Today on the Endless Swarm, one of my favorite Krulwich videos about insects, from the Morning Edition entitled "Look Up! The Billion-Bug Highway You Can't See." I was reminded of this amazing fact when hiking in Napa yesterday. In the early spring cold, there wasn't much in the way of insects in the forested understory of Bale Grist Mill State Park, save for a few flies warming themselves on the rare patch of dappled sunlight, and a few newly-moulted mayflies on streamside rocks, awaiting the sclerotization of their soft exoskeletons. But if I allowed myself to look up, I could see huge swarms of insects, flies and midges and moths and more, spiraling up the column of air high in the canopy, far from any easy observation. It's times like this I regret my lot as a terrestrial flat-footed ape!