CHAPTER TWO

THEORIES OF EVOLUTION

Traditional biology

The first biology books were written about 2400 years ago by Hippocrates and Aristotle, and in those volumes we find not only a detailed account of all that was known at the time, but also a grand attempt to build a comprehensive view of nature. It is still debated if those books can be regarded as the starting point of biology, but it is certainly true that they were the end result of a long oral tradition whose origins were lost in the night of prehistory.
The plants and the animals of agricultural civilization had been produced by a collective experiment which lasted thousands of years, and all the results obtained by farmers and breeders were leading to a precise general conclusion: it is possible to produce new varieties of plants and animals, but it has never been possible to produce new species. This was the meaning of the popular (and apparently naive) statement that “daises only come from daises and elephants only from elephants”.
Aristotle’s writings on anatomy, physiology and animal behaviour show that he had many contacts with breeders, farmers and fishermen, and perhaps it was their testimony that made him reject the historical transformation of organisms, an idea that was fashionable in his times and that even Plato had accepted (as a continuous degeneration).
Eventually, however, the conclusion that “species are immutable” did prevail, and even received a religious blessing, but it would be wrong to forget that its real basis was the millennial experience of farmers.
The weight of this idea comes from its consequences.