Many Labrador Retrievers are genetically wired to be hungry. A 2016 University of Cambridge study found that about 23% of Labs carry a mutation in the POMC gene that disrupts their sense of fullness. That helps explain why Labs are famous for begging and prone to obesity.
A German Shepherd's nose has about 225 million scent receptors, compared with roughly 5 million in a human. That huge difference is why they excel at tracking and detection work.
Beagles have about 220 million scent receptors in their noses, which makes them among the best sniffers in the dog world and explains why they're always following their noses.
The Maine Coon became Maine's official state cat in 1985, which makes sense for a breed that developed naturally in the state's harsh New England winters.
Elephants communicate with low rumbles called infrasound, which are too low for humans to hear and can travel for miles. They may even sense these vibrations through their feet.
Sharks have special organs called ampullae of Lorenzini that detect the tiny electric fields produced by other animals' muscles, which helps them find hidden prey.
Snakes flick their tongues to collect scent particles from the air and deliver them to the Jacobson's organ in the roof of the mouth, which basically lets them smell with their tongues.
Pit vipers, like rattlesnakes, have heat-sensing pits on their faces that detect infrared radiation, so they can "see" the body heat of warm prey in total darkness.