on 21 December 2011
It is easy to see that today's bird distributions have changed in the last 100 years. But what were they like 1000 years ago - or maybe 10,000 years ago? In fact what about 1 million years ago or indeed 10 million years ago? There are many questions that we should ask ourselves. For example, why are Tree Sparrows common in Asia and declining in much of Europe? Why are there more species of warblers than there are tits? How do Blackcaps and Garden Warblers manage to live side by side without one ousting the other? Why do Yellow Wagtails migrate long distances while Pied Wagtails hardly move from the territory in which they were born? Some questions can be answered by classifying birds according to their bioclimatic characteristics.
Early chapters in this book explain the major changes in the Palearctic landscape over the last 65 million years through many periods of glaciation and aridity with sea levels often vastly different from what we know today. Not surprisingly it is an area of research with differing opinions. Some believe that many lineages of present-day birds survived the catastrophic event 65 million years ago (known at the K/T Event) when the dinosaurs were driven to extinction. However some people still claim that avian radiation occurred after that. Finlayson discusses the theories and considers each view. He explains that species frequently respond to climate change by moving location to keep to their ideal ecological conditions. However when such changes happen over many thousands of years often the species adapt to their environment - while those that can't adapt become extinct.
Each group of birds is then assessed separately with evidence of their development over time. This part of the book contains a huge amount of information, but there are plenty of interesting facts if you delve deeply into the somewhat heavy text. For example there are two types of Azure-winged Magpie - one in Spain and Portugal, and the other in China, Japan and Korea. Everyone had assumed that those in Europe had been brought back from China by Portuguese sailors. However from fossil remains from Gibraltar have shown that they were there all the time - well at least for 40,000 years!
This is a serious book that will be welcomed by evolutionary ecologists for whom the level of analysis is fascinating, but for most bird enthusiasts it is an area of research that leaves them cold. There are 29 colour photographs, mostly by the author, and the book is packed with statistics. For those that persevere to read it fully there is plenty to learn.
on 28 December 2011
Despite having a small reservation about this book (of which more below), I have no hesitation in giving it five stars, as it is a mine of information for anyone with an interest in Palearctic birds.
Clive Finlayson presents the stimulating idea that the avifauna of the Palearctic became established in the `turbulent times' before the glaciations, and that those bird lineages that have persisted until the present day have done so by being able to survive `severe and rapid' periods of climate change. In support of his argument Finlayson presents a large amount of research and information that would otherwise remain obscure (at least to me), and in this respect Avian Survivors is worth owning for the Bibliography alone.
What, then, is my reservation? Well, in the book's introduction Finlayson mentions his admiration of R. E. Moreau's 1972 classic, The Palearctic-African Bird Migration Systems, justly noting that it is a model `of how to write science in a clear, concise and engaging way'. Unfortunately, this is a trick that to my mind Finlayson hasn't quite pulled off, for though the opening and closing chapters are fascinating, the middle section (chapters 4 to 18, which deal in turn with related groups of birds, beginning with shrikes, crows and orioles, and ending with wildfowl and gamebirds) are rather too heavy and repetitive to digest easily by reading in a systematic fashion. In fact, after a while I gave up and instead read the closing chapters before dipping back into the middle section to read about groups of birds that hold a particular interest for me.
But don't let the above caveat put you off. This book provides a fascinating insight into just how the avifauna of the Palearctic was shaped; it thoroughly deserves to be read and its content thought about.