When we think of bird pollinators we – at least we in the Americas – think first of the hummingbirds: “They dominate the scientific literature, natural history documentaries, and our wider consciousness of what constitutes a ‘pollinating bird,’” as Jeff Ollerton rightly says.
But there are, Ollerton thinks, 1,380 bird species that may be pollinators (and some 20,000 bird-pollinated flowers), and part of the purpose of his new book, the impressive (and delightful!) Birds & Flowers: An Intimate 50 Million Year Relationship is to highlight other bird families that pollinate.
Ollerton is a renowned expert on biodiversity and pollination; this book is a supplement of sorts, a continuation, of his 2021 Pollinators and Pollination. Based in Denmark and the U.K, he’s peripatetic, and his book is full of bird examples from around the world, such as the gorgeous Scarlet Honeyeater, an Australian (photo by Geoff Park):
and the Blue-manteled Thornbill, shown below, right, feeding on the ground in the high Andes of Ecuador (photo by Jesper Sonne):
Given these many and varied bird species discussed in the book, Chapters 2 and 3, which set forth a good primer on bird taxonomy, are particularly welcome. This is not, it should be noted, the sort of book in which a journeyman nature writer distills the ins and outs of some discrete marvel of natural or physical science to a lay readership. Birds & Flowers includes a good deal of scientific detail and sophistication – but nothing you, as an intelligent layperson, interested in the subject and willing to take the time to read with a bit of care and patience, can’t handle.
Take, for one example, MEPP and LEPP. It was posited in 1970 that flowers would adapt to the pollinators that moved the most pollen and thus most effectively ensured the plant’s reproduction – the “Most Effective Pollinator Principle.” Later, though, and counterintuitively, it was shown that flowers could, and did, adapt to less-effective pollinators, as well. Which, of MEPP or LEPP, is more common in nature? (Or, as Ellerton puts it, which is the principal principle?) That’s still to be determined, though, Ollerton says, “there’s a growing body of evidence that points to the LEPP being more common than we realise.”
And why do many plants force their hummingbird pollinators (such as the Buff-tailed Coronet in Columbia, below, photo by Alexander Schlatmann) to hover to feed, instead of providing them a floral perch?
Hovering costs a lot in energy; the point, however, may be to force the birds to move between flowers more often, thus distributing the pollen more effectively.
A good deal of Birds & Flowers book involves aspects of the bird/plant pollination relationship that are yet unknown. After finishing the book the reader will need no convincing of Ollerton’s observation that “we have an iceberg understanding of biodiversity and ecology: the knowledge that’s on the surface is just a fraction of what’s hidden from us.”
Still, even all the stuff that’s on the surface of “the iceberg” is, in Ollerton’s telling, fascinating, and sometimes mystifying. In the latter category, for example, is his question “Why is Europe so weird?” For many years it was thought that bird pollination of flowers did not exist in Europe. “As is so often the case with common knowledge,” Ollerton writes, “it was wrong.”
There are, it is now known, a few specialized European plants that are pollinated by birds – but very few. In this regard Europe is a distinct and strange outlier in comparison to other continents, for some reason still to be discovered.
It’s a pleasure to spend time with Ollerton’s prose; as a writer, he’s sometimes quirky and rollicking (with analogies to Led Zeppelin and Monty Python) — but quirky and rollicking in a good way. Overall, he’s terrific, with suitable patience for his readers, and generous with his praise and citation to the work of fellow scientists.
Ollerton’s penultimate chapter includes some dismal statistics about recent extinctions, and endangered and vulnerable bird species. Quoting one of those fellow ecologists, he makes an often-overlooked point – an especially apt one in a book about a co-dependent relationship such as pollination: “What escapes the eye, however, is a much more insidious kind of extinction, the extinction of ecological interactions.”
In other words, when a bird goes extinct, so do specialized bacteria, fungi, and parasites that it houses, and so, maybe, do the plants it pollinates.
But in his last chapter, Ollerton disclaims pessimism about the environment and the natural world, and gives all the reasons there are to be hopeful about humans and other living things. He’s so good as a scientist and a writer that . . . you believe him.
_________________________________________________________________________________________________
Birds & Flowers: An Intimate 50 Million Year Relationship. By Jeff Ollerton. Pelagic Publishing, London. $26, February 13, 2024. ISBN 978-1-78427-451-1 (hardback); ISBN 978-1-78427-452-8 (ePub).
Source link