Appreciating the subtle and not so subtle physical differences between individuals or subspecies of animals. I'm not an expert, just a person who likes to troll through the internet to find interesting looking animals. Feel free to point out any mistakes. I am not accepting requests at the moment. I do not claim to own any pictures, and will try to link back to the source.
Barn Owl (Tyto alba) 
  1. An average and melanistic pair. Instead of pure black, this lovely bird is a mix of buff, grey, and charcoal-black.
  2. Two different subspecies found in the Netherlands, the lighter male is T.a. alba and the dark female is  T. a. guttata. The male has a white belly free of spots and the border around his facial disk is incomplete. Interestingly (at least I find it interesting), even though the feathers are white, you can still make out the heart shape. The female is a rusty color all over, with a spotted belly, and buff highlights to her eyes.
  3. This Galapagos barn owl (T. a. punctatissma), has a creamy buff facial disk with a bi-colored boarder, line dividing it’s face, and a white spotted belly.
  4. I’m not sure what subspecies this is, but this individual is very pale. The disk boarder is almost absent, the rusty color is greatly reduced, leaving the speckles on the head to really pop out.
  5. Very unique markings on this one from Georgia, US! It’s disk is divided in half by a bold, thick black line, and the lower border is as well. A white speckled belly and what seems to be very dark wings really make this dude pop. And he’s waving to the camera, too!
  6. Another unique individual with a dark stripe, although much thinner. It’s grey belly is patched with buff and spotted. It’s rusty head and “tear stained” eyes really pop out against his grey disk. He may not be pretty, but he looks like someone you wouldn’t want to meet in a dark alley.