Upcoming 'Shark week' rant

And so, once again, Shark week is almost upon us in Canada. Hooray! Sharks, after all, are magnificent and powerful creatures, alpha predators of the oceans, just as big cats or bears are on land, and crocodiles and alligators are in fresh water.

Sharks are very varying creatures. For example, both the whale shark and the basking shark are filter feeders, but whereas the basking shark just swims around with an open mouth, with the water flowing in and out (through the gills), the whale shark actively pumps the plankton-filled liquid and in general is a more active fish among the two. The megamouth shark, which is also a filter feeder, does its own thing by actively feeding on plankton at night, when its competition (including the baleen whales) is asleep. 

The carnivorous sharks, of course, are an even more diverse group. The great white shark is Jaws, one of the most powerful denizens of the ocean; only the killer whale (and perhaps the sperm whale) can defeat it. The bull shark is smaller, but still very solidly built, and is one of the few fish that can live both in fresh and salt water. The sand tiger shark (no relation to the actual tiger shark) and the blue shark, on the other hand, are graceful inhabitants of the open waters, specializing in catch fish, not warm-blooded mammals and birds, as the great white shark does – and the list goes on.

Some of the sharks are downright bizarre – the aforementioned thresher shark with its remarkable tail; the hammerhead shark with its head; the sawnose shark which is similar to the better-known sawfish because it also has a saw on its nose – etc. All of these features make sharks stars of the ocean world – and of the Shark week that will be airing on the Discovery channel starting from August 10. 

Sadly, there is a rather big fly in the ointment, and it is called “Megalodon: The New Evidence”. It is a sequel to the previous mocumentary, “Megalodon: The Monster Shark Lives”. That particular film played with the concept of Megalodon surviving in modern times, feeding on such animals as the humpback whales...and for a while it led many people astray, by making them think that this was a real documentary instead.

Now, in part this is his or her own fault – one should not be so gullible about what one sees on TV or the Internet...never mind. I need to go a make an appointment with my vet about the health of my unicorn that I have bought on EBay. That is an old story. The thing is that Discovery channel generally airs documentary films and series, which are based in real life; even on such specials as Shark week what we usually see are documentaries; the Megalodon duology (and before that – the duology about the mermaids) are not – they’re fiction, just like the Sharknado or the Mega-Shark films are.

Now, Discovery channel currently does not have it as bad as the Animal Planet, by comparison; they still do not regularly air such tripe as “Man-Eating Super Wolves” or “Zombie Cats”, etc. But this is a disturbing tendency all the same.

If we are talking about sharks, what about Megalodon itself? Can it still be real? No. Sharks do not readily leave remains, other than their teeth and the occasional backbone vertebra, but their teeth quite take up the slack, and people find them very often. Megalodon teeth in this case take a very specific position: they are fossilized, not fresh. There are no fresh Megalodon teeth, which means – that there are no live Megalodon sharks living in modern oceans. Giant sharks, on the other hand, are a different story – in general, cold-blooded animals tend to grow throughout their lives, and great white sharks, in particular, can reach 3, or even 4.5 m in length: still smaller than Megalodon was, but far bigger than a human is. This is more than enough to fill-in Megalodon’s econiche.

And what econiche is that? That of a mega-predator, of course. Megalodon was the biggest shark of all times, of course, but it was also a part of the mega-fauna of the previous Cenozoic epochs. During that time, most animals were larger than their current relatives are, and the same goes for the sharks.

Speaking of relatives, there is some speculation that Megalodon might be related to the mako sharks. While the great white shark evolved into a powerhouse, the mako (two species) evolved into the aquatic analogue of the cheetah (sort of) – it is the only fish fast enough to catch and kill the legendary swordfish. Real life being what it is, however, sometimes the swordfish is the one who comes on top and dead or dying mako sharks were found, with pieces of the swordfish’s sword still in them – but that’s not the point. The point is that some scientists believe that Megalodon was more closely related to the mako than to the great white, and others – that the mako is the close relative of the great white, and Megalodon is related to neither, and if we don’t even fully know to whom Megalodon was related to, then how do we know what it looked like? Any depiction of the Megalodon is fully speculative, period – maybe it looked like a giant bull shark instead, who knows...

Back to the econiche. The great white shark has taken over Megalodon’s place – to a point: it still does not attack and eat whales. But it does not need to – the killer whale does it instead. Smarter and more social than any shark, even the great white, the killer whale does an admirable job of killing baleen whales, sharks, giant squid and other denizens of the oceans. Not bad for a relative newcomer to Earth – just like humans, the killer whale is very much a modern animal.

The shark, on the other hand, is very old – they have been around roughly since the Devonian, over 300 million years ago in the past, and they were able to handle everything that the Earth, and the universe, threw at them. Lately, this includes humans, who kill many more sharks than sharks kill people. To paraphrase Josef Augusta, a famous paleontologist, ‘the hunter man of the Pleistocene had little impact on nature, unlike the gatherer man of the Holocene’. These are true words, and hopefully, the upcoming Shark week shall discuss them as well.

End