26 Comments That Turned A Simple Anatomy Question Into Internet Gold

There are some truly hilarious gems on this thread, but jokes aside, there is a reason that we have two small "noseholes" instead of one big one. As the Popular Science website puts it, "Our nostrils share the workload like coworkers on rotation."

Each nostril has a mind of its own, if you will. They behave differently to each other throughout the day. "This is known as the nasal cycle," explains the site. "And it plays a vital role in our overall health. At a certain point, one nostril takes in air more rapidly. Later the dominant nostril shifts. Throughout the day, which nostril is dominant keeps swapping."

This alternating cycle, say experts, helps us to breathe and smell better.

“The fact that we have two nostrils is not unusual, as we have two eyes and two ears,” says Ronald Eccles, an emeritus professor at Cardiff University, and the founder of its Common Cold Centre. “What is unusual is that the nostrils alternate airflow from one side to the other. This may allow one side of the nose to rest.” 

Our noses do a lot more than we might realize. They draw air into and out of the lungs, and they also prepare the incoming air. The nose does this by filtering out dust and pollutants, warming the air so that it's at body temperature. In addition, the nose moistens the air before it gets to our lungs, making sure that it's at 100 percent humidity.

Without this process, note Popular Science's experts, the air would be colder and drier. This can irritate and constrict our airways and lead to inflammation.

While our nostrils each 'stand alone' on the outside, they lead into the same nasal cavity inside. According to U.K.-based sinus and nose surgery specialists Septal Perforation, the nasal septum plays an vital role in keeping the balance between the two nostrils.

"While this septum separates them, the air you breathe is distributed across both nostrils and into the larger nasal cavity, which is a shared space," notes the site. "The nasal cavity itself is connected to the sinuses, a series of air-filled spaces in the skull that help filter and humidify the air you breathe."

Just like many of us have a dominant hand, so too do we have a dominant nostril. This means that the one works harder than the other. However, our nostrils naturally switch between a dominant nostril for airflow throughout the day - a process known as the nasal cycle.

Head-and-neck doctor at the Cleveland Clinic Dr. Michael Benninger says that at any given time, people do about 75% of their breathing from one nostril and 25% from the other. According to a study published in the PLOS One journal, right-handed people tend to spend more time favoring their left nostril.

While some are wondering why we have two nostrils instead of one big "nose hole," others may be pondering the point of two eyes when we only see one image. According to experts, two eyes provide us with stereo vision and depth perception. This is because the muscles that control our eyes automatically focus both eyes on the same spot and the brain fuses the images.

"Our brain is able to put two images together and make them a single image," explains the Aloha Laser Vision site. "Having two eyes helps us figure out how far away something is. Our eyes need to focus, or point themselves in certain ways, differently in order to see things at different distances."

It adds that our eyes can point straight forward to see something very far away, but they have to slightly turn toward each other to see things really close. "The different focuses help our brain figure out what is far away and what is really close," say the vision experts.