Sunflower inflorescences absorb maximum light energy if they face east and afternoons are cloudier than mornings

  title={Sunflower inflorescences absorb maximum light energy if they face east and afternoons are cloudier than mornings},
  author={G{\'a}bor Horv{\'a}th and Judit Sl{\'i}z-Balogh and {\'A}kos Horv{\'a}th and {\'A}d{\'a}m Egri and Bal{\'a}zs Vir{\'a}gh and D{\'a}niel Horv{\'a}th and Imre M. J{\'a}nosi},
  journal={Scientific Reports},
The mature inflorescence of sunflowers (Helianthus annuus) orients eastward after its anthesis (the flowering period, especially the maturing of the stamens), from which point it no longer tracks the Sun. Although several hypothetical explanations have been proposed for the ecological functions of this east facing, none have been tested. Here we propose an atmospheric-optical explanation. Using (i) astronomical data of the celestial motion of the Sun, (ii) meteorological data of diurnal… 
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