Friday, 26 February 2016

Sketchy Fact #113: The War on Mars

The world spends more on military expenses every 13 hours than it cost to send the Curiosity rover to Mars.

Wednesday, 24 February 2016

The World’s Deadliest Animal: Zika Virus and the End of Mosquitoes

Mosquitoes are the worst. Nothing ruins a hike or a camping trip like a swarm of these blood-sucking, ear-buzzing, itch-inducing pests. Most of the world’s population will, at some point, be confronted with these horrid little animals and ask the inevitable question: do they even serve a purpose?

At their worst, mosquitoes go from being ridiculously annoying to horrifyingly dangerous. We may have a more palpable innate fear or sharks, lions, and snakes but let’s not forget that the deadliest animal on the planet is tiny and airborne. Mosquitoes spread disease like it’s their job. Malaria, Dengue Fever, West Nile, mosquitoes carry them all. It is an incredibly fortunate genetic quirk that they can’t spread HIV. For some reason, the virus dies when subjected to a mosquito’s internal environment, but if the day ever comes when a mutation changes that, then we could all be in big, big trouble.

The latest world health crisis is the spread of the Zika virus in Central and South America, brought to you (as you might have guessed) by these two-winged demons of the sky. Zika isn’t especially horrifying in its obvious symptoms. Whereas Ebola victims violently lose bodily fluids until their organs shutdown, 80% of people with Zika never suffer so much as a sniffle. For the one-in-five people who do get sick, things aren’t all that bad either as far as public health crises go. Most commonly, Zika will give you a rash and a fever that subsides in a week or so. At worst, you might get some dry, itchy eyes as well, but Zika is no worse than an afternoon at your aunt’s cat-infested bungalow if you happen to have an allergy.

The real threat from Zika is to pregnant women, or more specifically, their children. Zika has been linked to devastating birth defects, most famously microcephaly. Microcephaly is a condition where babies are born with small heads and brains. It is often responsible for severe mental deficits, which is what makes Zika so scary. A pregnant woman can pass the disease onto her baby without ever knowing she has it.

Zika is spread almost entirely by mosquitoes in tropical countries. A few cases have been linked to sexual contact between people, but the usual process is that a Zika-infected mosquito bites a person who becomes infected, and that person is bitten by more mosquitos, who in turn become infected and spread the disease to everyone else they bite. That means that Zika can spread rapidly and is very difficult to control. Health experts predict that eventually every country in the Americas, except for Chile and Canada, may become infected.

Researchers are doing their best to develop a vaccine, but the most effective method to fight Zika might be to target the mosquitoes themselves. If we decided that it were ethically justifiable to do so, we could potentially bring mosquitoes to the brink of extinction, using what we already know about genetics. Even before the current Zika outbreak, scientists had raised the question of wiping them of the face of the Earth. The method is shockingly simple. Genetically modified male mosquitoes are released into the wild to breed with females. The females lay eggs as normal, which hatch into the next generation. The only catch is that all of the offspring are sterile.

It may sound like a small-scale solution, but researchers are confident it could work. It has been estimated that genetically-altered males could wipe out 80% of the world’s mosquitoes in 36 weeks. Within a year, the world could be basically mosquito-free. It would be a canoeist’s paradise.

The problem is one of ethics and unforeseen consequences. First, should humans be allowed to wipe out another species just because we don’t like them and we are able to do it? What makes our existence so much more valuable than theirs? It’s especially troubling when you consider that humans, not mosquitoes, are the cause of much of what currently ails the world, from climate change to pollution to species extinction. Second, what if we’re missing something? What if mosquitoes play a vital role in our ecosystem that we don't yet understand and removing them brings it crashing down?

It may seem far-fetched, but consider the fact that the only reason most of the remaining rainforests in the world haven’t yet been cut down is because of the threat of mosquitoes, according to science writer David Quammen. If we wipe them out, who is to say that another Las Vegas won’t pop up along the banks of the Amazon, destroying one of the richest environments on Earth? These are big questions that require thought, but it is hard not to see the merit when you consider the pain one little pest can cause.

