This section is from the book "The Human Body: An Elementary Text-Book Of Anatomy, Physiology, And Hygiene", by H. Newell Martin. Also available from Amazon: The Human Body.
In a tribe of wandering savages, living by the chase, we find that each man has no special occupation of his own; he collects his own food, provides his own shelter, defends himself from wild beasts and his fellow-men. In a civilized nation, on the contrary, we find that most men have some one particular business: farmers raise crops and cattle; cooks prepare food; tailors make clothes; and policemen and soldiers protect the property and lives of the rest of the community; in other words, we find a division of labor. Just as the more minute the division of employments in it is, the more advanced a nation is in civilization, so an animal is higher or lower just as the duties necessary for maintaining its existence are distributed among different tissues and organs. In the lowest animals every cell is concerned in feeling, and moving, and catching food, and digesting, and breathing; in higher animals different cells are set apart in different organs for the execution of each of these separate functions.
What determines the form of an organ ? What its faculties ? Give examples of the employment of cells with different powers to do different things. What is Anatomy really ? What Physiology ?
Explain what is meant by the physiological division of labor. In what class of nations is the division most minute ? What decides whether an animal is higher or lower than another ?