By Helen Briggs
Plants have a built-in capacity to do maths, which helps them regulate food reserves at night, research suggests.
UK scientists say they were "amazed" to find an example of such a sophisticated arithmetic calculation in biology.
Mathematical models show that the amount of starch consumed overnight is calculated by division in a process involving leaf chemicals, a John Innes Centre team reports in e-Life journal.
Birds may use similar methods to preserve fat levels during migration.
The scientists studied the plantArabidopsis, which is regarded as a model plant for experiments.