Peregrine Took

If you see Peregrine Took today you might think he's black, but he's not. He's a fun example of age progression of sooty and shade. He was privately bred and was born in 2009. My friend Matt helped foal him out and named him. He took the first two pictures.
As a foal Pippin was a pretty normal looking bay tobiano foal. The first photo is when he was a newborn. The second was when he was a little older and he'd lightened up in the sun.

The third photo is when Pippin was a yearling. His head has gotten dark but can still see the bay on his back.

The last two are from this past January. Look how dark he is! Can hardly see any of his brown. I took the headshot specifically because you can see in it that his nose is still brown. If he wasn't a pinto with such distinctive markings you'd almost think he was a completely different pony from the foal.

Looking at Pippin's pedigree this dramatic color shift makes sense. His sire is Tuffer Than Leather who sired multiple sooty ponies, and is the ancestor of more thanks to his daughter Baybe. Interestingly Pippin looked pretty similar to his sire as a foal and as an adult. So it appears father and son went through a similar color shift as they aged. Pippin's dam Zebie Beebe Bella was also a sooty buckskin, you can see her behind him in the newborn photo.

Sooty and color shade can't be tested for but you can see in Pippin how it's probably genetic in some way. I really hope someone figures it out in my lifetime!
https://www.thecolorfulchincoteague.com/sooty.html
https://www.thecolorfulchincoteague.com/colorshade.html