2013 Review Part 2


In the previous article we saw how scientists from all around the world had managed to print a gun, create a fake burger and allow a human and a rat to communicate only using their minds! We also saw how two excelling scientists were honoured with the most prestigious scientific award, the Nobel Prize, for their theory of how particles gain their mass. Last but not least, we reviewed the meteor that hit Russia and fascinated observers and astronomers alike.

But 2013 was a very busy year, and there are still things that have to be remembered. For example:

6. Life Can Be So Hard

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Lake Vostok in Antarctica

Humanity has not yet found a planet with living organisms in it, because conditions can be very harsh and inhospitable, unlike in our planet. Or maybe not.  I’m talking about Lake Vostok, in Antartica, where this body of water rests under 500 metres of ice, under extreme temperatures and pressure, and where no sunlight can reach. Immediately, you’d think there can be no life here, but a team of Russian scientists proved last year that there may be, when they drilled through all the ice and extracted a sample of water that contained pieces of DNA.

If life is definitely found, it will most probably be single-celled organisms, not macro-organisms such as fish or sharks, although if there’s anything we’ve learned from this adventure is that life can be found in the most unprecedented places, not matter what form it takes.

7. The Memory of the Smell of Fear

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Memories travel generations in rats

A study carried out last year showed that memories can be transmitted from one generation to the next, and not by talking about it. The case was that a group of rats were subjected to the smell of cherry blossom, and after this, gave them an electric shock, so every time they smelled this, they would become wary and tense. Then, these rats were reproduced, and, surprisingly, the children also became alert when detecting the smell.

Although the mechanism is not yet understood, it may have something to do with changes in the DNA (like switching on and off certain genes) due to chemicals being released in your body.

This phenomenon can happen with other events, not just smell, but others are more difficult to track, since there are a lot of genes involved. Smell, specifically cherry blossom, is easier because there are specific receptors that react to this smell, which scientists already know about, so changes in these can be seen easily enough. Also, its not only the fact that the offspring must remember the smell, but also the feeling that comes with it, fear.

8. The Oldest DNA

In a cave 30 metres below ground, a paradise for archaeologists lies. There, the oldest genome ever discovered has been processed, yielding incredible results.

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Denisovian Hominid

This fantastic place is the Atapuerca cave, found in Spain (my home country), and has always been considered a gold mine for anthropologists. It continues to meet its expectatives, as in a shaft, they found the remains of 28 hominids, of which a thigh bone was extracted. Although extracting a good sample of DNA from such an old sample, especially in a warm climate, is very improbable, scientists tried anyway, and thank God they did. The genome found is 400,000 years old, twice the age of our current species. The surprising thing about his genome is not only its antiquity, but also that it shows the bones found in the shaft known as ‘the pit of bones’ is not Neanderthal, but of a different species of humans called Denisovan, of which very little is known. But with this discovery, maybe we will find out all we need to know about them, and complete the puzzle of our many ancestors.

9. The Most Crowded Trench 

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Mariana’s Trench, the deepest point on Earth

Director James Cameron, known for movies such as Titanic, Avatar or The Terminator, will be remembered by the scientific community for more than his movies.

Last March, he organised the Challenger Deep expedition, which travelled 11000 metres underwater to the lowest point of Earth, the Mariana’s Trench. He stayed there for about an hour, collecting samples and recording everything he saw.

Although the area was not teeming with macro-organisms, unfortunately for Cameron, samples from the submarine show there were unusually high levels of bacteria in the water. For every cubic centimetre, there were 10 million bacteria, a surprise for scientists because the amount of organisms down there was higher than in shallower areas, where conditions are less hostile. A possible explanation is that trenches are extremely good at collecting ‘food’ (organic matter from creatures above), so bacteria would have enough material to survive, even though the pressure and temperatures are not too comfortable.

 10. Blob of Pitch Falls

Pitch, a substance that makes up petroleum, is also one of the most viscous substance known to man, and its qualities can be quite interesting.

Decades back, someone in Trinity College Dublin set up an experiment that consisted in adding a measure of heated pitch to a glass funnel, and then let gravity do its job. The original version of this experiment, however, was done in University of Queensland, Australia, by Thomas Parnell, whose objective was to show and measure how viscous this liquid really was, though he died before it could actually happen.

