Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.


Ancient roots of daily rhythm

The hormone that regulates sleep and other circadian processes in vertebrates also controls night-time behaviour in zooplankton, suggesting early evolutionary origins for the hormone.

Melatonin is produced by many organisms, but its function in invertebrates has not been clear. Maria Antonietta Tosches, Detlev Arendt and their colleagues at the European Molecular Biology Laboratory in Heidelberg, Germany, studied larvae of the marine worm Platynereis dumerilii, which move up and down in the water at certain times of the day. The authors found that the larvae make melatonin in the brain and that production ramps up at night. This boosted neuronal activity, which resulted in less swimming, allowing the larvae to drift downward.

Melatonin evolved in early animals to coordinate their behaviour with the time of day, the authors propose.

Cell 159, 46–57 (2014)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ancient roots of daily rhythm. Nature 514, 9 (2014).

Download citation


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing