Science is pretty damn awesome. For starters, it’s proven rather good at providing us with all kinds of nifty stuff: like the electronic device you might be reading this on, or the breakfast you had this morning, or the beer you drank way too much of last night. Probably, some of you are screaming at me right now: “Ah, but Mr. Author Person Guy! My beer’s not science! Science is, you know, quantum physics and biology and chemistry and computers and that kinda stuff!”
But what is science, if not the pursuit of knowledge? What else is science than ordinary people wondering about the silliest things? “I wonder what would happen if I try to make a drink out of this spoilt cereal?” “What happens when I smash my proton into another proton at nigh the speed of light?” “Why does the sun rise?” “Why did the dinosaurs die out?” “Why should I never kiss a shark?” See, every time you ask a question, you are doing science.
I am, in the words of Albert Einstein, passionately curious. I am amazed every day by the exquisite beauty of this insanely absurd universe we live in. I have a passion for science, a passion for understanding things, and a passion for other people who are as wizened by our strange world as I am. And I’m here to share my love for science with you, and to hopefully ignite a tiny spark of passionate curiosity in you. I won’t pester you with rigorous mathematics, required literature or homework exercises. I will be relentless, however, in trying to show you cool, science-y things you didn’t know before. Today I’ll share a thing or two about sharks, and you’ll get to see how they are both really awesome and really weird; as you’ll find out in short notice, these things are typically intertwined in my worldview.
But first, let’s talk about bones (don’t worry, I’ll get to the sharks in a bit). Bones are pretty useful: they give your muscles something nice and sturdy to attach to, and help our bodies to not look like silly meat-pudding. A very large portion of all animals have bones, like almost all fish, mammals, birds and reptiles, and the fact that bones are present in such a large variety of species proves that they’re typically good for survival rates. So how come sharks don’t have them?
Wha-? That’s right. Sharks, in fact, do not have bones. Not in the traditional sense of the word, at least. That’s because, together with rays and skates, they make up the group of cartilaginous fishes. This signifies that their ‘bones’ are actually not made of bone at all, but of cartilage, the stuff that gives your ears their structure! So how is it that a creature so primitive that it doesn’t even have proper bones is at the top of the food chain?
Actually, a shark’s fake bones probably help it to stay on top: cartilage is lighter and more flexible than bone, which provides the shark with much greater maneuverability. So why don’t we all have these cartilage bones, then? As I mentioned, our bones provide a more sturdy structure for our body, and allow us to attach our muscles to something nice and tough. While cartilage bones do certainly have their benefits, it seems that through the course of time ‘normal’ bones provided enough advantages that they have largely prevailed. We don’t know of any land animals with cartilage bones either, so the fact that sharks live in water probably helps, as well.
A final interesting thing about the cartilaginous fishes is that they split off from other fishes before the development of scales. Sharks have, however, proven themselves to be rather good at producing teeth. That’s right: a shark’s ‘scales’ are actually made of dentin, just like your teeth; which means that sharks are, in fact, covered in millions of tiny teeth. Which is precisely why, dear reader, I wouldn’t advise you to kiss a shark. You know, besides the obvious ‘it might eat your face’.
Despite how gloriously cool sharks might be, they do face a tiny bit of a problem: us. You see, we humans have proven to be rather good at killing sharks. In fact, official numbers state that we kill over a hundred million sharks each year. This is due in large part to the famous shark fin soup, although their poor reputation (I’m looking at you here, Jaws) also plays its role. This mass killing has resulted in over a quarter of shark species being currently endangered, or worse. I, personally (and hopefully all of you lovely readers too), would be pretty sad to see sharks become extinct. So let’s keep the sharks, in all their glorious teethyness, out of our soup, and in the ocean. They’re pretty damn cool, and far from as dangerous to us as we are ourselves.
Sources:
http://www.sharkproject.org/haiothek/index_e.php?site=gefahr_10
http://statline.cbs.nl/StatWeb/publication/?VW=T&DM=SLNL&PA=7233&LA=NL
https://www.youtube.com/watch?v=U4b-Mv_3e4U&list=UUZYTClx2T1of7BRZ86-8fow
http://en.wikipedia.org/wiki/Chondrichthyes
http://www.ias.ac.in/jarch/jbiosci/22/431-437.pdf
http://elife.elifesciences.org/content/3/e00590
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