What were Tree-ear and Crane -man named after?

From the text:

Tree-ear was so called after the mushroom that grew in wrinkled half- circles on dead or fallen tree trunks, emerging from the rotten wood without benefit of parent seed.

Tree-ear knew the story of his friend’s name. "When they saw my leg at birth, it was thought I would not survive," Crane-man had said. "Then, as I went through life on one leg, it was said that I was like a crane.