Skulls in the Stars: Lord Rayleigh on Darwin

Darwin set out to show that insects play a crucial role in cross-pollinating plants, carrying pollen from one flower to another, and he published his results on orchids in a book in 1862, Fertilisation of Orchids. Among those results is the insightful observation that the colors and scents of flowers had evolved to attract insects and optimize the cross-pollination process.

This observation is what Rayleigh seems to be commenting on, and mildly criticizing. Rayleigh suggests that Darwin’s argument leads to the conclusion that insects must have vision similar to human vision — otherwise, why would a flower which is pretty to us be pretty to an insect? Rayleigh argues that this is a rather large assumption to make based on the limited evidence available in that era.

It’s well-known now that many insects are sensitive to UV, and plants look quite different to us in that spectrum. I have no idea what they look like to the bugs.