The scientific method is all about getting to the bottom of questions large and small. It will be an invaluable tool for as long as there are questions to be answered. That’ll be until such time as science gives us a quantum computer that can compute the Universe. And then, said computer will still be an end result of the scientific method.
That said, it can sometimes work very… very… slowly. From the mundane to the fantastic to the extraterrestrial, here are 10 questions scientists banged their heads against for a very long time until the answers came.
10. What Causes Volcanic Lightning
A long-observed quality of violent volcanic eruptions are the crackling electrical displays associated with their ash plumes. While awesome to look at (from a safe distance), the phenomenon has long puzzled scientists in that it is obviously a separate one from regular, earth-bound lightning, and had no apparent cause.
The answer, according to University of Munich researchers, lies within the ash itself. Specifically, tiny particles of rising ash that are electrified by magma. Particularly in the violent lower regions of the ash plume, where the turbulence generates complex charge distributions, this eventually leads to an electrostatic discharge. One which often propagates upwards, instead of downwards like regular lightning, due to the rising ash.
The answer to this question isn’t just useful for satisfying curiosity. The study also unexpectedly showed a correlation between the frequency of the lightning and the total volume of ash that the eruption will generate. Observing the phenomenon could therefore lead to accurate predictions about the sizes of each ash cloud. That, in turn, could result in better evacuation planning and air quality alerts.
9. Why Turtles Have Shells
The question of what caused turtles to evolve their shells would seem to have a simple answer. Turtles are notoriously slow, making them easy pickings for predators. A hard protective shell is an obvious evolutionary advantage. But examination of the turtle’s evolutionary process shows this to be false. Turtles are slow because of their wide, flat ribs, a feature distinct from almost all other animals, and which is necessary to support their shells. That is, turtles are slow because they have shells. So why have them at all?
Well, for protection, yes. But not from predators; from the harsh South African desert environment in which turtles evolved. Specifically, the turtle’s shell began as a means of digging underground, creating caves to escape the heat and aridity.
Though long suspected, final confirmation of this theory did not arrive until an 8-year old South African boy stumbled upon a well-preserved, only partially shelled “proto-turtle” fossil while working the family farm. Fortunately, the family took the specimen to a local museum and enabled researchers to put this burning, slowly ambulating question to rest.
8. Why Jet Lag is Directional
Frequent fliers know that when traveling from West to East, the effects of jet lag are much more pronounced than when traveling from East to West. This was long suspected to be all in the head of the traveler, or perhaps due to public consensus that this is just how jet lag works. But it was recently found that the effect is real, and there is a reason for it. It has to do with your Circadian rhythm, and its role in how long it takes your brain to “sync up” after a time zone shift.
Simply put, the body’s natural clock is generally set to be slightly longer than 24 hours, and it varies for each individual. This being the case, the body is naturally geared toward adjusting to longer days rather than shorter. Certain cells in the brain control this rhythm, but these cells are themselves controlled by variations in sunlight.
When days are lengthened and sunlight is prolonged, there is still a “signal” (sunlight) feeding information to these cells. But they become confused in the absence of sunlight, or when days are shortened. This throws off the body’s internal clock. Since traveling from West to East has the effect of shortening the day, our internal rhythm is thrown more severely out of whack in this scenario – our natural inclination toward longer days being a contributing factor.
7. Why Knuckles Pop
You may have heard that the popping sound when cracking your knuckles is the result of bubbles in the joint fluid, which collapse when the joint is moved a certain way. You may have even taken this as fact for a very long while. But it turns out that this whole time, that was pure speculation. In an experiment that we honestly can’t believe it took somebody so long to perform, University of Alberta Canada researcher Greg Kawchuk got somebody who is really, really adept at cracking his knuckles, stuck his hand in an MRI machine, and got to the bottom of the whole thing.
Rather, the subject came to him. Jerome Fryer is a “champion knuckle cracker” who also happens to be a chiropractor. He came to Kawchuk with his theory: the sound results from the sudden formation of a cavity inside the joint fluid. Not its collapse, but the actual formation of the cavity: “It’s a little bit like forming a vacuum… as the joint surfaces suddenly separate, there is no more fluid available to fill the increasing joint volume, so a cavity is created, and that event is what’s associated with the sound.”
You may have also heard that cracking your knuckles causes arthritis, which is almost certainly untrue. However, this new study could disprove that notion once and for all. It could also lead to better early treatment and diagnosing of joint problems.
6. The Function of the Appendix
For centuries, the appendix has been thought a vestigial organ. An evolutionary leftover, with no purpose other than occasionally to serve as a ticking time bomb which will kill us if not removed immediately. While it’s true that we can function perfectly normally without one, research has uncovered the hidden purpose of the appendix. It’s a sort of reserve barracks for the additional platoons of good bacteria needed to fight particularly nasty infections.
The discovery was made by examining the appendices of koala bears, which have comparatively long and large ones. They’re needed to aid in the processing of their diets, which consist of practically nothing but Eucalyptus leaves. It’s speculated that if koala’s diets were to change, over thousands of years, their appendices would shrink as ours have.
Duke University Medical Center professor Bill Parker, who participated in the research, stressed that this by no means implies that we should now try to hang on to our appendix at any cost. “It’s very important for people to understand that if their appendix gets inflamed, just because it has a function it does not mean they should try to keep it in,” he says.
