On an Earth plummeting toward mass extinctions of many animal, plant, and bird species, passionate scientists and naturalists are striving to accomplish the impossible, to save the species closest to the cliff’s edge. To do that, dramatic and imaginative solutions are employed, and to do that, knowledge is key. In the case of our 10,000-plus bird species, where, when, and how they fly is a crucial knowledge piece, and until the past few decades, was a scientific gap. “Flight Paths,” written stylishly and cogently by America science writer and naturalist Rebecca Heisman, plugs the gap with a wonderfully informative recent history of the often-unknown heroes who have revolutionized ornithological understanding of avian flight. Progressively covering better and more authoritative surveying across the immense distances over which birds, incredibly, migrate from the birder with her binoculars; to scanning moonlit skies in peak migration season; to clumsy early leg bands; to lighter and lighter on-bird trackers; to the stunning use of radar; to mass community science efforts; to satellite tracking; and (the most amazing feat of all, to my mind) analysis of radioactive isotopes in feathers … all this is explicated. Talking to and visiting a band of modest and sometimes eccentric ornithologists, engineers, and birders, the author brings to life the excitement of rapidly escalating understanding of the creatures that have been in our planet’s skies long before we walked its lands. Highly recommended, Flight Paths is.