I think the Yorkshire Terrier changes more than any other breed of dog.
Buddy has changed so many times he's like a camielion.

His beautiful black body is no long black unless I shave it down then he's like black velvet. We are growing in his coat once again over the winter
and the color looks like a mud puddle! Little brown, little silver and some
faded black all mixed in. His copper muzzle, head ,feet and belly remain bright in color. He's going on 5 so I hope this is it.