Bird Migration ¦ Insect Migration ¦ Mammal Migration ¦ Migration in the Sea

It's been some time since I read an information book where the end of the right-hand page didn't also mean the end of a sentence and usually the end of a concept. The tyranny of the two-page spread is so nearly absolute that one wonders how much useful material gets left out in one place and how much padding gets put into another so that all the frames shall be equally filled. In presenting this migration quartet, the publishers have wisely decided to buck the trend (rubbing it in by spelling 'Usborne' wrong in their bibliographies) and let the full stops fall where the authors meant them to (even when it's after a preposition).

The authors have a fascinating brief and real subject knowledge backed up by good pictures and maps, so the result is four riveting end-to-end reads unfettered by gimmicks. They define migration as 'any planned journey from one place to another' which allows them to tell us not only about the spectacular artic tern and monarch butterfly but about the lowly ambitions of the limpet. We end up understanding a lot about why animals move from place to place (just like ourselves, it's mainly sex, food and comfort) and how they do it.

The examples chosen are wonderful in their variety. We learn that American leafhoppers, after wintering in Texas, hitch a thousand kilometre ride on a southerly wind in time to crunch the springtime beet crop in South Dakota, and we share the slow, single-file trudge of the spiny lobster along sixty miles of Atlantic seabed.

But as well as reasons and achievements the authors remember the question 'how do they find the way?' and offer good explanations - moths navigate by the moon, salmon by sense of smell and lemmings by continuous reconnaissance. And when they don't know they own up, so we don't find out about where mature eels disappear to, or how baby turtles spend the first eighteen months of their oceanic life.

This quartet is a splendid addition to any collection of information books in a primary or secondary school that seeks to promote what books do best - enable a meeting of minds between reader and author.