“Sleep served an important evolutionary function. Once Clem Pre-Mammal was done filling his stomach and squirting his sperm around, sleep kept him immobile and away from predators. Sleep was an aid to survival. But now it’s a leftover mechanism, a vestige like the appendix. It switches on every night, but the need is gone. So we turn off the switch at its source, in the genes.”

Ong winced. He hated it when she oversimplified like that. Or maybe it was the lightheartedness he hated. If Marsteiner were making this presentation, there’d be no Clem Pre-Mammal.

Camden said, “What about the need to dream?”

“Not necessary. A leftover bombardment of the cortex to keep it on semi-alert in case a predator attacked during sleep. Wakefulness does that better.”

“Why not have wakefulness instead then? From the start of the evolution?”

He was testing her. Susan gave him a full, lavish smile, enjoying his brass. “I told you. Safety from predators. But when a modern predator attacks — say, a cross-border data-atoll investor — it’s safer to be awake.”

Camden shot at her, “What about the high percentage of REM sleep in fetuses and babies?”

“Still an evolutionary hangover. Cerebrum develops perfectly well without it.”

“What about neural repair during slow-wave sleep?”

“That does go on. But it can go on during wakefulness, if the DNA is programmed to do so. No loss of neural efficiency, as far as we know.”

“What about the release of human growth enzyme in such large concentrations during slow-wave sleep?”