When you look at the undersides of your hands and feet, do you ever wonder why there is no hair growing on them? Or maybe why certain areas of your body are smooth as a baby's bottom and how you wish they weren't? Well, the answer to that is the inhibitor Dickkopf 2 or DKK2.

In a paper published in the journal Cell Reports, researchers from the University of Pennsylvania in the US say they've found a naturally-occurring inhibitor secreted in developing hairless skin that blocks what geneticists call the Wnt pathway, which controls hair growth.

So perhaps the next thing we should try to find out would be whether the inhibitor can be deactivated or removed such that hair can grow in such areas.

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Despite being the epitome of human achievement, climbing Mount Everest is actually considered less difficult than climbing other mountains like K2 or even smaller ones but that may be due to the popularity of Everest and how it has become more commercialized throughout the years. It is still quite a difficult feat to do though if an individual or a group were to do it themselves without any expert help.

This story almost feels like an Agatha Christie novel except you don't really get closure from solving the case because until now, the case hasn't been solved.

Roughly a year ago, Tim Watkins was reported to have been missing and after three days, was found dead on a trail near where his bike was found. His body was buried underneath some logs. He had three shots on his body, the fatal wound being on his chest.

Nobody knows exactly why Tim Watkins was shot. But there have been a few more incidents that happened at Limbaugh Canyon. Still, the mystery lingers.

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Whenever the tectonic plates move in the Earth's crust, we feel it, most of the time. Some are weak movements that we generally won't notice while other stronger movements have evident manifestations like shaking the ground and even buildings and other structures.

But strange earthquake passed by without anyone knowing. Except one.

Only one person noticed the odd signal on the U.S. Geological Survey's real-time seismogram displays. An earthquake enthusiast who uses the handle @matarikipax saw the curious zigzags and posted images of them to Twitter.

These waves started off the shores of Mayotte. And then it spread around the world.

However, there was no big earthquake kicking off the recent slow waves. Adding to the weirdness, Mayotte's mystery waves are what scientists call monochromatic. Most earthquakes send out waves with a slew of different frequencies, but Mayotte's signal was a clean zigzag dominated by one type of wave that took a steady 17 seconds to repeat.

So what caused these strange waves? Read Maya Wei-Haas' article on National Geographic.

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Tiny as they are, it may be why most of us wouldn't possibly even consider insects having distinct auditory structures, let alone being able to use them in a way similar to how we hear.

One might think insects are simply able to sense their surroundings through vibrations and other external stimuli, processing them and responding to them. However, this article on Knowable shows us the weird world of insect hearing and how they are able to process sounds.

There are some obvious surprises about these insect ears, one being their location:

Location is the most obvious difference between one insect’s ears and another’s: There are ears on antennae (mosquitoes and fruit flies), forelegs (crickets and katydids), wings (lacewings), abdomen (cicadas, grasshoppers and locusts) and on what passes for a “neck” (parasitic flies). Among moths and butterflies, ears crop up practically anywhere, even on mouthparts. The bladder grasshopper has an abundance of ears with six pairs along the sides of its abdomen. Praying mantises have a single, “cyclopean” ear in the middle of their chest.

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When people are in a panic, especially in an emergency situation, the first thing usually that comes to one's mind is to get out and find a safe place.

But in the midst of a crowd, the probability of injury or serious accidents increases and so researchers have tried to develop a complete science of crowds using a range of disciplines.

One relevant concept from complexity theory is ‘emergence’, which occurs when the interactions among the entities produce group behaviour that could not have been predicted from the properties of any individual element. For instance, randomly moving H2O molecules in liquid water suddenly link up at zero degrees Celsius to make solid ice; starlings in flight quickly form themselves into an ordered flock.

With this research, we can help avoid casualties when panic is stirred by a terrorist attack, for example, when a large group of people gripped by fear would be stampeding and running for their lives. It is going to be useful for public safety and crowd control.

Sidney Perkowitz, a professor emeritus of physics, elaborates more on the topic at Aeon.

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Manuel Eisner from the Institute of Criminology at the University of Cambridge has recently developed an interactive map that details the different homicides that occurred in the bustling areas of medieval London.

It kicked off at a urinal in Cheapside, and ended in a bloody and brutal murder. Poor aim has been responsible for many unexpected deaths, but perhaps none more so than that of Philip of Ashendon.

One of a brutal range of fatal scuffles, revenge killings and infanticides recorded by London coroners in the early 1300s, Philip’s demise is among those to feature in a new interactive map that uses death to breathe life into medieval London.

Check out the map on the Violence Research Center page at the University of Cambridge site. Read more of Nicola Davis' article on The Guardian.

(Image credit: Manuel Eisner/University of Cambridge)

Do you like numbers and patterns? Would you like to take up the challenge and try to figure out some of these puzzles? All of these sequence puzzles featured on the video by the Numberphile were presented by Neil Sloane, a mathematician with contributions to combinatorics, error-correcting codes, and sphere packing.

When I saw this, I immediately think about Game of Thrones and the array of heads on pikes lined up outside the wall of the Red Keep. Or perhaps something similar to the moat of heads built around the Red Queen's castle.

Maybe these were inspired by how Formica archboldi also makes a display of their enemies' heads in their nests. But why do they do this? Adrian Smith, a research biologist, who has been studying such behavior has a few speculative hypotheses.

Whatever the reasons may be, one thing is for certain. As Corrie Moreau states, "This just shows that the more you know about nature, the more questions you uncover."

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We are told to listen to our parents and to some extent, I believe in that but I have also thought about such situations as that which Kenneth Kimes Jr. had been trapped in for most of his life. It must be a cruel twist of fate for a child, not being able to choose one's own parents, to have to grow up in such an environment of agony and confusion. But for Kenny, that's all he knew from childhood to adulthood.

This is his story. Of how his mother taught him how to kill. And how he found his morality behind bars.

(Image credit: Kenneth Kimes)

There are many small indigenous communities around the world whose languages are slowly becoming extinct. As societies become propelled toward modern civilization, these groups are being left behind and with the dwindling number of speakers of indigenous languages, it won't be long before they die out.

But in a small island off the coast of Australia, a certain linguistic phenomenon has been happening all this time.

On South Goulburn Island, a small, forested isle off Australia’s northern coast, a settlement called Warruwi Community consists of some 500 people who speak among themselves around nine different languages. This is one of the last places in Australia—and probably the world—where so many indigenous languages exist together. There’s the Mawng language, but also one called Bininj Kunwok and another called Yolngu-Matha, and Burarra, Ndjébbana and Na-kara, Kunbarlang, Iwaidja, Torres Strait Creole, and English.

One might think that the people living in this community must be capable of speaking several of these languages but in reality they don't. However, they are able to understand each other regardless. Michael Erard tells us more about the Warruwi Community.

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Before we had digital and atomic clocks, the world used pocket watches. But back then, these were expensive and often imprecise, such that no two watches could be relied upon to tell time.

In the height of the Industrial era, one man set out to manufacture a watch that would make timekeeping accurate and more affordable.

That man was Aaron Lufkin Dennison who observed how precision engineering was used in armaments manufacture and wanted to apply that to watchmaking. And so the Waltham Watch Company was born.

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This debate is really quite a toss up. There haven't been any conclusive evidence to say whether Neanderthals were able to speak the way Homo sapiens could but since there were studies that showed they interbred, maybe it was possible that they communicated with each other albeit not in the way we expect.

Discover Magazine's Bridget Alex writes:

Part of the reason scientists disagree about Neanderthal language is because there are different definitions of language itself. Without straying too far into academic debates over the nature of language, let’s just say there are broad and narrow theories when it comes to what actually constitutes language.

Speech and language are mostly soft-tissue operations, requiring organs like the tongue, diaphragm and brain that rarely preserve. However, producing and hearing speech influences some enduring aspects of our skeletons too, including the hyoid bone, ear ossicles and the portion of the spinal canal that holds nerves involved in precisely controlling breathing. Studies have found these features are very similar between Neanderthals and Homo sapiens, but more primitive and ape-like in earlier hominins like Australopiths.

The question of Neanderthal language remains an open debate. If they lacked it, language may be unique to Homo sapiens. If they had it, language was likely present at least since Neanderthals and modern humans shared a common ancestor, over 500,000 years ago.

So which team are you on?

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Capital punishment was pretty common in history and there have been some really gruesome and terrifying methods of carrying it out. The Halifax Gibbet was one such device that meted out justice through decapitation.

You may identify this device as a guillotine, famously used against members of the monarchy during the French Revolution, but the Halifax Gibbet predates the French guillotine by more than five centuries.

While decapitation was a fairly common method of execution in England, it was mostly carried out by swords. Halifax is believed to be the first place where a machine was used to carry out the punishment.

It was not until Oliver Cromwell that this barbaric practice was outlawed. Today, a replica of the Gibbet stands at Halifax and a commemorative plaque nearby lists the names of people known to have been executed by the device.

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The Civil War Photo Sleuth is on a mission to identify all the people whose pictures were taken during the Civil War era. They have developed a new facial recognition software that enables them to match the face to the name through 27 different facial landmarks.

CWPS has already identified more than 75 photographs and has hundreds more catalogued for eventual identification. The process of identifying unknown figures in Civil War-era photographs requires amateur detectives to draw on an arsenal of tools and skills: As Luther writes in a separate Military Images piece, researchers often augment print resources with a growing body of online data, including genealogical charts, military records and photographic archives, as well as tips offered by burgeoning communities of sleuthing enthusiasts.

To learn more about the project, visit the Civil War Photo Sleuth site. Check out more of the article by Meilan Solly at the Smithsonian Mag.

(Image credit: Betaface.com/Civil War Photo Sleuth)