Friday, 29 May 2015

Sketchy Fact #93: Beetles Rule the World

The Earth is home to 260 species of monkey and over 350,000 species of beetle. As JBS Haldane once said, “If The Creator exists, he has an inordinate fondness for beetles.”

Tuesday, 26 May 2015

Opah! Warm blooded fish derails conventional science

The study of biology can turn even the most open-minded person into a bit of a snob. As you learn about the infinite complexity of the living world and begin to understand how body systems have evolved to cope with a never-ending struggle for survival it is easy to fall into the trap of thinking one way of doing things is better than another. This can lead to thinking of some species as “primitive” compared to humans and over the course of history this idea has been used to justify some pretty heartless treatment of animals from testing cosmetics to making bears ride unicycles.

A great example of how biology tends to split up animals is the study of thermoregulation, or how animals control their body heat. Although there are animals that exists across a spectrum of temperature controlling abilities we tend to lump all the life on our planet into one of two buckets: warm blooded or cold blooded. Cold blooded animals (also called ectotherms) use forces outside their body (mainly the sun) to regulate their metabolisms. If they need to speed things up, they go lay in the sun for a while. When they begin to overheat, they go lay in the shade. Warm blooded animals, by contrast, can use internal forces like muscle contraction and widening or narrowing blood vessels to keep things in check, regardless of whether or not the sun is shining.

Generally speaking, the warm blooded camp includes mammals and birds  and team cold-blood includes everything else. The upshot is that since humans are warm blooded mammals and we are the ones who publish the bulk of the scientific papers on this planet, cold bloodedness tends to get spun as being “less advanced.” Fortunately, science builds its understanding of things over time and recent research is beginning to demonstrate that things aren’t quite as neat and tidy as some of us wish they were.

Fish, for example, are the quintessential primitive, cold blooded animals. When they leave the warm and sunny waters near the surface for a deep dive, they become sluggish as their bodies cool down… But not all fish. On May 15, 2015 researchers reported in the journal Science that a fish called the opah seems to defy this description.

The opah is a cool animal to begin with. It is roughly circular in shape, with powerful looking fins. It is red with white polka dots, and can grow to 90 kg (200 lbs) in weight and be about the size of a car tire. But it turns out that the coolest thing about the opah is that it isn’t really cool at all. The opah is the first fully warm blooded fish ever discovered. Through flapping its fins and changing the way warm and cool blood exchange heat in its gills, the opah can keep its body temperature 4 to 5 degrees C (7 to 9 F) above the temperature of the surrounding water. This gives it an advantage in hunting cold blooded fish at depth and means it never has to move to the surface to warm up.

Other fish like tuna and some sharks have been found to be able to heat up specific parts of their bodies when gearing up to hunt, but to avoid damaging their organs they eventually need to move to warm water.

The process used by the opah is actually pretty similar to how humans stay warm when its cold outside. When our body gets cold it sends a message to the hypothalamus in our brains, which acts as our internal thermostat. The brain constricts blood vessels near the skin and in the extremities to reduce heat loss (this is why your ears, fingers and toes get so cold so fast). The hypothalamus can also use muscle contractions and hormonal reactions to produce heat in the body.

Interestingly, the opah isn’t the only animal to throw a wrench in the gears of cold blooded classification. Dinosaurs, in case you didn’t already think they were awesome, defy conventional categorization and have forced scientists to create a third label “mesotherms” to explain how they regulated heat. The trouble with dinosaurs is that there aren’t any around to study, but by looking at growth rates compared to how much energy is burned in living animals, scientists have been able to piece together how  dinosaurs bodies might have worked. They lie in between cold bloodedness and warm bloodedness… More akin to tuna than lizards.

So once again the human urge to lump things into groups is thwarted by the complexity of nature. Just another reason why the guys who wrote the biology texts in the 19th century should have been more afraid of sharks and dinosaurs.

Tuesday, 19 May 2015

How to Find an Alien Race

To my mind, one of the coolest things that a basic understanding of science allows you to do is stare up at the night sky and imagine that somewhere in that mess of twinkling dots is another life form doing exactly the same thing. However, even mentioning the idea of aliens is enough to make a portion of people snicker and roll their eyes, but when you consider the probabilities at work in the universe the odds are on the side of believers.

One of the key pieces of the argument for the existence of aliens has long been the fabled Drake Equation created by astronomer Francis Drake in 1961 to help encourage investment in SETI (the Search for Extra Terrestrial Intelligence). The drake equation basically takes the huge number of planets and stars that we think exist and whittles it down to a conservative estimate of the number of alien civilizations. It takes into account six variables: the rate of star formation in the galaxy you are looking at, the fraction of stars that form planets, the number of planets that could support life, the probability that life actually emerges on one of these planets, the probability that intelligent life evolves, the probability that one of these civilizations develops a way to communicate with us and finally the length of time that a civilization like that is likely to exist.

Basically it is a lot of multiplying down that gives an estimate that there are around 12,000 civilizations capable of communication that should exist in our galaxy alone. So how can we find them?

