Mandatory hunter: the animal.

‘Unting is all that's worth living for – all time is lost wot is not spent in ‘unting – it is like the hair we breathe – if we have it not we die – it's the sport of kings. The most vital possessions of the plant are the chloroplasts in the cells of its leaves. Through these, the organism can convert, for its own purposes, a fraction of the solar energy that falls upon it. Sunlight is remarkably uniform in its intensity, and a plant has little to gain by moving about. It can thus afford a relatively stationary existence, the only motion being that required to reach regions beyond the shade of its immediate environment and its competitors. Because they have no chloroplast-bearing cells, animals have paid the penalty of having to develop several specialized functions in order to satisfy their energy requirements. They must have a means of locomotion and feeding, and some form of coordination of these faculties, however primitive, is needed. And as insurance against the unsuccessful forage, they should be able to store digested energy. Moreover, unless an animal is so small that the normal process of diffusion is adequate, it must have a circulatory system to distribute dissolved gases and chemical compounds to its various parts. [ABSTRACT FROM AUTHOR]

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