are a lot of predators who could just come along and eat them, so there's a lot of evolutionary pressure to keep that from happening. Some wasps, the pupae are cryptic and well hidden. Some of them the larvae get in a really hard-to-reach place before they pupate. Glyptapanteles stay right by the caterpillar they came out of. And the whole time that they're turning into wasps, the caterpillar guards them. Anything comes along and tries to eat the pupae, it knocks them away."
"So do they leave a larva behind or something?"
"No," he said. "They all leave. It's not like they're still in there driving the caterpillar's body."
"Then why does it do that?" I asked.
"It's been changed," Aubrey said with a shrug. "We don't know how yet. When you get down to that level of behavior modification, you might just as well say that the caterpillar loves the wasps. It's not like there's a better way to put it."
We passed back onto dry land. The lake faded away behind us in the trees. The sun was off to our left, growing red and heavy in the last few degrees until sunset. Aubrey was a silhouette, the shadows of the roadside trees stuttering like an old movie with its sprockets slipping. I had the uncomfortable sense that I'd done something wrong. I'd sort of been coming on to Aubrey-something I'd tried not to do in these last few months-and the end result was a view of love and parasites that actually left me feeling a little queasy. Normally, Aubrey's biology talks were pretty