Whale Fall – More than just a hilarious existential crisis

Whale fall. It may sound like the rejected title of a James Bond movie or a Douglas Adams reference, but it is actually a surprisingly important and relatively little known concept in the study of the world’s oceans. It all begins with one of the saddest moments in the story of any whale family. Grandpa whale, let’s call him Moby, after a long a fulfilling life of eating ship captains’ legs, dies. 

As sad as this is for the rest of the whale family, odds are that if Old Moby died from natural causes he lived a pretty long life. Research beginning in the 1990’s revealed that a significant portion of the population of many whale species is over 100 years old. Questions started being asked when whale carcasses were pulled from the ocean containing stone harpoon heads, which fell out of fashion around 1860. Tissue samples from a group of Bowhead whales subsequently revealed that several were in their mid-100’s and one male was pushing 200. The point is whales can live a long time.

When a whale dies without human intervention its body either washes up on shore, occasionally with hilarious consequences, or it sinks to the bottom of the ocean. The latter is much more common and the result is something pretty remarkable.

When a whale fall, as these things are known, touches down the animals that live on the sea floor throw a party. The deep ocean is a surprisingly poor environment in terms of available food and energy with animals living mostly on small particles of so-called “marine snow” that drift down from above or by eating each other. A whale carcass, as you can imagine, is a welcome break from this kind of life.

The first phase of a whale fall food chain involves getting all that delicious, rancid flesh off the bones. That job is taken care of by animals like ratfish, sharks, crabs, and hagfish. The work goes surprisingly quickly. These scavengers can liberate up to 60 kg (132 lbs) of meat in a day. After a few short months (whales are big animals) only a skeleton remains. At first glance it would seem like the show is over, but in reality things are just heating up.

As the crabs and sharks pack up and move on to greener pastures, worms move in. Lots of worms. Polychaete worms, to be precise. Up to 45,000 worms per square meter blanket the sea floor about one year after the whale buffet opens its doors. They, along with a few other species of invertebrates, feast on the organic material in the whale bones. Although this stage of whale decay brings huge numbers of animals, they represent only a few species. The real fun begins when the microbes arrive on the scene.

Somewhere between one and two years into the show, most of the low hanging fruit (to use a more pleasant sounding metaphor) has been harvested. At this point sulphur-reducing bacteria arrive to feed on the fats and oils left in the skeleton. As they do this they release sulphur into the surrounding water, which attracts sulphophilic (sulphur-loving) bacteria. These bacteria, remarkable, form the basis for a very unique food web.

Most food webs on Earth begin with photosynthesis as plants turn sunlight into food. The web around this stage of a whale fall by comparison is chemosynthetic, meaning that it’s basis is chemical reactions by bacteria. Larger and larger animals feed on the bacteria and on the creatures that feed on the bacteria until eventually you have a booming community that includes up to 190 different species of visible animals. The only other place where this type of system exists is around deep sea vents where the energy comes from within the Earth itself.

These Stage Three whale fall communities can last a surprisingly long time. We're talking decades. Research has shown that some whale falls can sustain an ecosystem for over 50 years! And these are not rare systems. Given the number of whales alive today and the length of time that these communities last, scientists estimate that there may be a whale fall every 5 to 16 km (3 to 10 miles) along the sea floor, meaning that when the nutrients finally do run dry, the creatures that depended on them don’t have far to travel until they find their next home.

Whale falls are islands of biodiversity in one of Earth’s least bountiful places. Yet another reason why humans should do our part not only to protect whales, but to protect the fish and oceans that they depend on. 

Sketchy Fact #95: Cruisin' for a Bruisin'

The changing colours of bruises is a result of your body breaking down and reusing the hemoglobin in spilled blood cells. Hemoglobin is broken down into a green pigment called biliverdin. Biliverdin is broken down into bilirubin, which is a golden brown colour.

Sloppy Science: Why does alcohol get you drunk?

