The modern world

Our biological clocks are the result of three billion years of evolution.

They help us anticipate and respond to nature's rhythms. But in the modern world these natural rhythms are disrupted by electric lights, alarm clocks and the demands of a 24-hour society.

Next week's article will look at how our circadian clocks cope - and sometimes fail to cope - with these new demands.

This is the first instalment of a three-part series about the circadian clock that controls your sleep cycle, hormone levels and body temperature.

Related links:

» Keeping in sync with nature's rhythms

» Pop your pills, but at the right time

Gary Hayden is a freelance writer whose specialisations are: education, science & philosphy, health & wellbeing, travel and short fiction. E-mail: gary@garyhayden.co.uk

This article was first published in Mind Your Body, The Straits Times.