ADAPTATION AND CHANGE

Adaptation to variable and harsh environments is a central theme of evolution. From the North and South poles through the temperate regions to the equator, there is variability to learn to live with. Much of that variability follows a pattern and, in a sense, it is predictable. Daily, lunar and annual seasonal patterns of variability dictate the behaviour of nearly all forms of life. What is important here is that those events on Earth that relate to the cycling of the sun and the moon have remained unchanged for so long that animals have evolved adaptive rhythmical patterns of behaviour that are encoded in their genomes. The behaviour is instinctive and simply part of what they do with regularity.

But what about adaptation to erratic events that follow no pattern, fluctuating from minute to minute, and from hour to hour? In a single place, one may expect continuous variation of temperature and humidity, but if one were moving around continually in flight like a bumble bee, or running around on the ground like a mouse, the changes sensed would be quite different from those at a single location. So variation experienced by the organism is not simply about change with time, but also change from place to place.