Gurus

One of the reincarnations of Lord Vishnu, Lord Dattatreya, observed that he considers aa guru any person, animal or thing which taught him anything.The 24 Gurus in Lords list are earth, air, sky or ether, water, fire, sun, moon, python, pigeons, sea, moth, bee, bull elephant, bear, deer, fish, osprey, a child, a maiden, a courtesan, a blacksmith, serpent, spider, and wasp.
Each of the above teaches him something.

Arun Shroff tells us of some more Gurus below.