Friday, 19 February 2016

Sketchy Fact #112: Spider Stats

Statistically speaking (not in reality), you are always within three feet of a spider. Though spiders are scarce in some places, their insane densities in others (like English pastures - 842 spiders per square meter) more than make up for it.

Wednesday, 17 February 2016

Ride the Gravitational Wave: Einstein Continues to be Proven Smart

Albert Einstein was a pretty remarkable guy. There aren’t many scientists of whom we have videos and recordings of speeches who command (and deserve) the same level of respect as people like Isaac Newton and Charles Darwin. To appreciate just how far ahead of his time Einstein was, consider the fact that his paper outlining the principles of General Relativity was published on November 25, 1915 – 100 years and 83 days ago as of this writing – and researchers announced the detection of one of his predictions last Wednesday. Most of us can’t even predict what we will have for lunch the day after tomorrow.

At a time when, outside his office window, he was just as likely to see a horse and buggy as a car, Einstein predicted the existence of gravitational waves. To understand how gravitational waves work, you first need to understand a little about the theory of relativity. If you want a detailed look at some of the weirder parts of this insanely cool model of the universe, check out our two-part discussion on relativity here and here.

For our purposes today, all you need to grasp is that Einstein claimed that gravity isn’t a force onto itself, but a side effect of dense matter in space-time. The classic analogy is to imagine a bowling ball on a mattress. The dent made in the mattress by the weight will pull any smaller object you set down towards the bowling ball, and that is gravity. A planet, sun, or black hole distorts the space around it just like the bowling ball distorts the mattress, pulling objects toward it. This idea ran counter to some of Newton’s ideas for complicated reasons you can learn about in this video series.

One of the predictions made by Einstein to support this theory was the existence of gravitational waves. Einstein suggested that if two very heavy objects were in motion around each other (imagine two scientists holding each other’s hands and spinning in a circle) they would send radiating waves of distortion out into space like ripples coming off a rock dropped into a pond; only, these waves move at the speed of light. This prediction was kind of a tease back in 1915, because it would have been all but impossible to measure.

See, the problem with space-time is that we all exist as a part of it. We are not sitting by the side of the pond with a ruler trying to measure the ripples; we are the water. When any instrument you use to try to measure something distorts in perfect unison with the thing you are trying to measure, you’ll never be able to detect anything. Fortunately, 21st century scientists have figured out a work-around of sorts.

To detect gravitational waves researcher built two facilities, one in New Hampshire and one in Louisiana, between which they could compare data. Each facility basically consists of two enormous pipes, each nearly 4 km (2.5 miles) long that are joined at a right angle.

At the joining point is a laser that is split into 2 beams and shot down both pipes simultaneously. At the end of each pipe is a mirror that reflects the laser back to the point of origin. If a gravitational wave were to pass through the pipes, one beam would appear longer that the other as the space it occupies expands; then a moment later, the beams would switch proportions as the space contracts.

That is exactly what happened on September 14, 2015. Both facilities, less than one ten thousandth of a light-second apart, observed a gravitational wave pass through them. The wave is thought to have been caused by two black holes that collided over a billion years ago in another galaxy - crazy, right? The great thing about gravitational waves is that they pass through everything they come into contact with without slowing down, so we can detect them from very far away. Basically the detection amounts to hearing the sound of black holes colliding.

This technology will be used to help us understand the makeup of the Universe and what things were like at the moment of the Big Bang. The scientific community is pretty confident that somebody is getting a Nobel Prize for this. The coolest thing about the discovery, though, is that the wave the researchers detected almost perfectly matched the numbers in Einstein’s prediction, meaning the sound of two black holes colliding sounds a lot like a German physicist easing back into his desk chair whispering, “nailed it.”

