ABSTRACT
Micro-organisms are ubiquitous. They are present in the soil of our gardens, in the air that we breathe and in the sea around us. They invade and colonize our bodies, both causing illness and being protective of health. They spoil our foods and yet are involved in the manufacture of some. Micro-organisms are able to grow in a remarkable range of habitats, which range from the relatively hospitable, often supporting a wide diversity of microbial life, to the extremely hostile, where only a single type may proliferate. An example of an extremely hostile environment, which has attracted much recent interest, is the vent of undersea volcanoes – the realm of the hyperthermophile. Despite enormous differences in the nature and geobiology of the various environments, it should be appreciated that the same underlying factors govern the life and death of micro-organisms irrespective of the nature of the environment. Equally, their behaviour is governed by fundamental rules.
