Limbal rings and the parakeet's nose...

I am old.  This means I have seen a lot of life, and being naturally curious, I have accumulated a fair amount of useless knowledge.  A professor I remember from college, 56 years ago, put a big K on the blackboard, then circled it and wrote a bunch of I;s around it.  This, he said, is your knowledge.  And all around it your ignorance.  Then he did the same thing with an even bigger K.  So, the more you know, the more you know you don't know.  Personally, I love learning.  I went back to college a decade ago, and learned even more, some of which I wish I didn't know, like the Yellowstone caldera just waiting to annihilate us. Anyway, I learned recently about limbal rings, the dark circles some of us have around the iris of the eye.  They are apparently preferable, and there is talk of making contacts that have them.  Mine are interesting.  They have not faded away, as some are wont to do, but instead are more prominent, and dark blue!  Yes, blue rings around my brown eyes.  Well, not really brown, more of a honey color.  Okay, I am weird.  And then there is the parakeet's nose, that little colored cuff where the nostrils are.  It's call a cere, and when it is blue, that means the bird is male.  There, now you know what I have floating around in my head.