Wednesday, 10 February 2016

Alex St. Martin: The Man with a (literal) Window into Digestion

Generally speaking, the things science teaches us are the result of small experiments that push forward our understanding of the world, a little bit at a time. However, every once in a while, an event or a person comes along that gives our knowledge a rapid jolt forward. When these people are scientists, we tend to remember their names (Newton, Einstein, Darwin, etc.), but we tend to forget the names of the ordinary people who, often through extraordinary circumstances, taught us things about our world that we otherwise wouldn’t know. A few months ago we learned about Phineas Gage – the man who took an iron bar through the head and lived to tell the tale – and everything he revealed to science about the brain. Today, we’ll meet another similarly unfortunate individual.

On the 6th of June 1822 , at Fort Mackinac, a fur trading post in northern Michigan, an 18 year-old man named Alex St. Martin was loading up his canoe for another hard day in the woods. St. Martin was a French Canadian fur trapper, a tough breed to begin with; but before lunch time he would prove himself to be of heartier stock than the average voyageur. Sometime that morning, a gun accidentally went off. Word arrived with the Fort’s doctor, William Beaumont, that St. Martin had been shot. He rushed to the scene and inadvertently stumbled into one of the most fruitful partnerships in medical history.

St. Martin lay bleeding in the street with a hole in his rib-cage about the size of the palm of his hand. Through the hole spilled all manner of gore. There were bits of bone, muscle, and even part of a lung. But what caught Dr. Beaumont’s eye was the meat, bread, and coffee which, hours earlier, had been St. Martin’s breakfast. The bullet, it appeared, had punched a hole into the man’s stomach. Beaumont stitched up the wound, and over the next several weeks, performed a number of surgeries without the aid of anesthetic or disinfectant. St. Martin miraculously survived all this, but understandably grew fed up with surgeries. The end result was that he reached a stable condition but still had a hole in his stomach.

The medical term for the hole is a fistula. Today, farmers routinely give them to cows so they can monitor their digestion, but back in 1822 it was a new and valuable concept. In the early 19th century, the stomach was something of a mystery. We knew that food went in and waste came out, but we had basically no idea what went on in between to turn food into muscle and energy. The opportunity wasn’t wasted on Dr. Beaumont who, under the guise of charitable action, offered St. Martin a job as a handyman at his home to make up for the fact that he could no longer trap. With few options, St. Martin agreed to take the job.

Things presumably started out normally enough, but eventually Beaumont somehow convinced St. Martin to allow for a few experiments. In 1825, Beaumont began lowering bits of food through the fistula and into St. Martin’s stomach on pieces of string. He would pull the items out after various amounts of time and record how digested they were. This is how science learned that hard-boiled eggs take three and half hours to digest and boiled animal brains take an hour and 45 minutes. Beaumont also took to tasting the stomach juices and the fistula itself to measure acidity… In short, things got weird.

In fact, they got so weird, that eventually St. Martin had enough and fled back to Canada where he started a family and even began trapping again. Beaumont didn’t give up; he wrote letters, pleading with St. Martin to come back, offering him money and land to support his family. Apparently having a hole in your stomach is a significant disadvantage in the fur trapping game, because St. Martin did agree to go back after several years.

It was during this second stint as Beaumont’s live-in guinea pig, that the fistula experiments really began to advance science. Beaumont eventually discovered that when food was introduced to the stomach, papillae emerged from the stomach wall and secreted a clear fluid that was the means of digestion. This was the first evidence that digestion is a chemical, and not a mechanical, process. Beaumont eventually proved this idea by removing some stomach acid and observing digestion outside the body.

This work made Beaumont famous. He toured the world demonstrating his findings, often with St. Martin in toe as a medical side-show of sorts.

St. Martin lived out the rest of his life (he lived to be either 78 or 84 depending on who you ask - either way, a long life) as an oddity. Upon his death in 1880, his family opted to delay burial so his body could begin to rot, eliminating the chance that doctors would dig him up for an autopsy. If we can take one additional thing away from St. Martin’s life story, it is that scientific leaps sometimes come at a cost. Modern medicine owes a pretty big debt to tough and tolerant patients like him.