The answer might lie in a combination of the laws of thermodynamics and something called the Kardashev Scale. The latter describes three types of civilizations that can exist at advancing levels of awesomeness. Civilizations are defined by the amount of energy they use and include:
  • Type I – Similar to Earth now. Some people have argued that Type I civilizations should be able to make use of all the energy produced by its planet (geothermal, wind, tidal energy, etc.). Based on that definition, humans have a Type 0.7 civilization, possibly reaching 1.0 in the next few centuries. 

  • Type II – Civilizations that can use all the energy produced by the star(s) at the heart of their solar system.

  • Type III – Civilizations that can use all the energy produced by their galaxy.

While it may be fun to imagine what life would be like at each level, all we really need to focus on right now is that each level uses an insane amount of energy compared to the level before it. The thing about energy is that is produces heat, and heat is something that we can see from very far away.

With that in mind, a group of scientists recently set out the find advanced societies across a section of the universe. Researchers at Penn State recently surveyed 100,000 galaxies using NASA's Wide-Field Infrared Survey Explorer (WISE) – a very fancy telescope. They looked at the heat signature from each galaxy and compared it to what you would expect if only natural processes were at work. The idea was that if a galaxy is hotter than you expect it to be, it might be because a civilization there is consuming a lot of energy. What they found was kind of scary…

Out of 100,000 galaxies, 50 where in the “hotter than expected” group. That is a very, very low number. Low enough that when they look at those 50 more closely, they could quickly become zero. If each of those galaxies is supposed to have 10,000ish advanced civilizations according to the Drake Equation, why are things so chilly? Either we aren’t looking at things in the right way or there might not be as much company out there as we thought. Maybe it’s just me, but that is a lonely thought.

Fortunately, it is fairly easy to join the “we don’t know what we’re doing” camp. Astronomers at Berkley are already hard at work looking for other signs of intelligent life and many people remain optimistic that we’ll find something… eventually. The other important thing to remember is that there could be life out there, it just might not be advanced enough to turn up the heat on its entire galaxy yet. It is even possible (although extremely unlikely) that humans have the most advanced civilization for light years around. We might eventually become the interstellar bullies we’ve made so many movies about.  

Friday, 15 May 2015

Sketchy Fact #91: Intergalactic Collision

Our Milky Way galaxy is in the process of colliding with the nearby Andromeda galaxy, which is approaching at  140 km per second. It is currently 2.5 million light years away and is the furthest object in the night sky you can spot with the naked eye.

Wednesday, 13 May 2015

Sinkholes: Nature’s most awful trick

It is easy to forget that the planet we live on is in many ways itself a living thing. Part of what makes the Earth so amazing is that it is one of the few places in the universe we know about that is geologically active. Internal forces churn magma, tectonic plates shift and crash into each other, volcanoes spew rock and ash sometimes with explosive force. The thing that these forces have in common is that they generally work slowly but surely beneath our feet before revealing themselves in some cataclysmic event – an earthquake, an eruption, etc. We can live with this because science (and a little common sense) lets us know where the danger zones are so we can avoid them or at least know about the risk. However, every once in a while the Earth quite literally pulls the rug out from beneath us.

Anyone who regularly watches the news has at some point seen footage of the geologic event known as a sinkhole and it probably boggled their mind. The picture is usually the same: a busy street in the middle of an urban area punctuated by a massive, seemingly bottomless hole in the ground, the black maw swallowing any light foolish enough to fall on it. Sinkholes that form suddenly to suck up a building or car are scary things. They often occur without much warning and if you are the unlucky sap driving over top when one decides to open up, there really isn’t much you can do about it.

Sinkholes form because of the layered nature of the Earth’s crust. Ask any kid with a shovel and they will explain that as you dig down into our planet, you will encounter various layers. To keep things relatively simple let’s focus on two key ones: the top bit we all know and love comprised of sand, soil, clay and the odd rock (occasionally and unceremoniously called “overburden”) and the layer of more solid rock beneath it called bedrock.

Bedrock can be made from any number of different types of stone, some extremely hard and tough and others that are more porous and relatively weak. Weaker forms of bedrock generally include things like salt, gypsum, limestone or dolomite. While you certainly wouldn’t want to bash your head against a piece of limestone, it is pretty wimpy in the world of rocks. Limestone and its kin are easily eroded by water that is even a little acidic. As water works its way through the ground is often absorbs chemicals like carbon dioxide that increase its acidity, allowing it to eat away at bedrock.

If you’ve ever explored a cave or been to the grand canyon you’ve seen what water can do to rock given enough time. Problems occur when the overburden on top of a layer of eroded bedrock has a little rigidity to it. Sometimes. seemingly solid ground we are walking, driving or building on is really just a soft cap covering a gaping chasm of nothingness. When enough weight is place on top of such a cap, or enough water flows through it to weaken it, the whole thing can come tumbling down.

But the really unfair thing about sinkholes is that they can sometimes form in places that we know are solid. One particularly awesome example of such an event is what happened in Louisiana at a place called Lake Peigneur on November 20, 1980. The thing about Lake Peigneur is that it sits on top of a massive salt deposit that is covered by a thin layer of soil. It also has some modest oil reserves. With that in mind, in November 1980 there were two industrial operations going on beneath the water: a salt mine and an exploratory oil drilling project.

