Well, I'm not sure where or by whom this question was first sent to AJ, but I've had a good laugh researching a plausable answer:

An average healthy human can expect to go through life's four main body cycles:

Young - Young Adult - Adult - Mature Adult

Probably the peak age for fitness is between 19 and 34 depending on lifestyle.

Ears will tend to grow in proportion to the body. However, from the age of 45 - 55 onwards most people start to gradually shrink from their full size. Nobody is quite sure why, although some scientists suspect there might be an aging gene that determines this process.

The Odd Thing About Ears



It seems that ears are unaffected by the aging process; in fact, rather than shrinking, ears tend to start a new spurt of growth.

Many theories have been advanced as to why this should happen.

One of the most plausible is the "natural hearing aid" theory.

As people get older hearing loss can be a big problem. However, the human body may conteract this by making the ears bigger to catch more sound. Again there's probably an "ear growth" gene that gets switched on in old age.

I know... this may sound like a bad April Fools joke.

You do a search on Google and see if you can come up with a better answer

http://faculty.washington.edu/chudler/qa0.html#q98

Quote: "As people age, their ears get larger. Ear circumference increases an average of 0.51 millimeters per year."

Jack