Faced with a sharp temperature change, many animals make an immediate behavioural response (seeking a more equitable environment). Placed in a temperature gradient, most cold-blooded animals will move about and gradually spend more time around a preferred temperature, which is a function both of the animal's species and of its thermal history. As temperature varies over the course of the day, behaviours include selecting suitable micro-habitats, basking, seeking shade, burrowing (which protects from both extremes of outside temperature), aggregation with conspecifics [15]; appropriate alternation between these can achieve a remarkably constant body temperature. On a longer timescale, temperature may alter the activity of endocrine organs and become a part of the complex stimulus of migration. Silicon systems controlling an autonomous mobile robot [16] might be at liberty to use such behaviours, but in general there is no escape for electronics from its given environment. There also seems to be no electronic counterpart for temperature-related activities such as nest-building, or the rather unique strategies of Homo sapiens...such as inventing air-conditioners [17].