12 Facts About the Human Body Scientists Still Scratch Their Heads About

So many things about humans are taken for granted, one of them being our fingerprints. But surprisingly, not everyone has formed prints on their fingers, which makes life a bit hard for them. So it’s only natural that we wonder how this is possible and ask scientists for an explanation. Unfortunately, for some things in life, science has only guesses to give us in lieu of clear answers.

Bright Side would like to shed some light on 12 human traits and abilities that we have yet to find a scientific explanation for.

1. How someone can stay without oxygen for 20 minutes

According to scientists, 30-180 seconds without oxygen can make you lose consciousness. After 3 minutes, the brain starts getting damaged, and at 10 minutes, a coma should be expected. However, there are training methods that allow the brain to survive without oxygen for longer periods of time.

More specifically, Budimir Buda Sobat broke a world record by staying underwater for 24 minutes and 33 seconds. He surpassed Aleix Segura’s previous record by 30 seconds. The only thing both of them did before going underwater was breathing pure oxygen for a few minutes.

2. How someone can stay awake for 11 days

In 1963, a 17-year-old boy named Randy Gardner managed to stay awake for 11 days and 25 minutes. A sleep researcher was with him the whole time monitoring how his cognitive abilities were affected. The young boy was staying active by playing basketball, while those around him made sure he wouldn’t doze off. During the 11 days, his sense of smell and taste were affected greatly.

Scientists have yet to perform thorough research on how a human can stay awake for days on end without experiencing any of the very serious consequences of sleep deprivation. And the reason for this is probably because the term “awake” is not something specific. Someone can have their eyes open, but their brain might be completely shut down.

3. The number of days a person can go without water

The general rule says that humans can stay without water for up to 3 days. However, this depends on various factors, such as age, physical activity, and overall health. Also, if your diet consists of many watery foods, such as fruits and vegetables, then your sources of water expand.

In 1979, a man by the name of Andreas Mihavecz survived without water for 18 days straight. He was kept in a police cell and the guards responsible had completely forgotten about him. The way he managed to stay hydrated was by licking the condensation from his cell walls. This is truly spectacular if you think about the fact that he wasn’t receiving food either.

4. Why we need our appendix

The appendix is one of the organs that gets removed very often from the human body. That’s one reason many scientists used to believe that it served no purpose. However, according to biologist Heather Smith, 533 species of mammals have an appendix, a fact that proves its importance. More specifically, an appendix protects our immune system.

The way it works is by hosting many “good” microbes that the body uses when affected by an illness. However, there is no evidence that those who have removed their appendix will be more susceptible to illness. So, the bottom line is that we have some knowledge of the use of the appendix in our bodies. But more detailed studies need to be made in order to understand the complexity of the organ.

5. Why we have dominant hands

About 85% of humans are born with their right hands being dominant. One theory for that occurrence is that the left hemisphere of our brain controls our speech and movement abilities. It also controls the movement of our right hand, which makes the majority of us right-handed. Another theory says that right-handedness goes back to the first humans on Earth and their use of tools.

Even 2 million years ago, humans were predominantly right-handed, and that’s why all their tools were made to accommodate that tendency. A small percentage of left-handed people are said to have existed, and they would have been given an advantage in combat. If your enemy expects you to hit them with your right hand but you hit him with your left, then you’re more likely to win.

6. What makes us yawn

Until very recently, many people believed that yawning brought more oxygen to the brain, but that was proven to be wrong. One very popular theory is that by yawning, the brain tries to wake itself up. It also brings the temperature down if our bodies get warmer than normal. However, this small study can’t be made fact for sure since it only examined 120 humans.

Another theory says that yawning has an important social meaning. When someone starts yawning after their friend does, it means that their social competence and empathy are very evolved. Also, in many cultures, people still believe that yawning is a sign of tiredness. At the end of the day, the scientific community can’t agree on what causes us to yawn.

7. Why only women have breasts and not men

In the world of primates, females tend to form breasts only after they give birth and so that they can feed their babies. However, humans are the only beings that have fully-formed breasts for their entire lives. One explanation is that women form full chests as a sign that they’re ready to become mothers and feed their babies. That’s why they aren’t born with fully developed breasts.

Another theory holds the same narrative by saying that women need to store fat and, therefore, energy. They use their chests and hips for that reason so that they can feed their babies. And since men aren’t able to give birth, they never needed to go through that same evolutionary process.

8. What causes us to experience hypnic jerk

Right before sleep sets in, you may experience a moment where you feel like you’re falling from the stairs or off a cliff. You suddenly come into some form of consciousness from the sudden movement of your legs. However, you might not fully wake up. And as researchers say, about 70% of us have experienced this at least once in our lifetime.

There is no definite explanation as to why this phenomenon occurs, although there are a few theories. Some of them include stress and anxiety, exercise before bedtime, sleep deprivation, or the consumption of caffeine and nicotine. Also, some researchers suggest that primates developed this phenomenon as a skill so that they wouldn’t sleep in dangerous positions.

9. Why some people sneeze at the sight of the sun

The photic sneeze is not a super common occurrence, but people who experience it have most likely inherited it. However, no one knows just yet which gene is responsible for this sneezing. What we do know is that most people will sneeze at least 2 or more times, with extreme cases reporting up to 40 sneezes. One theory suggests that a change in light could irritate the nose and, therefore, trigger a sneeze.

Another theory says that exposure to sunlight causes the eyes to tear up, and as a result, the nose gets annoyed too. The same thing can happen if you try to use eye drops or have just eaten spicy foods. Unfortunately, there aren’t many medications that can treat this unusual reflex.

10. Why some people don’t have fingerprints

Adermatoglyphia is a condition where some people are born without any fingerprints. It’s also known as “immigration delay disease” since those who have it have trouble entering the borders of foreign countries. It’s a very rare condition and only a few families have been diagnosed around the world.

It has been found through research that the condition appears due to a small mutation in a person’s DNA. However, what is still puzzling is how and why this mutation happens since a person forms fingerprints while in the womb.

11. Why laughter is contagious

Most of us have experienced laughing just because someone next to us was giggling and not because we heard something funny. The first theory is that by hearing someone laughing, endorphins are released in a specific area in our brains. The more receptors someone has, the more endorphins it will receive, making them laugh more.

The second theory established a connection between contagious laughter and psychopathy. It suggests that boys who don’t join in the laughter with those around them are likely to develop psychopathic behavior.

12. How someone can starve for over a year

In 1966, Angus Barbieri had gone without eating solid food for 382 days, losing a total of 260 pounds. He was monitored by doctors during the whole process and only consumed tea, coffee, water, and some vitamins. The only things that he added to his diet during its completion were some sugar and milk in his tea.

While starving for so long seems impossible, the body seems to be able to find an alternative to food. Scientists explain that after 8-12 hours without food, our bodies start using the glucose and amino acids stored to gain energy. So the answer to the initial question is complicated since someone’s weight plays a huge part in the result. A very overweight person will more likely survive for longer without food than a very thin person.

Which one of the facts above shocked you the most? Wouldn’t it be surprising if men had developed chests as well?