Few substances have as long and strange a history with the human race as the collection of liquids we call alcohol. For about as long as humans have been living together in large groups we have been consuming, fighting over, and occasionally procreating as a result of what is basically a low-grade poison.

The alcohol that we know and love (found in beer, wine, hard liquor, etc.) is called ethanol and it may disturb you to know that it is actually the waste produced by unicellular fungi called yeast. Yeast loves to eat/react with sugar, and when that happens ethanol and carbon dioxide are expelled. Humans make use of both of these products. When you bake a loaf of bread it is the carbon dioxide bubbles that make it rise as the alcohol is evaporated away. In beer, the same carbon dioxide produces fizzing as the alcohol primes you for karaoke.

The amazingly simple chemistry and minimal ingredients involved are the reason why many researchers believe humans were drinking wine 3,000 years before we invented pottery or the wheel. Yeast thrives on the skin of fruit and when that fruit starts to decay the yeast gains access to the sweet sugars within. Half-rotten fruit (especially grapes) is basically booze waiting to happen. It wouldn’t have taken much for Neolithic people to put two and two together and start serving fermented grape juice (AKA wine) with their mammoth steaks at dinner parties.

But why do we love alcohol so much? To answer that question you need to understand what happens when ethanol gets into your body: When you drink alcohol it makes its way through your stomach into your small intestine, where nutrients are absorbed by the blood. Ethanol isn’t much of a nutrient but it can still hitch a ride on your blood cells to any tissue in your body that contains water (they all contain water). Your brain in particular is a veritable paradise for the stuff. Alcohol is processed by the liver and kidneys and broken down/removed from the body at a rate of about an ounce per hour, it is also a diuretic, meaning it makes you pee a lot, but when you drink more than your body can process ethanol starts to build up in your tissues. That’s where the fun begins.

In your brain, ethanol slows things down. That is why we call it a depressant. Your brain contains different neurotransmitters, some activate parts of your brain (excitatory neurotransmitters) and others de-activate parts of your brain (inhibitory neurotransmitters). Alcohol stimulates the release of GABA (gamma aminobutyric acid) which is inhibitory and it prevents the release of glutamate which is excitatory. The influx of GABA turns down the parts of your brain that control inhibition, making you say and do things you would otherwise consider a bad idea. At the same time the parts of your brain that control reaction times, balance and coordination also get dialed down, making you clumsy and a bad driver. Too much alcohol can even turn off the parts of your brain that remind you to breath or gag, an effect that has robbed the world of many a great musician. We call this “alcohol poisoning.”

But beyond all of this flipping of dimmer switches, alcohol results in a flood of the neurotransmitter dopamine in your brain’s reward centres. The same thing happens when you win a hand of blackjack or steal a kiss from someone you like. It is addictive. That is what makes alcohol dangerous.

In the short-term, processing alcohol is a drain on your body’s water resources. As your body tries to flush your system through constant peeing and your liver uses even more water to break down ethanol, other parts of your body get dried up, including your brain. That is why you often feel so rough the next day. You brain has literally shriveled up and the tissues throughout your body cannot work how they are supposed to. Other important chemical balances like the level of potassium in your blood also get out of whack. Over the long-term, your liver is damaged by repeated exposure to the waste products released as ethanol is broken down. Your liver is a pretty important organ if you like being alive.

There is some evidence that a single beer or glass of wine per day may have long-term health benefits for some people, but that just speaks to what the role of alcohol should be in anyone’s life. As with most things that you end up craving, the name of the game is moderation. 

Sketchy Fact #94: Kurt Vonnegut vs. The World of Science

Scientists recognize 16 different types of ice that form under different atmospheric pressures and temperatures. The stuff in your freezer is Ice IV.

