Open Question: Why do cockatiels have a strange foot fetish?

[feedcrawler]

I know of many accounts of it, and my bird does it. If he is by my feet, or I move/wiggle any part of my feet with or without whistling, he will always try to interact with it. I know they are curious and somewhat mischievous birds, but sometimes it comes out of nowhere and is quite funny. But alas, I have no idea why he squawks, squeaks and does some little, puffed-up mock charging around my foot. Also, even if I have shoes on, he does it. So I do know it probably isn't only my toes. It's adorable, but I can't help but wonder why in the world he/other tiels do it.

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