Dogs can be heroes, too.
You probably won't find any actual seals hanging out with the prestigious U.S. Navy SEALs, but you might find a few war dogs. Take, for example, Cairo, a Belgian Malinois like the one pictured here. He was part of the 81-member SEAL DevGru unit responsible for taking out Osama bin Laden.
The dogs undergo rigorous training, and they even parachute in with their human co-fighters!
Image: ©Mark Raycroft/Minden Pictures/Corbis