Do you like butter

When I was a boy, we used to ask this ritual question whenever we found buttercups. We would hold a flower under the chin and if the yellow reflected, it meant that you liked butter. I had no idea, but it was only very recently that science was able to explain this phenomenon. To quote Wikipedia: the directional reflection of the light beam comes from the transparent epidermal surface layer composed of very flat cells loaded with carotenoid pigments, whilst a diffuse yellowish colouring comes from the scattering of light by an underlying layer loaded with starch granules. Together, this produces that intense, glossy yellow which probably plays a role in attracting insects. So, did you like butter too?