Books I'm Reading: The Bird (November 7, 2011)

I've just finished Colin Tudge's  The Bird (Crown, 2008). The full title gives a little of the book's flavor--The Bird: A Natural History of Who Birds Are, Where They Came from, and How They Live. I imagine Mr. Tudge is an interesting man to talk with--about virtually any subject. Evidence of deep curiosity and subtle thinking is on every page of the book. I have no doubt that millions of people ask themselves from time to time things like "How do birds fly?" or "Are birds really dinosaurs?" or "Why don't woodpeckers get headaches?" Mr. Tudge has considered questions such as these, and many, many more, and he offers answers.

Having not long ago read this author's book The Tree (Crown, 2006), I had an idea of what to expect. The books are organized in the same way. Following a discussion of how birds are believed to have evolved (and, yes, birds do appear to be the descendants of a particular group of dinosaurs), Tudge lays out the entire world of birds as they survive today. Much of the book is a catalog of all the birds in the world, family by family, with discussions of where the birds in each family live, how they relate to each other within groups, and how the various families interrelate. While some families are very small--the peculiar remnants of once much larger groups, many are very broad and astonishingly diverse, with members finding their way into nearly all ecological niches available. It's impressive to see how frequently animals (in this case birds) have evolved independently along similar lines.

Tudge points out many examples of convergent evolution--for example, the case of swifts and swallows, which are not at all closely related. Swallows are passerines, or perching birds, with feet adapted to automatically cling to what they alight on--a twig or a wire fence--with a long back toe and a locking mechanism that allows them to hold on without using their muscles (one reason passerines don't fall out of trees at night when they roost). The swifts (family Apodidae) can barely perch at all (the root of the family name means "footless"). They roost by clinging to rocks, trees or buildings, and one or two species of swift spend almost their entire lives in the air. Yet, swifts and swallows have the same sickle-shaped wings, similar forked tails for maneuverability, and their feeding strategies are virtually identical--they hunt for insects at high speed on the wing.

The latter part of the book is more expansive, covering topics such as: how birds eat (and there are many strategies and adaptations for each strategy); the endlessly fascinating phenomenon of migration, with much attention to what makes arduous and dangerous journeys worth the effort; the sex lives of birds; the social relationships of birds; and the intelligence and modes of thinking of birds. On this last subject, the feats of memory of the Clark's Nutcracker and the Western Scrub-jay (both birds that cache food in the autumn for winter use) are particularly impressive--Clark's Nutcracker can hide and remember the hiding places of thousands of seeds each season. The final, somewhat melancholy chapter touches on the relationship between birds and humans and what the future is likely to hold for the birds of the world. There is much to lament. Many species are in rapid decline. He emphasizes that much more and better science is needed and that awareness built on good science will be essential to helping birds survive. Tudge ends on an only slightly hopeful note in an epilogue called "A Matter of Attitude," pointing out that attitudes about birds (and about animals and conservation in general), have long been dismally unappreciative. However, he believes that approaches are beginning to change, at least in some quarters, with scientists and others seeing birds as more intelligent, more socially complex, more thoughtful creatures than in the past. Let us hope Mr. Tudge is right, for birds are fabulously diverse and beautiful. We have lost too many already.