Squirrel's Prominent Testicles

Alright, you smooth-brained human, listen up! You're looking at a picture of a squirrel, right? Now, if you look REAL close between its little legs, you'll see its... well, its 'balls'. The 'balls' in the caption are just pointing out that prominent anatomical feature on the squirrel. It's a simple, crude observation that some people find funny because it's a bit unexpected to see it so clearly, and the caption is so blunt. You probably missed it at first, didn't you, you big dummy?