Wednesday, 3 February 2016

Head Transplants: Get 6-Pack Abs the Hardest Way Possible

Your head is a very personal thing. It is what people use to identify you. It is the exclusive home of four of our five commonly recognized senses. It is the case that contains our brains, the source of everything we know, think and feel. Even our language recognizes the importance of the head in personality and intelligence. Someone acting crazy is said to have “lost their head” and a company’s primary office is their “head”quarters. There is one surgeon currently working in China, however, who might force us to raise some questions about where our heads fit into our identities.

Earlier this year, Dr. Sergio Canavero duplicated an experiment first attempted in the 1970’s. He cut the heads off of two rhesus monkeys, tossed one in the medical waste bin and sewed the other onto a body to which it didn’t belong. By lowering the temperature of the head to 15°C (59°F) and carefully maintaining the blood supply, Dr. Canavero demonstrated that the monkey could survive the operation without sustaining brain damage. His goal is to carry out the procedure on a Russian (human) volunteer, who suffers from a fatal, muscle-wasting condition called Werdnig-Hoffman disease.

The story isn’t all head-swapping good times, however. The monkey that survived the procedure may have found itself envying the one whose head ended up in the waste bin because, while it may be technically possible to maintain blood flow and avoid brain damage, there is one significant obstacle to performing totally successful head transplants: reconnecting the spinal cord. In the end, the monkey was euthanized a few days after the operation due to ethical concerns. Those concerns included the subject not being able to walk, breath, make noises, or control its bladder. The actions the transplanted head was capable of were limited to moving its eyes and facial muscles and attempting to bite whoever came near it… not that you could blame him.

What it comes down to is that your spinal cord is a remarkably complicated thing. The twisting rope of nerves, that winds its way down your backbone and into every part of your body, is what allows the lump of grey matter up in your skull to interact with the world. To make an out-of-date gaming reference, it is the equivalent of the cable connecting your Nintendo 64 controller to the game console. Sever it, and Mario becomes pretty immobile pretty fast. And the real kicker is that over the thousands of years we’ve been making progress in medicine, we still haven’t figured out a way to fix a disconnected spinal cord.

The problem is that, unlike most parts of your body, your spinal cord doesn’t regenerate on its own. We know that after an injury, nerves begin to reach out to reconnect with other parts of the body but chemicals released at the point of injury and scar tissue prevent the recovery from having any real effect.

Things aren’t all doom and gloom, however. Some research in the past decade has begun to inch closer to a treatment for spinal cord damage, making head transplants a slightly less crazy notion. In 2013, researchers at the Case Western Reserve University and the Cleveland Clinic showed that when they severed the spinal cords of 15 rats, they were able to regain some basic functions, like bladder control, by bathing the nerves in a mix of two chemicals, Chondroitinase and Fibroblast Growth Factor (FGF), and reinforcing the connection with some metal wiring.

Even more impressive, in 2014, surgeons in Poland, lead by Prof Geoff Raisman, chair of neural regeneration at University College London's Institute of Neurology, treated a paralyzed man’s spinal cord using cells from his own body and observed that, with physical therapy, he was eventually able to regain the ability to walk with the help of a metal frame. The treatment took cells from one of the man’s olfactory bulbs – normally used to smell stuff – and transplanted them into his spinal cord above and below the site of the injury. The gap between the two sections of the cord was reconnected using nerve tissue from the man’s ankle. Researchers believe that because the olfactory bulbs are one of very few areas where neurons regrow throughout a person’s lifetime, they may be the key to treating paralysis without fear of the body rejecting the new tissue.

Even with these breakthroughs though, the head-switching Dr. Canavero deserves some criticism. Aside from the ethical issues that go along with torturing monkeys, he breached scientific protocol and reported his findings to the media before any other scientist had a chance to review them, making his claims doubtful at best. In the end, it may be a while before we can put our heads onto younger, fitter bodies but with properly conducted research and a steady supply of funding, we may be able to help paralyzed people walk again. That is the work that is worthy of our attention.