5. Whether Memories Can Be Inherited
Epigenetics is the study of how genes can be altered by environment, writing changes into our DNA which can then be passed on. For example, it has been shown that things like dietary habits or exposure to environmental toxins can result in having offspring which inherit certain food or chemical sensitivities. What was not known until recently was whether experiences can have the same effect. For instance, if a traumatic childhood on the part of a parent can result in changes to a child’s DNA.
A Tel Aviv University research team recently not only confirmed that this is the case, but revealed the exact mechanism that serves as an on/off switch for inherited environmental influences. It was previously known that small RNA molecules are somehow key in facilitating inherited DNA modifications. In measuring epigenetic responses in worms, researchers were able to isolate an enzyme that essentially tells the small RNA molecules to keep replicating. This determines over how many generations the epigenetic response persists.
It was further discovered that by manipulating this “switch” that epigenetic responses – like passing down a fear response learned by a prior generation – could be prolonged or terminated at the researchers’ will. The implication, of course, is that a similar switch in humans could be manipulated to proactively help those predisposed not only to physical conditions, but emotional and mental conditions as well.
4. Why Subatomic Particles Bind
In particle physics, the quark is the tiniest, most elementary of all particles. If quarks are composed of anything smaller, we don’t know about it yet. They in turn make up protons and neutrons, which are bound together by… force. Up until recently, nobody was sure exactly what that force was. But we now have a pretty good idea. It’s yet another kind of particle.
Scientifically known as meson f0(1710) but referred to as the gluon (yes, really), the particle acts as the glue which binds all other particles together. They are similar to photons (particles of light) in that they have no mass of their own. Yet, similar to how photons are responsible for electromagnetic force, gluons are responsible for strong nuclear force. The key difference: photons aren’t subject to their own force, while gluons are. Meaning that they’re able to bind together.
Existing for too short a period of time to be examined directly, gluons were discovered and can be examined by their detected rate of decay. More specifically, groups of bound gluons – called “glueballs”- are basically what’s holding the entire Universe together.
3. The Nature of Gravity
Albert Einstein’s Theories of Special and General Relativity have held up better than perhaps any other incredibly significant scientific theories. Their applications have led to the development of semiconductors, to name just one thing. Without those, you wouldn’t be reading this. But even the soundest theories, backed by reams of research and decades of practical applications, can have their holes. For relativity, that hole was gravity.
Einstein’s theories assumed that, like light, sound, and practically everything else, gravity is expressed as a wave or frequency. This was, in fact, the last major prediction of relativity to be fulfilled. This has generally been held to be true for decades, but wasn’t confirmed until recently, and in rather spectacular fashion.
Using extremely sensitive instruments, scientists recorded the distant sound of two black holes colliding. The faint, rising tone represented the energy of the collision – 50 times the power output of all stars in the Universe combined – conveyed by gravitational waves to the measuring device. This tone may soon become a hallowed recording in the annals of science, as it all but completes Einstein’s vision. Using this new discovery, astronomers will be able to construct instruments that can “hear” deeper into space than ever before. That black hole collision that was measured? It was two billion light years away.
2. Why There Are Men
Humans have evolved to become very efficient organisms. However, our method of reproduction does not seem to suit us in that regard, strictly speaking. While we may find it enjoyable, sexual reproduction pales in comparison to asexual reproduction, exhibited by many animal species, in terms of efficiency. If humans have followed their most advantageous evolutionary course, there should be only one human sex (female) which would reproduce all on its own. So, why are there men?
Researchers may have found the answer in a study involving flour beetles. The study had two parts. In one, 90 males and 10 females were put together and observed. In the other, just one male and one female were paired up. After 50 generations (!), it was found that sexual selection seemed to play a significant role in producing healthy offspring.
This is likely because having a choice of mate can act as a means to filter out harmful genetic mutations. That’s according to lead researcher Matt Gage of the University of East Anglia. This suggests that not only would asexual reproduction not have been more efficient for us, but that if we did not reproduce sexually we probably would have gone extinct.
1. Whether There Have Ever Been Aliens
Answering the question of whether we’re alone in the Universe is one of the holy grails of science. Almost as compelling is the question of whether extraterrestrial life has ever existed. We have no frame of reference as to how long a civilization might potentially last. Or, where on the cosmic timeline one might have existed. And we haven’t found any physical evidence. However, extremely strong circumstantial evidence has recently become available which all but answers the question definitively.
And, the answer is yes. In 1961, astronomer Frank Drake identified seven factors (expressed in the form of an equation) which identify the odds of contact with an alien civilization. They include the number of stars born each year, percentage of planets upon which life evolves, and so on, with the final factor being the average lifetime of a civilization. Most of these factors being unknown variables, there was no way to effectively use the equation to arrive at any kind of solution.
However, in the intervening years, knowledge of the number of planets has increased exponentially. That’s allowed figures to be plugged into Drake’s equation and shed some light on the issue. In a recent paper, astronomers Adam Frank and Woodruff Sullivan ran the numbers to arrive at a startling conclusion: “unless the probability for evolving a civilization on a habitable-zone planet is less than one in ten billion trillion, then we are not the first.” Frank also stated, in a New York Times op-ed, “In previous discussions of the Drake equation, a probability for civilizations to form of one in 10 billion per planet was considered highly pessimistic. According to our finding, even if you grant that level of pessimism, a trillion civilizations still would have appeared over the course of cosmic history.”