Evolution is far more than black and white

The grey chi moth
The grey chi moth

When choosing a photograph to illustrate nature's mastery of camouflage, I have to be careful to use one you can actually see! writes George Hogg (Hogg Estate Services).

I think you might just manage to spot the moth in this picture.

It is a Grey Chi, a moth which evolution has designed to hide upon lichen encrusted bark and rock.

Before you credit me with the eyesight of a kestrel for spotting the creature, I will admit to placing it there myself to show how well the patterns match.

We tend to think of evolution taking millenia to produce its magic.

In fact, evolution is going on all the time and can in some cases produce changes in just a few generations of certain species.

An oft quoted example is the Peppered Moth, which occurs in both dark and light forms.

During the industrial revolution when city buildings and even tree trunks and branches were blackened by smoke pollution,the dark form of the moth proliferated.

As we cleaned up our cities in later years, the light form once again proliferated.

Quite simply those which are hidden from predators on sooty surfaces are more likely to survive in dirty cities and those camouflaged on clean stone surfaces do better in clean cities.

This is just one of many examples of speeded up evolution.

Regarding my photograph of a moth on an old stone wall. It is typical of the roosting places in which individual moths will spend the daylight hours.

Each one seems to know exactly which type of bark, stone, lichen or moss matches its own particular wing and body pattern.

Knowing this you would think it would be easy enough to spot day roosting moths. Trust me, it is almost impossible.