#9. What is dark matter?
Aside from the obvious fact that it is pretty dark, we have no clue what dark matter is. Scientists came to the conclusion that dark matter exist, because without it, nothing in the universe that we observe will be this way. So they have stated that about 27% of all the matter in the universe is dark matter. Ask them what dark matter is, and you will get a hour long explanation which in short mean “we don’t know”.
It is called dark matter, because it doesn’t emit or reflect any light, and we still have no way of detecting or observing it. Some have speculated that dark matter is made up of Weakly Interacting Massive Particles (yep, that’s right – WIMP) which theoretically are about a hundred times bigger than a proton. But until we get our hands on that stuff we can’t be certain of anything.
Actually scientists are not sure if dark matter exists at all. They just came up with that name to label something that is needed to make their equations work in representing the observable models in the universe.
#10. Why do we have different blood types?
Blood transfusion is a modern day miracle, and you can’t help but wonder why haven’t we thought of that before. The fact is that people have attempted blood transfusion even in ancient times, but they couldn’t figure out why it sometimes worked and sometimes was complete disaster.
It was only after we discovered the blood types, that we found a way for safe blood transfusion. But that also brought another question – “why do we have different blood types”? I bet you won’t be surprised if I told you that no one knows.
We learned quite a lot about the different blood types. We know that certain types are more susceptible to some infections and diseases than others. We also learned how the parent’s blood types determine the offspring’s type. Learning all this useful stuff made us ignore the reason for the existence of the blood types.
#11. Why do we yawn?
One thing that is for sure is, that if you yawned while reading this article it is definitely not a sign of boredom. I mean there is no chance that someone could get bored from this great article!
Yawning as an involuntary action observed in many mammals. It has puzzled people for centuries. Perhaps the most intriguing observation is that is seems to be contagious. You can make another person or even animal yawn by simply yawning yourself in front of them. Now isn’t that neat?
But why do we do it? One of the earliest attempts to provide an explanation stated that this is the body’s way to increase the oxygen levels in the blood when it needs to. Modern day research however has concluded that a yawn actually lowers the oxygen levels. Another shot at this claimed that it is a way for the body to get rid of excess heat in the brain. Sadly enough, statistics show that the rate of occurrence is lower at warmer temperatures.
To this day we can do nothing to explain this mystery. Nothing but to yawn. And if you do yawn, just remember, that this is not due to this article being boring. That can not be proven just like all the other theories.