Monday, 25 January 2010

Dazzled and Deceived – Peter Forbes *****

Subtitled ‘Mimicry and camouflage’, this is a fascinating exploration of the use of visual trickery to disguise the nature of objects both in the living world and in the military. Along the way we trace the gradual growth of understanding of how creatures in the wild use mimicry to pretend to be what they aren’t (for example, imitating a poisonous creature, or an insect pretending to be a plant), or camouflage to become less visible against a particular background.
The two aspects of natural visual deceit that really struck me in reading it were the situations where something we all ‘know’ to be true isn’t – for instance, the chameleon uses its colour changing for display, not for camouflage – and in the incredible complexity of some butterfly mimicry where, for instance, the female of one species might look like any one of four very different nasty tasting butterflies.
What is also very engaging is the way that Peter Forbes carefully dissects the over-simple evolutionary idea of ‘the ones that looked more like the thing they were mimicking survived better’ to transform it into a modern understanding of the complex mechanisms behind such mimicry. All too often, the simplistic approach seems to apply too much choice to the concealed creature, as if it could decide to look like something else, where actually its ability to mimic depends on having certain characteristics (even if they weren’t previously used) already.
In the interlaced chapters on wartime camouflage, it is amazing just how amateurish early attempts at camouflage were – and how ‘facts’ about camouflage were derived with very little real experimental evidence. In the early days there were two opposing camps – the artists and the naturalists. Perhaps surprisingly given his background, Forbes doesn’t inherently side with the naturalists, but rather gives both sides credit for their contributions. Having said that, I’m surprised there isn’t more about the physics, as in the end camouflage is an attempt to manipulate photons – really neither artists nor naturalists were arguably the right people to sort it out.
There were one or two minor weaknesses. Because of this concentration on artists and naturalists, there was nothing about modern technology for hiding things, whether it’s stealth technology or invisibility cloaking. More significantly, although Forbes’s style is always approachable, I found a few of the biology sections a little heavy going. It wasn’t always easy to work out just what was supposed to be causing an effect. It’s not that Forbes doesn’t know his stuff, but rather than he knows it too well and doesn’t explain in quite enough detail to get the message across to the non-biologist. By comparison, the military sections were all very readable without that slight problem.
Overall a wonderful topic that really hasn’t been given enough coverage, especially given its importance in understanding the mechanisms of evolution better, and an excellent book. Highly recommended.
Paperback:  
Review by Brian Clegg

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