Form and Function: A Contribution to the History of Animal Morphology

by E. S. Russell

CHAPTER II

COMPARATIVE ANATOMY BEFORE CUVIER

For two thousand years after Aristotle little advance was made upon his comparative anatomy. Knowledge of the human body was increased not long after his death by Herophilus and Erasistratus, but not even Galen more than four centuries later made any essential additions to Aristotle's anatomy.

During the Middle Ages, particularly after the introduction to Europe in the 13th century of the Arab texts and commentaries, Aristotle dominated men's thoughts of Nature. The commentary of Albertus Magnus, based upon that of Avicenna, did much to impose Aristotle upon the learned world. Albertus seems to have contented himself with following closely in the footsteps of his master. There are noted, however, by Bonnier certain improvements made by Albertus on Aristotle's view of the seriation of living things. "He is the first," writes Bonnier, "to take the correct view that fungi are lower plants allied to the most lowly organised animals. From this point there start, for Albertus Magnus, two series of living creatures, and he regards the plant series as culminating in the trees which have well-developed flowers."[9]

Aristotle's influence is predominant also in the work of Edward Wotton (1492-1555), who in his book De differentiis animalium adopted a classification similar to that proposed by Aristotle. He too laid stress upon the gradation shown from the lower to the higher forms.

In the 16th century, two groups of men helped to lay foundations for a future science of comparative anatomy—the great Italian anatomists Vesalius, Fallopius and Fabricius, and the first systematists (though their "systems" were little more than catalogues) Rondeletius, Aldrovandus and Gesner.

The anatomists, however, took little interest in problems of pure morphology; the anatomy of the human body was for them simply the necessary preliminary of the discovery of the functions of the parts—they were quite as much physiologists as anatomists.

One of them, Fabricius, made observations on the development of the chick (1615). Harvey, who was a pupil of Fabricius, likewise published an account of the embryology of the chick.[10] In his philosophy and habit of thought Harvey was a follower of Aristotle. It is worth noting that in his Exercitationes anatomicae de motu cordis (1628) there is a passage which dimly foreshadows the law of recapitulation in development which later had so much vogue.[11]

A stimulating contribution to comparative anatomy was made by Belon,[12] who published in 1555 a Histoire de la nature des Oyseaux, in which he showed opposite one another a skeleton of a bird and of a mammal, giving the same names to homologous bones. The anatomy of animals other than man was indeed not altogether neglected at this time. Coiter (1535-1600) studied the anatomy of Vertebrates, discovering among other things the fibrous structure of the brain. Carlo Ruini of Bologna wrote in 1598 a book on the anatomy of the horse.[13] Somewhat later Severino, professor at Naples, dissected many animals and came to the conclusion that they were built upon the same plan as man.[14] Willis, of Oxford and London, in his Cerebri Anatome (1659) recognised the necessity for comparative study of the structure of the brain. He found out that the brain of man is very like that of other mammals, the brain of birds, on the contrary, like that of fishes![15] He described the anatomy of the oyster and the crayfish. He had, however, not much feeling for morphology.