July 9. Clears up at noon. [...] There is a smart shower at 5 P. M., and in the midst of it a hummingbird is busy about the flowers in the garden, unmindful of it, though you would think that each big drop that struck him would be a serious accident.
Sept. 1. P. M.—To Walden. [...] See how artfully the seed of a cherry is placed in order that a bird may be compelled to transport it. It is placed in the very midst of a tempting pericarp, so that the creature that would devour a cherry must take a stone into its mouth. The bird is bribed with the pericarp to take the stone with it and do this little service for Nature. Cherries are especially birds' food, and many kinds are called birds' cherry, and unless we plant the seeds occasionally, I shall think the birds have the best right to them. Thus a bird's wing is added to the cherry-stone which was wingless, and it does not wait for winds to transport it.
H. D. Thoreau