Sketchy Fact #53: Fighting Fingers

Your fingers don't have any muscles in them. When you move your fingers you are actually tugging their tendons using the muscles in your forearm.

Giant Boat-Knives and Other Bad Decisions: The Tale of the Basking Shark

Our friends at The Starfish asked us to drop some knowledge on basking sharks for Shark Week. Ask and you shall receive:

The ocean is full of monsters. That is a pretty well established fact. Any parent who has ever told an insomniac child, awake and trembling at 3AM, that there is no such thing has clearly never seen a picture of a giant squid or an angler fish. Sea monsters range from the very small (jellies) to the unfathomably enormous, but few are as impressive as the basking shark (known to science by the delightfully gladiatorial name of Certorhinus maximus).

Basking sharks fall into the “sea monsters” camp mainly because of their size. They are the second largest fish in the ocean (after whale sharks), reaching lengths of up to 33 feet and weighing as much as 8,000 pounds (3,600 kg). They also look unmistakably ferocious in that classic sharky way. They have dorsal fins that stick high out of the surface of the water, streamlined bodies, and (scariest of all) enormous mouths. You could swim into a basking sharks mouth pretty easily without ever touching the edges.

The thing about basking sharks though, is that they aren’t ferocious at all. Like so many of the biggest things in the ocean, they are almost comically gentle. They cruise around at around 3 mph (5 km/h) with their mouths agape, swallowing tiny plankton and filtering out massive amounts of water. They love to hang out in the sun right at the surface of the water, hence their name.

Unfortunately, this affinity for sunshine and their ridiculous size has caused some trouble between us and them, but not for the reasons you might think. Whereas humans normally hunt things as impressive as basking sharks for trophies or meat, these lumbering beasts are actually pretty useless as a commodity (unless you’re one of the 3 people alive who enjoy Icelandic hakarl).

The problem with basking sharks is that back in the 1940’s and 50’s they routinely got caught in fishermen’s gill nets by mistake. You may think that a basking shark would make a good catch for a humble fisherman, but the only sellable part of the great fish is its liver. I say “sellable” instead of “valuable” because in the mid 20^th century basking shark livers sold for 3 cents a pound (about $35 per shark) whereas the nets they destroyed with their massive bodies cost roughly ten times that much.

This inevitably led to fishermen hating basking sharks and complaining to the government. In 1949 the Canadian government gave in and labeled basking sharks marine pests and set to work at killing them. The method of choice was either ramming them with boats or slicing them in half with a huge makeshift blade mounted on the bow of a boat. In the 1950’s a giant boat-knife was an impressive thing, at least impressive enough to be featured in the November 1956 issue of Popular Mechanics magazine.

The giant knives proved remarkably effective and in a matter of decades basking sharks were nowhere to be found. Nowadays there is about one sighting per year off the British Columbia coast. Ask someone at the Department of Fisheries and Oceans where they went, and you will likely get a sheepish, embarrassed look in return.

However, the news isn’t all bad. In 2010, Canada followed the lead of countries like Ireland and Great Britain and declared the basking shark endangered. A recovery strategy was finalized in July 2011 and the people who once drove the knife-boats have since been at work mashing the ocean’s CTRL+Z key. Only time will tell if they’ve changed their minds in time.

Sketchy Fact #52: Ostrich Gaze

Ostrich eyeballs are bigger than ostrich brains.

The Alpha Myth: The Real Science of Wolf Packs

People and dogs have had an interesting and complicated relationship since the dawn of civilization. Ever since the first wolf worked up the courage to take food out of a person's hand our two species have been trying to figure each other out. We have moulded the original overly-tame wolves (and yes, all dogs are descended from wolves) into hundreds of different dog breeds of all shapes and sizes. We know which dog to call on to herd sheep, the best for hauling in fishing lines, and which dog to put front and centre in a fire engine. However, for everything we know about the dogs we have created; we have been historically deficient in knowledge of the animals we have left behind.

Considering how much we love dogs, wolves have had a surprisingly rough go. Throughout history people have grown to fear wolves and have hunted them to the brink of extinction. Flip through any animal-based fairy tale book and you will find a disproportionately large number of stories featuring wolves as villains. We have been happy to think of wolves as ruthless killers, ignoring the fact that they are essentially just bigger, more skittish dogs that are trying to make an honest living in the wild.

If you don’t believe that we have been wilfully ignorant of wolves until very recently, consider the fact that the one thing that most people know about wild wolf packs is blatantly wrong. Ask the average person about the social structure of a wolf pack and you will likely get a vague explanation involving the Greek letters alpha and beta. Alpha wolves are the pack leaders; they lead the hunt and keep the betas in their place. They eat first, breed first and are the kings of the castle. The trouble is, they don’t exist.

The alpha wolf theory is based on an observational study undertaken in the 1940’s by biologist Rudolph Schenkel. The theory gained popularity in the 1970's when L. David Mech published his book The Wolf: Ecology and Behavior of an Endangered Species. Unfortunately, most scientists (including Mech himself) know that they alpha theory is based on faulty extrapolation. Mech has actually been trying to get the book out of print for a number of years. 

