Adaptation is the most basic and rather self-evident concept. It is the morphological or physiological modification in an organism to adjust itself in a particular environment. In some animals, it is known as mimicry as for example praying mantis or stick insect. The stick insect or praying mantis having green body colour exhibits close resemblance with twigs and foliages. It is a type of protective mimicry. They exhibit close resemblances also with the twigs in having slender body, attenuated limbs, sympathetic colouration and slow movement.