How do you tell groups of animals apart?

For each pair of groups on the card, name the trait that separates them. Then ask whether the same trait would still separate them in the classification your class uses.

Read al-Jahiz's own sorting. Before the kinds of animals, he sets out a division of the world: bodies are alike, different or opposed, and in sum inanimate or growing; the growing are animals and plants; animals walk, fly, swim or creep; and those that walk are humans, beasts, predators and vermin ². He then divides birds into predators, grazers and swarming insects, and notes that not everything that flies on two wings is a bird: locusts, bees and flies fly but are not called birds; the bat is reckoned among birds though featherless, the ostrich has feathers but is not a bird, and not everything that swims is a fish ^3 4 5. The record of Kitab al-Hayawan has the passage in full.

Al-Jahiz says what he is following. In this division he follows the names established and known among the people of this language, singling out what they single out and grouping what they group ³. The record gives no other reason for the division in his words.

A reader may take this passage for a zoology handbook. The editor, Muhammad Basil 'Uyun al-Sud, says the title suggests a book confined to animals, while it contains sciences and learning larger than its title, so that in his words it is "a collection of books gathered in one book" ^6 7. The sorting of animals is one part of a book that also holds a picture of the Abbasid age with its culture and customs, and the features of many lands ⁶.

The passage reaches us through a modern edition, so ask whose words you are reading. The editor says the book had been printed more than once and that, for all its printings, it suffers from omissions and faults ⁸. He added what he found missing between brackets, his main aid being the Thimar al-Qulub of al-Tha'alibi ^8 7. He also added numbered sub-headings in square brackets drawn from al-Jahiz's own words, and left al-Jahiz's headings unbracketed ⁷. The edition is the second printing of Dar al-Kutub al-'Ilmiyya, Beirut (1424 AH / 2003) ⁹.

Al-Jahiz says he follows the names people already use, and that the bat is reckoned among birds though featherless ^3 4. Take a position and answer the strongest objection to it: should a classification follow the names people already use, or a trait that anyone can check, and why?

• Kitab al-Hayawan: the division of beings, the chapters of the seven parts and the edition.
• al-Jahiz: the author, as the editor's extract from Shadharat al-Dhahab presents him.
• al-Tha'alibi: the author whose Thimar al-Qulub helped the editor fill gaps in the text.