Owls: the black sheep of the raptor "family", stealth predators known for their funny habit of twisting their heads backwards and filling the night sky with hoots. More specifically, they are characterized by their unique feather structure adapted for silent flight and their incredibly powerful eyes, which can hardly be called eyeballs. Their eyes are actually quite elongated in order to fit more cone cells and allow for extremely powerful eyesight. Problem: this means they cannot actually turn their eyes, meaning they need to turn their head to the side in order to see things not directly in their field of view. Thus, they evolved twice as many vertebrae (small spinal bones) in the neck as humans (and even giraffes), with 14 compared to our measly 7, in order to allow them to fully turn their heads backwards. With all these adaptations, there's a common rule of thumb among bird watchers. If you see an owl in the wild, chances are it's already seen you.