Fish eggs and Richard Jefferies.

I just heard on the radio the scientific explanation of how fish appear in a landlocked pond. The usual explanation was that birds transported fish eggs on their feet from other water sources. Now we know that fish eggs when swallowed can pass through a birds' gut alive and emerge in their faeces. Birds that have adapted to eat pondweed and such appear to reject fish eggs that are adhering to the plants, and during digestion they remain living to be excreted later. Remarkable.

If you wish to learn more about natural history, I would recommend Gilbert White's diaries as a good starting place. Very interesting early observations on flora and fauna. Then the essays and books of Richard Jefferies, beautifully written and closely observed studies made during his many perambulations in Wiltshire and elsewhere. W.H. Hudson and H.E. Bates are both excellent natural historians to consider, and Ian Niall ranks highly in my view as an engaging and accurate observer of countryside and wildlife. I have collected many first editions of Jefferies' work over the years and I read and re-read them with admiration. They scintillate with almost poetic brilliance.