Allergies: Why Your Body Hates You

Billions of years of evolution have crafted your body into a high octane, fuel burning, disease fighting machine. There are so many processes going on in each of the quadrillion-odd cells that you are made of that scientists are only beginning to scratch the surface of basic things like nutrition and diet. However, just because your body is impressive doesn't mean that it is perfect. Occasionally, for some of us, the actions our bodies take to keep us alive can lead to intense discomfort or even death. The best example of this type of mishap is allergies.

In the world of medicine allergies are referred to as an autoimmune disease, meaning that the immune system that is meant to fight of invading parasites and viruses mistakenly attacks a person’s own body. They occur in roughly 10% of people (slightly more in developed countries, but we’ll get to that) and lead to a cascade of bad times for sufferers.

Becoming Allergic

The way allergies work involves a couple of crucial steps that are better explained in fun, cartooning sketches than paragraphs of text:

First, some new material enters the body where immune cells (the police force of the body) suspect it is up to something fishy. This is known as the "sensitizing exposure" and means that the first time an allergic person comes into contact with the thing they are allergic to, nothing happens.

The immune cells report back to the lymph nodes (their police HQ) and tell the body to produce antibodies (AKA immunoglobulins) to fight off the invading material, also known as the antigen, in the future. (Thank you to the readers who caught our mistake, switching antibodies and antigens)

The antibodies (specifically one called immunoglobulin E – IgE for short) attach to “mast cells” throughout the body where they begin a stake-out for the suspicious material.

The next time the new material shows up in the body, it is attacked mercilessly by antibody-clad mast cells. This is the equivalent of activating the army, navy, special ops and coast guard against girl guides trying to cell cookies.

When mast cells attack their targets, the effects on the body can be pretty terrible. Chief among them are the dilation (expansion) of blood vessels and the flooding of the area between cells with fluid. Dilated blood vessels lowers blood pressure and can starve organs of the oxygen they need to function. Fluid between cells causes swelling which can make you look like a puffy, lumpy version of yourself in addition to closing your throat so you can’t breath. The areas of the body with the most mast cells (skin, nose, throat, intestines, etc.) tend to be hit the hardest.

The Hygiene Hypothesis

So if allergies are so clearly bad for us, why hasn’t evolution naturally selected against them? The question is actually a surprisingly hard one to answer. The truth is, no one knows; but there are two main schools of thought.

First is the idea that allergies are a reaction that benefited our bodies in the recent past. Specifically, a lot of researchers think that allergies are meant to protect us against parasitic invasions. However, since parasites are a less common component of our diets than they used to be our bodies end up overreacting and freaking out when we breath in pollen instead.

Alternatively, there is the idea that putting ourselves in a protective, germ-free bubble for the early part of our lives has compromised some children’s abilities to develop fully-functioning immune systems – the so-called Hygiene Hypothesis. Basically the body isn’t exposed to as wide a range of microbes as in was in generations past, but it still expects to be. The long wait between attacks makes your immune system paranoid it starts labeling harmless things like peanuts, pollen and shellfish as terrorists. This could explain why allergies are more common in developed countries and are on the rise in rapidly developing nations.

If you suffer from allergies, the best treatment is avoidance. If your allergies are severe and sneaky you might need to carry an epi-pen, which is a shot of epinephrine that constricts your blood vessels and opens your airways. Epinephrine is produced naturally in the adrenal glands and is usually not called into action unless you need to run away from a lion or something. Alternatively, if you love the thing you are allergic to (ex. your dog), you can try immunotherapy which attempts to build up a tolerance through increasingly potent injections of the protein you are allergic to. If you have a food allergy, sometimes cooking the food can destroy the protein that causes the reaction (as is the case for our illustrator with carrots), but this is not something worth experimenting with if you are hyper-sensitive.

The important thing to remember is that we are still learning about allergies. New research is leading to new discoveries, but we still don’t know everything. With that in mind, take things like the hygiene hypothesis with a grain of salt. In short, we don’t know enough for you to leave your baby in a tepid pool of pond scum… yet.

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.”

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 19^th century should have been more afraid of sharks and dinosaurs.