Unfortunately, the team drilling for oil made a miscalculation about where one of the channels for the salt mine was. They drilled through the soil beneath the lake and right into the chamber where people were working. The men in the mine we barely able to escape before water started rushing in through the 14 inch hole the oil rig had created. Essentially they pulled the cork on the bathtub that was Lake Peigneur.

The thing about water, as we have learned, is that is can dissolve salt. As the water filled the salt mine it ate away at the walls, expanding the cavern. Over the course of a few hours the entire lake drained into the ground, pulling the surrounding Earth down with it. The canal that ran out of the lake into the Gulf of Mexico even changed direction, following inland and creating  a 150 foot waterfall (the biggest ever in Louisiana). The pressure and displaced air even created a 400 geyser. It was a scene out of the end of the world.

The vortex of draining water sucked up barges and fishing boats until enough water had been pulled in from the Gulf to equalize things, at which point everything that was sucked down popped back to the surface. Nowadays if you go to Lake Peigneur you can see the chimneys of houses that used to sit next to the lake poking out the salty water.

Keep that in mind next time to feel like you have your feet planted on solid ground. Sometimes it’s hard to know what lies beneath.

Friday, 8 May 2015

Sketchy Fact #90: A Breath of Fresh Air

A 30 meter tall tree can produce 2,721 kg (5,998 lbs) of oxygen in a year. Enough to support two people.

Wednesday, 6 May 2015

Getting the Coal Out: Scrubbing the air in Canada's most populous province

Canada has some pretty strong stereotypes associated with it. As residents of the Great White North, I and my partner in this illustrated science romp we call Sketchy Science have endured decades of ridicule, usually from our friends and neighbours to the south. In the end though, the stereotypes are often things to be proud of. Canada is usually depicted as an untamed wilderness of adventure and possibility. Unfortunately, like any other first world country, Canada is mostly an urban place. Sure our large land area and small population result in vast forests and mountain ranges, but that is largely because 81% of us live in cities.

The thing about those cities is that they are the perfect counterpoint to the nature we are known for. They are made of concrete and glass and are anything but pristine. Nowhere has that historically been more true than in the city of Toronto, also referred to as “The Big Smoke” because of its tendency to be so smoggy that the very young and very old are often warned to stay indoors. At least, that used to be true. For the past decade, changes have been underway in Canada’s most populous city (It’s not the capital. If you think it is, you have some Googling to do.) Actually those changes have been happening across the province of Ontario, and the results are pretty amazing.

Air pollution is a tricky thing to tackle. In a world where people treat their cars as members of the family and think of electricity as magic light that comes from holes in the wall it is tough to make a direct connection to the atmosphere and the air we breath. The truth is, it is all connected. Our cars burn gasoline and throw particles of soot, sulfur compounds and all kinds of other junk into the air (nevermind climate altering greenhouse gases). Even electricity contributes to the problem. Ontario may rely on hydroelectricity for a good chunk of its power, but historically coal was the name of the game. Coal power plants treat the air like a landfill.

The problem with air pollution is that it is terrible for human health. Research has shown that the common compounds found in the air of polluted cities can lead to minor upper respiratory irritations, chronic respiratory problems, heart disease, lung cancer, acute respiratory infections in children and chronic bronchitis in adults, aggravated pre-existing heart and lung disease, or asthmatic attacks. Even the rate of asthma has been climbing in North America as air quality has gotten worse. When we breath in heavy metals and volatile chemicals they react with the tissue in our lungs and throughout our bodies, causing inflammation and even impacting DNA expression.

It was with that in mind that politicians in Ontario made a bold move back in 2002. At the time, the province was home to 5 coal powered plants including the Nanticoke Generating Station, the largest coal plant in North America and the largest single polluter in the country, producing nearly 18 million tonnes of CO2 in 2007 alone. People in Ontario came together, put pressure on politicians to do something about the problem and the response was a commitment to close all of the province's coal power plants.

Over the next dozen years plants reduced their energy production and eventually shut down. At the same time, the province invested in cleaner energy like nuclear power, biofuels, solar and wind. In 2014 the last coal plant switched off its burners and the province was coal free. Since the phase out began, people have been waiting to see what the effect would be on air pollution.

They got their answer midway through April of this year when the Ministry of the Environment released it’s annual Air Quality Report. The research looked at four main components of air pollution (NO2, SO2, CO and fine particles that can get deep into the lungs) and found that the concentrations in the air had fallen between 30% and 46% over the previous decade. In 2014, Toronto had its first smog-free summer (0 smog alerts) in over 20 years. By contrast, Edmonton in the Canadian province of Alberta – where investment in coal power continues to grow – reported 25% poorer air quality than Toronto on its worst days despite having one-fifth the population.

The lesson in all this is that one single policy decision, supported by science can have a huge impact. Science and politics go hand in hand and the only way to build a better, healthier world is to rely on the evidence. Ontario is now working on passing legislation that will ban coal power in the province forever as they continue to invest in clean energy solutions. The future is looking bright in at least one part of the Great White North.

Friday, 1 May 2015