The similarity I referred to between the bear and the elephant skull has to do neither with the shape nor the size of the skulls, but in the difficulty of locating the brain within a massive head for a fast shot. I think you know this and are just trying to be difficult. Had your bear skull photo been face on, it would have illustrated the narrowness of the brain pan vs, the overall width of the skull. Add to this the fact that the bear's head could be in motion, unless he's locked onto you, a mixed blessing, adds to the degree of difficulty faced by the rifleman.
Here's a few face on photos of live bears which should help illustrate the problem . . .
In each case the eye sockets are outside the width of the brain pan, and depending on the shot angle, sometimes there isn't much to shoot at. It appears that the brain should extend to the base of the ears, but it doesn't.
If you spend a few hours on an airplane and get to face down one of these things, the trick they say is to imagine sliding a broom stick through the ears then attempt to break the center of the stick with your shot. By the time you're done trying to figure that one out, you're a smudge on the ground. The problem with the elephant is the same as the problem with the bear; finding an index to the brain inside a confusingly large head.