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The Pitch Experiment

But it was in Dublin where the magic really happened. After years of the pitch standing abandoned in an old shelf, scientist Shane Bergin found it, and after figuring out what it was, set up a web cam and connected it to the Internet so everyone was able to observe the liquid, in case a drop fell. And that is precisely what happened, the 11th of July, after years and years of patience. Although the real purpose has been completed, the web cam is still connected, and it is expected that in the next decade, another drop falls, so be attentive.

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Life is all about Change


In an experiment in Michigan State University, scientist Richard Lenski started growing a group of E. coli bacteria in 1988. The bacteria have kept reproducing since then, making the incredible amount of more than 50,000 generations. But there is a purpose to this experiment: study evolution and answer a very simple question: Is there an end to evolution?

Lenski grew about 12 different groups of E.coli bacteria in a simple, constant medium. He used bacteria because this type of organism grows and reproduces very quickly and they are fairly easy to manipulate and study. It was important that the environment was kept constant, because any little change could affect the evolutionary process.

After every 500 generations, a sample was taken and frozen, so at some point, a group of bacteria from different generations was put together and their aptitude at surviving compared to each other is be measured.

The results are very surprising and revealing. Every generation, Lenski found, had a minor improvement over the former one. The grandson was always fitter than the grandfather; no matter how many times the experiment was repeated. But this was expected. The news is that, at some point, the improvements were less and less obvious, so even though there were still changes, they weren’t so useful or noticeable with each generation.

E. Coli bacteria

E. Coli bacteria

This is an example of power law, a mathematical term used to describe a sequence that is ever increasing, but the amount by which it grows, decreases.

This information is interesting because, up until now, it was thought that organisms had a limit as to how adapted they could be. This applies only to constant mediums. In the real world, there is always going to be changes, because the environment or the habitat changes all the time, however small the changes are. So the answer to our first question was no. There are always changes around us, so we are always going to be changing. Even if the world stopped changing in every minute detail, we would still be developing new ways in which to be fitter for survival.

Some people say that this could not be applied to humans or other species, but the idea is the same. Just like your parents said, there is always something you can do to be better.

Homo erectus, The Pyromaniacs


This Tuesday, a group of international archaeologists discovered the traces of what looks like the oldest controlled fire made by humans. The remains and some microscopic residues of ash and burnt bones were found in the South African cave of Wonderwerk.

It is proved the fire was controlled and probably caused by the Homo erectus, the most possible candidate as the times match, as the fireplace was found 30 metres inside the cave, which practically discards the fact the fire was caused by wildfires.

However, the traces given are not conclusive when saying the hominids at that time ‘started’ the fire themselves. As Michael Chazan, from University of Toronto in Canada, says, it is also possible that the Homo erectus carried the fire from outside the cave and brought inside, which rules out the theory that says that they made the fire.

This discovery is not only important because it is the oldest proved hearth in history, having 1 million years, but because it will also be very useful for anthropologists to show how at this time, hominids developed a taste for food. This finding will reactivate the debate that cooking changed forever the human anatomy.

As Richard Wrangham says, at Harvard University, this finding is an exciting breakthrough, which makes many scientists think that other areas from South Africa with 1 million years old should be re-examinated.

Wrangham gives lots of importance to this discovery as it could be a conclusive prove that around that time humans started cooking food.

Despite this, Chazan also argues that the tiny trace of fire really contrast the great amount of ashes found in other fires of more recent sites. This, says Chazan, indicates that the Homo Erectus didn’t use the fire frequently or cooked regularly.

Wonderwerk Cave

This is not the first finding of extremely old hearths. The oldest hearth found (before the South African was discovered) was found a few years ago, the residues of ashes, stones and bones were found in an Israeli land, and dated from only 790,000 years ago.

However, many scientists state that humans were able to cook and control fire much earlier, since 1.9 million years ago, although there are no scientific proves.

It is clear that this mystery will be difficult to solve, but, as Wrangham says, the problem is so fascinating.