The world was transformed by the Scientific Revolution, an age that began at the end of the Renaissance in Europe. During this time, scientific discoveries gave birth to a new way of thinking, which lessened the power of religion in individuals’ lives. The publication of Nicolaus Copernicus’ “On the Revolutions of the Heavenly Spheres” in 1543 and Isaac Newton’s “Principia” in 1687 bookend the period. Ever since then, humanity has progressively relied more and more on science (and not religion) to explain the world around us and our own bodies. However, there are plenty of simple questions which are still unanswered by science. Here is a list of the things that we still don’t understand:
Science has yet to decipher this basic human action. Nobody knows why we do it, or why it’s associated with sleepiness. There are a few theories, however. One argues that yawning cools the brain and boosts its performance. When we are drowsy or overheated, a yawn acts like a fan, bringing the human machine back to a balanced temperature and functionality. Scientists claim that the answer might originate with the prehistoric animal instincts of the human species: contagious yawning as a way to maintain group vigilance and safety.
2. Spontaneous combustion
You didn’t know that there are 120 reported cases of humans spontaneously going up in flames? There are. The first recorded case dates as far back as the 17th century: an Italian knight burst into flames after drinking alcohol.
Most of the victims share one characteristic: they smoke. This leads scientists to believe that in the case of a spontaneous combustion, a cigarette or other outside flame actually burns the skin deeply enough to ignite fat that has leaked into clothing – much the same way a candle works.
A competing theory – that methane gas buildup inside a human body is sparked by mixing chemicals – is much less feasible, especially in light of tests on pig skin, which can combust in a very similar way.
3. Placebo effect
The power of placebos to produce actual results has been creating chaos and confusion for drug companies for ages. A placebo is a fake pill or injection which is given to test subjects so that scientists and doctors can weigh the added effects of a given actual medicine or therapy. Test subjects are not told that their pill is a fake, with absolutely no effect whatsoever. Many times, however, test subjects report effects resulting from the placebo. Additionally, sometimes tests show that the placebo has indeed had an effect in line with what the actual drug would have. How is this possible? Most explain the phenomenon by means of the power of the human psyche. There could be an actual physiological response, related to Pavlovian conditioning (a patient expects to feel better after medicating).
4. The first ancestor
All of the life on earth shares some common genetic attributes: proteins and nucleic acids, usually. The small core of genome sequences found by researchers across major branches of life’s family tree suggests that all living things came from one source, known as the “universal ancestor.” So what is this original organism? We don’t know. Scientists postulate that it lived approximately 2.9 billion years ago. In other words, it’s a little too late to know for sure. Don’t be fooled, we’re not talking about anything as complex as a tree or reptile – the universal common ancestor was some kind of one-celled organism.
Identifying the exact process or location of memory has eluded scientists until now. It’s been proven that memory is stored in various neurons in either the hippocampus or the neocortex areas of the brain. How the brain activates particular neurons in a sequence, however, is currently beyond science.
6. Cell count
Every organism on earth starts out as one cell that divides into trillions, according to a genetic code. The types and number of cells, as well as their placement and job, are all dictated by the cells themselves. So how do cells know when to stop growing?
Science has identified certain proteins which send signals back and forth between cells, regulating growth. However, where and how these intercellular signals originate is unknown. Once the trick is discovered, such knowledge could lead the way to finding a method to “turning off” diseased cells, such as those that constitute cancer.
7. Sex smell
Animals often communicate by excreting substances that give off a particular smell, signaling things like danger or desire. Do humans do so as well? The jury is out. While there are some studies that show the human body sending “chemosignals,” scientists know neither what those chemicals could be nor how a person could be detecting them.Don’t fall prey to product marketing that claims to have human pheromone-induced responses.
Gravity is the weakest of its sibling forces – electromagnetism, weak nuclear force, and strong nuclear force. Science doesn’t know what it’s made of, which particles comprise it, or how it works on a small scale. These unanswered questions keep science from relying on one universal theory (quantum theory or Einstein’s relativity) to explain everything that exists.
9. Species count
Science does not know how many species of things exist. Ever since ancient Greece and Egypt, taxonomists have been recording the earth’s species. Science is currently cataloguing 16,000 new species every year, and it’s nowhere near finished. The main problem is the enormity of the job – it would take 300,000 lifetimes to record all the species in the world. Secondly, biodiversity is spread out in some very hard-to-reach places, like the dark depths of the ocean – making research a tad difficult. Estimates of the total number range between five and 15 million species.