Like most animals, plants also sleep at night. At least, many do, but not, unfortunately, Arabidopsis, and our scientific over-reliance on this one species has hampered understanding of nyctinasty, sleeping movements of leaves. A new commentrary in PNAS discusses the genetic basis for sleepy plants, and is well worth a read:
Genetic basis of the “sleeping leaves” revealed. PNAS USA 6 July 2012, doi: 10.1073/pnas.1209532109
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