Good topic. I find it interesting the many different patterns Browns may have. I have no science to add to this thread but here are a few Browns with interesting markings all from my favorite local river.

A pretty standard brown from this river to start out for a baseline.



Some have almost no spots...



...Some have so many it's ridiculous.



Large Spots



A few have that marbled pattern that Kelly mentioned, like a Tiger Trout, although on the river I fish it is usually only around their head and gill plate if they have it at all. Much more subtle than the pic Kelly posted.


When it comes to Browns, some got hit flush with the ugly stick, although with the top fish it has nothing to do with his markings...

(Old Snaggle Tooth)

(The slug)

...And some are just too pretty for words.



The one thing I do know, no matter the markings, they are all fun to match wits with.