Animals.
Archimandrite Nikifor’s Biblical Encyclopedia
The animals of the Bible were divided into four classes: land-dwelling animals, both the larger and smaller four-footed beasts (Lev. 11:2), fish of the sea (vv. 9, 10), fowls of the air (v. 13), and creeping things (vv. 20, 29, 41). Within these classes a further distinction was made between the clean, which might be used for food, and the unclean, which were not permitted to be eaten (Lev. 11; Deut. 14). The division of animals into clean and unclean existed even before the Flood.
In the book of Genesis (7:2) we read that God commanded Noah to bring into the ark seven pairs of every clean beast, and two of every unclean beast. Fuller details concerning clean and unclean animals are given in the book of Leviticus (ch. 11 [as given]). Of the land-dwelling animals (both domestic and wild), those with a divided hoof and that chew the cud were reckoned clean, such as: oxen, cows, sheep, goats; while all others lacking these characteristics, or lacking one of them, were unclean, such as: donkeys, camels, and others.
Of the wild animals, the following were eaten and reckoned clean: deer, gazelles, wild ox [bison], hind, and others (Deut. 14:5); unclean were: the hare, the jerboa, the hedgehog, the pig, and all beasts of prey. Of the creatures living in the water, all those having fins and scales were reckoned clean and fit for food; Holy Scripture, however, gives no names for specific kinds of fish. Among birds, unclean were reckoned the birds of prey, such as: ravens, eagles, kites, falcons, hawks, storks, and others (Lev. 11:13–19; Deut. 14:12–18).