You see, when Rudy Schenkel was watching wolves and making notes, he overlooked one important fact: the wolves he was studying were in captivity. Their pack was not the kind that formed naturally in the wild; it was made up of adult wolves forced to live together and compete for resources. Not surprisingly these wolves fought a lot and the dominant ones got their pick of food and mates. This study has been compared to learning about the behaviour of human families by observing people living in refugee camps. 

In truth, when a male wolf meets a female wolf, they mate, and they raise their offspring together. A pack is just a family. When the offspring get old enough, the males leave to find mates from other packs and start the cycle over again. There are no alphas and betas, only parents and children. Occasionally packs will come together to hunt a particularly large animal or take advantage of a concentrated resource, but usually a pack is just a family unit with older offspring rotating out as new ones are born.

This simple revelation has had dramatic consequences for the way people think about training dogs. Generally speaking, people fall into either the dominance camp or the positive reinforcement camp. Unfortunately, when you stop talking about wolves and start talking about dogs, emotions run a lot hotter. No one wants to believe their method of training is cruel, but that is the word that tends to get thrown around. We won't branch out into the world of offering dog training advice. The message we want you to take away from all of this is that things are generally more complicated than they appear, and that wolves are actually a lot more peaceful than you have been led to believe… But you still shouldn't get up in their space… Unless they raised you.

Sketchy Fact #51: Finger Licking Good

Your spit contains a chemical called Opiorphin that kills pain as effectively as morphine. That’s why you reflexively suck on paper cuts and the like.

Talkin’ bout Regeneration: Why can’t humans regrow limbs?

The life of a seastar (read: starfish) is a pretty enviable thing. Aside from the artistically inspired body plan, seastars get to spend their days relaxing in the ocean, enjoying the ebb and flow of the tides. They watch all manner of interesting marine life pass by overhead without ever having to worry about jobs, bills, or crooked mechanics. However, if I had to pick one thing from a seastar’s life to really get jealous about it would have to be the ability to regrow limbs.

If, during their care-free oceanic existence, something comes along that wants to make a meal out of them seastars don’t have a lot of options. They are hardly built for speed and camouflage isn’t exactly in their wheelhouse. However, if something does get a hold of them, they have the ability to detach one of their limbs and hopefully escape with the other four. Over a period of a few months or up to a year or so they can regenerate the lost limb. Not only that, the limb they left behind (if it somehow managed to escape becoming octopus food) can regrow the rest of it’s body and form a second, genetically identical seastar.

Seastars are hardly alone in this ability. Earthworms, salamanders, snail firs, some fish, and even the occasional mouse have been known to regrow complete or partial limbs. Seastars often go one step further, though by voluntarily detaching their own limbs to reproduce asexually when lady seastars are not being especially receptive to their advances.

So what’s the deal? Why do all these other animals have this clearly convenient ability while us humans are left twiddling our phantom thumbs? Well, first off, we aren’t totally outside the club of regenerative species. Many children have lost the tips of fingers or toes only to turn up at the doctor’s office a few months later with everything back in place (minus fingerprints). The interesting thing in each case where this happens is that when the fingertip was cut off some of the nail bed was left intact; and it is this fact that gives some insight into how regeneration works.

It seems that to regrow body parts, the bits that are left behind in the wake of a serious injury need to know how to communicate. If you’ve ever tried to explain to someone how to build something specific out of Lego without actually doing the work yourself, you can begin to understand how challenging communication can get in the world of construction. At the cellular level, communication falls on the shoulders of stem cells left at the site of an injury. Scientists have discovered two kinds of stem cells that do this work: somatic stem cells and pluripotent stem cells. Unfortunately, in the world of limb regeneration, not all stem cells are created equal.

Somatic stem cells can close a wound, regrow some skin, and fill in the gaps with scar tissue but not a whole lot else. Pluripotent stem cells are the real professionals. They send signals known as Wnt communications throughout the body, getting bones and even nerves involved in the healing process. These are the cells that allow structures to reform. The bad news for humans and most other mammals is that, outside of the time we spend in our mothers’ wombs, we don’t get too many pluripotent stem cells. In fact, most of the ones we are left with by the time we are born are in our hair follicles and our fingernails... It’s all starting to come together now.

Scientists aren’t exactly sure why mammals seem so deficient in what are obviously handy (no pun intended) bodily resources. Some believe that our fast metabolisms that require constant food preclude us from hiding in a dark cave for a year while our limbs regrow. Instead we have to stop the bleeding and get back to hunting as soon as possible. Others believe that the complex body plans of mammals are too complicated to be regenerated in the same way that seastars' body parts can be.

A few optimistic souls say this might just be a temporary state of affairs. Sometime in the next few decades we may unlock the chemical communication secrets of pluripotent stem cells and set to work regrowing our own body parts. However, until that day comes, I wouldn’t get too close to any wood-chippers.

Sketchy Fact #50: Visiting the Neighbours

If you wanted to travel to the closest star to Earth (other than the sun) on the fastest space vehicle humans have ever built (240,000 km/h on Helios 2) the trip would take you 19,000 years. All the road-bingo in the galaxy wouldn’t make that trip bearable.