Taking Flight How Animals Learned to Fly and Transformed Life on Earth

Having just reviewed the 2015 book On the Wing, I continue my brief two-part foray into the evolution of flight with Taking Flight by writer and conductor Lev Parikian. In a book that is full of wonder and humour, he marvels at the many different strategies for flying that have evolved in primarily insects and birds. However, the somewhat muddled explanations of flight mechanics and limited attention for other groups make for a somewhat uneven book.

Parikian is the author of five previous books on music and the natural world. His 2018 Why Do Birds Suddenly Disappear? told how, as a self-proclaimed lapsed birdwatcher, he refound his passion for it in his fifties. He has also contributed to the BTO anthology Red Sixty Seven, The Guardian's Country Diary column, and Bird Watching magazine, so knows a thing or two about birds. Now, in his sixth book, he delves into the story of the evolution of animal flight.

Flying creatures are so ubiquitous in our lives that it is easy to take the whole phenomenon for granted. The strongest impression this book leaves is that of Parikian seeking to re-enchant his readership, grabbing you by the scruff of the neck from the opening encounter with a blue tit to remind you that: "It flies. It. Flies." (p. xiii). This sense of wonder infuses the book, whether it is flies capable of landing upside down on the ceiling—"we should, if we were properly curious and fascinated, be texting, 'I BEHELD A MIRACLE' to all our friends" (p. 59)—or awaiting the annual return of swifts to our skies—"as I roam the streets of south London, I'm a liability [...] head up, staggering shambolically into bollards and bus shelters, ready to harangue random passers-by with a hoarse, deranged bark of 'They're here!'" (p. 199).

I will not deny that his enthusiasm is infectious and is helped along by a healthy dollop of humour and jokes. There are colourful descriptions of male stag beetles with massive mandibles whose ungainly flight says "We're not really supposed to be doing this, but if you absolutely insist" (p. 50), or of pterosaurs whose fourth finger is "noticeably, weirdly, excessively long. A veritable überfinger. The kind of thing you'd use to get a ping-pong ball out from behind a radiator" (p. 111). There are pop-culture references, such as swifts whose "chief asset is speed. Speed and manoeuvrability. Speed, manoeuvrability and a fanatical devotion to the air" (p. 201). There is the occasional well-timed f-bomb, such as aforementioned flies landing upside down: "it seems weird and unnatural, a defiant 'fuck you' to everything we think we know about gravity" (p. 59). And I have yet to come across a more amusing explanation of the difference between taxonomical lumpers and splitters: "a 'lumper' would regard all Magnum ice-creams as the species 'Magnum', regardless of flavour; a splitter would deem the Double Raspberry Magnum and the Salted Caramel & Glazed Almond Magnum two separate species. Glad to have cleared that up for you" (p. 153). Admittedly, some of the jokes are a bit of a stretch. How did pterosaurs get airborne? "Perhaps they flung each other into the air with a primitive trebuchet" (p. 113). I guffawed my way through this book, but your mileage might vary, depending on how you like your popular science.

Entertaining as Taking Flight is, I do have some criticism. First, the book feels somewhat uneven due to his choice to spend six chapters each on insects and birds (because they have the greatest diversity in morphology and flight styles), but only one each on pterosaurs and bats. As a consequence, many chapters are not strictly about the evolution of flight, but more about the diversity of flyers that evolution has given rise to. Chapters feature, for example, bee swarming and butterfly migration, or the adaptations that allow hummingbirds to hover and albatrosses to soar. He includes most of the theories on the evolution of flight covered in On the Wing and has read up on the literature, mentioning, for instance, the quadrupedal launching model for pterosaurs that Alexander left out. However, he omits other ideas, for instance, how flight in insects might have started simply by steering one's fall (so-called directed aerial descent), as was reported in 2005 for ants by Steven Yanoviak and colleagues.

Second are Parikian's explanations of the biomechanics of flight. Rather than dedicating a chapter to the basics, he delves straight into the story of evolution, starting with the earliest insects, and drip-feeds you bits of information throughout the book. The opening Author's Note admits he has come to this topic as an eager layman, but despite having consulted relevant literature, his explanations leave something to be desired. For example, he writes that lift is generated by leading-edge vortices increasing the speed of air flowing over the wing, which lowers air pressure, which increases lift. However, both Alexander and Gregory Paul's book on pterosaurs point out that this is an incomplete and even misleading explanation. If I have understood these authors correctly, most, if not all, lift is generated by the downward orientation of the trailing edge (the back of the wing), which sends the airflow down and back. It is the downward component of this, and the vortices formed behind the trailing edge, that generate lift. Furthermore, even as Parikian defines certain terms, he uses others without explaining what they are, such as angle of attack and camber. Plus, he makes it sound as if camber is the same as a wing's surface area, which it is not; it refers to the curvature of the wing, more specifically, the difference in curvature between the upper and undersides. Thus, when he explains that bees deal with the additional load of pollen by making their wing strokes deeper, I am not actually sure what that looks like. There are no diagrams included, which would have been helpful given the level at which this book is pitched. Unfortunately, I am left with the impression that, unless you are already familiar with the basics of animal flight, you might come away with a muddled understanding of it.

Overall, Taking Flight is a humorous look at the many different flyers and ways of flying that have evolved. Look out, for example, for the insane way in which dragonflies reverse. Parikian is unapologetically enthusiastic, and the book is all the more enjoyable for it. However, for a clearer and more factual explanation of how flight works, supplementary reading will be required, and On the Wing remains relevant.