Do you see what I don't see

[Steven Sweeney]

Whoa, check this out:
YouTube Boxer

Freeze it at about 23 seconds and you'll get a VERY good idea of what you're dealing with here.

It may be that just lightening the value of the dark perimeter form will do the trick.

We're kind of sidling over into the "pet portrait" area, so that's probably about all I'll say about this, except that the matter of cropping ears and docking tails is extremely controversial, the practice being largely a "show dog" thing, so that's probably why you found relatively fewer images of "natural" ears.