The Inner Clock review: How bad is modern life for our body clocks – and what can we do?

Humans defy internal clocks; the little penguin (pictured below) lives by them

Alex Ramsay/Alamy

The Inner Clock
Lynne Peeples (Out 24 September: Bloomsbury Tonic (UK); Riverhead Books (US))

The little penguin (Eudyptula minor), a tiny, blue bird living off the coast of southern Australia, speed-wobbles from the ocean to its burrow home at the same time every day – just after sunset. Timing is crucial: too early and they miss the day’s final catch; too late and encroaching darkness makes them prey for orcas and feral cats.

Fortunately for those who come to watch, environmental cues like sunlight and phases of…