What are the 8 types of Valuable Colours?

They are of direct physiological need. According to Lull (1952) they are of following 8 types according to their use.

1. Cryptic or sympathetic colours.

2. Warning colours

3. Alluring colours

4. Mimetic colours

5. Signal marks

6. Recognition marks

7. Confusing marks

8. Sexual colours.

1. Cryptic Colouration

The hue of the animal harmonizes with its surroundings in such a way that is blends into the back ground and loses its conspicuousness. It may lie for its own protection from it enemies (Protective colouration) or to lie in wait for its prey long enough to permit a kill (Aggressive colouration).

Examples of protective colouration are seen in the arctic hare and northern weasels which grow a coat of white fur in the fall, then revert to a brown coat in the spring.

Then, there are numerous cases of stick and leaf insects which look like parts of the plants when they rest on them. Thus, the stick insect (Clonopsis gallica) looks like a piece of a dry twig of grass and in the leaf butterfly Kallima the wings are quite similar to leaves of tree on which it lives.

Caterpillar of geomatrid moth looks like a twig when it rests on the branches of plants. Many moths have a close resemblance to the bark of the trees when resting on them. The best example is that of peppered moth (Biston betularia).

2. Warning or Revealing Colours

They are conspicuously red and yellow found on the bodies of poisonous or unpalatable animals. This type of colouration is the result of natural selection and is due to abundant deposition of a waste-matter pigment. Examples of warning colouration are numerous.

The porcupine, tiger and lion among mammals, coral snakes and gila monster among reptiles, tiger-salamander among amphibian, bees and wasps among insects. Warning colouration also carries with it the acquiring of such attitude, which produces terror. For example, spreading of hood of the ‘spectacled cobra . Amphibia in general are cryptically coloured but Triturus torosus is well supplied with poisonous skin glands and hence may be said to show aposematic colouration.

3. Alluring Colours

In this colouration the animal resembles like its surrounding to allure their prey. These colours are not cryptic but sympathetic. For example certain spiders resemble like an orchid blossom, in colour and shape.

4. Mimetic Colours

It is a colour resemblance between an animal and any other object animate or inanimate. It is either for conceal or it may be warning colouration. In warning colouration, it is a ‘bluff’ of highly defense value.

5. Signal Marks

The signal marks and apparently of very great importance among gregarious animals where mutual aid in time of danger is a characteristic. For example in the cottontail rabbit, Lepus syluaticus, the movement of tail exhibited to its young ones shows them the way to safety. Thus the signal is instantaneous, which may be of vital importance to the safety of the individuals.

6. Recognition Marks

These are for the use of other individuals of the same species. These recognition marks are borne by many insects and are often, as in many butterflies and moths, visible only when the animal is in motion, for then no amount of protective colouration will generally avail its owner.

7. Confusing Colouration

In this type of colouration, animals may have conspicuous colour but its brilliant colour disappears for harmonizing with the background, where they rest; for example, in various moths and butterflies. It is also found in somber-coloured lizards.

8. Sexual Colouration

It has been seen that the males of birds and other forms are often much more conspicuously coloured than their females. Why the males are conspicuous is perhaps not so clear, but the protective colouration of females must be of prime importance to the race, especially if she is nesting or a potential mother. The young males, which do not attain sexual maturity, are also protectively coloured.