What is the connection between shrimp and old age?

Question

Shrimp(えび) is written several different ways in Japanese. For example, there are the words commonly used in Chinese: 蝦 and 鰕. There is also a compound specific to Japan, 海老, and a kokuji, 蛯. Both of the latter contain the character for old age, 老. Is there some reason why the Japanese associate shrimp with old age?

Answer 1

The Japanese Wikipedia page for エビ says the following:

漢字表記の「海老」や「蛯」の字は曲がった腰を老人に見立てたものである。

Apparently the use of 老 comes from the way shrimp bend forward, like an old person bending forward at the waist.