快猫短视频

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IN 1729, French astronomer Jean-Jacques d鈥橭rtous de Mairan carried out a simple, but ingenious, experiment. De Mairan had noticed that the mimosa plant opened its leaves during the day and closed them at night. To find out whether it was responding to sunlight, he shut the plant in a cupboard for several days and sneakily observed its behaviour. To de Mairan鈥檚 amazement, the plant continued to open and close its leaves as normal. He concluded that it must contain some form of 鈥渋nternal clock鈥�.

快猫短视频s are now seeking the existence of similar mechanisms in humans. Their work has included observations of the sleep patterns of volunteers cut off from the outside world, global surveys of the time people wake up, and animal studies looking for mechanisms that keep our circadian clocks ticking.

In Internal Time, Till Roenneberg, a chronobiologist at the Ludwig-Maximilians University in Munich, Germany, takes readers on a journey through this mysterious area of science. He explores why some people are larks and others owls, why jet lag can be so debilitating to travellers, and why teenagers struggle to get out of bed in the morning. Roenneberg also examines how this work has important consequences for individuals and society: teenagers might be more productive if classes started later, for instance.

Most chapters follow the same format, with Roenneberg presenting a fictitious case-study as an introduction to the relevant research. One chapter, for example, takes readers on a visit to the year 2210 and the headquarters of the World Agency for Space Settlements, which has invited a chronobiologist to advise on how humans鈥� internal clocks might be affected by life on other planets. Roenneberg is a knowledgeable guide, with a talent for making difficult concepts clear and convincing. But these fictional parts often feel laboured and out of place.

Nonetheless, this is a fascinating introduction to an important topic, which will appeal to anyone who wishes to delve deep into the world of chronobiology, or simply wonders why they struggle to get a good night鈥檚 sleep.