What Good Are Bugs? by Gilbert Waldbauer, Harvard University Press, £19.95/$29.95, ISBN 0674010272 Reviewed by Jonathan Beard
A BUG in your software? Complain. A bug on your arm? Swat it. Entomologist Gilbert Waldbauer from the University of Illinois plans to stop that second reaction: he wants to change readers’ attitudes toward insects. He explains, with hundreds of examples taken from research old and new, the myriad ways in which insects help plants and animals – and that does include people. And, in What Good Are Bugs? Waldbauer’s view of the web of life is usually from the insect level horizontally, or upwards, toward vertebrates. As numerous as bugs are, microbes outnumber them as ants do humans.
Many plants depend on bugs to disperse their seeds, not just for pollinating their flowers. Carnivorous plants such as the honeydew prey on them. This may be familiar stuff but Waldbauer has surprises for us: he credits insects with the control of plant and animal populations. Most little acorns do not grow into mighty oaks, because so many are eaten by acorn weevils, among other insects. In many environments insects, especially ants, are the dominant herbivores. Their biomass, Waldbauer points out, is often greater than that of all the vertebrates in the same ecosystem.
Advertisement
Of course, among the animals kept in check is Homo sapiens. Insects spread parasitic diseases such as malaria and viral diseases like West Nile encephalitis, killing millions of people a year. But the passages devoted to insect attacks on people, their animals, and crops sometimes go against Waldbauer’s stated purpose. He wants to demonstrate the interdependency of life: before appropriate dung beetles were introduced to Australia, grass could not grow in pastures covered with cattle excrement, and the herds were starving. The beetles enabled both plants and animals to thrive. But the plasmodia of avian malaria – spread by introduced mosquitoes – that are killing off Hawaii’s native birds are simply part of the same web. They need hosts in which to be fruitful and multiply, and honeycreepers are available.
What Good are Bugs? is well written, and provides a good summary of the research on important areas of insect ecology, with references to the original sources. It could have been shorter, and better organised – many sections merely group examples – but each one is fascinating.
Waldbauer just could not skip the tsetse fly’s mammary glands, or his clever explanation of why so many insects feed on just one plant species. Clearly he is a scientist in love with his research.