Given that we are in high summer now, and the crazy world of business simmers a little more gently than usual, I think a little biological distraction is perfectly acceptable. Summer just wouldn't be summer without "Shark Week", courtesy of the Discovery Channel, and this year was no exception - for what felt like 24/7, we were bombarded by stories both real and mythological featuring these magnificent eating machines of the deep blue. I think they tag it as "The most wonderful week of the year", which is perhaps an exaggeration for some, if not downright hilarious for many, but no matter, Shark Week remains a killer close-up look at some very impressive biology!
I mean, who could resist such episode titles as "Monster Mako" and "Return of the Great White Serial Killer" and "Sharksanity", or even "Bride of Jaws" - featuring the legendary "Joan of Shark" - a mammoth female great white weighing in at over 3,000 pounds and almost 20 feet in length? It's one of those rare occasions where kids and parents alike gather on the sofa with equal excitement, salivating at the very thought of seeing a great white chew off the back end of a boat as a dinner starter.
Sharks are by no means recent inhabitants of planet Earth, having been with "us" for not far off 500 million years, although the various species commonly identified today as "sharks" seem to have evolved over the last 100 million years or so. That still makes them evolutionary superstars that have survived four major mass extinctions on the planet, with no disease or infectious agents that seem capable of penetrating their thick skin. One thing that fascinated me since high school biology is the capacity of certain sharks (such as the bull shark) to adapt their biochemistry to survival in both salt water and fresh water, and if that's not a neat trick I don't know what is! As brilliantly evolved as sharks are, their existence has been most significantly dented and threatened in recent history by the usual suspects - mankind.
Of course, mankind! In fact, commercial fishing and marine-related industry in general in just the 20th century has been estimated to have decimated the population of the ocean's largest predators by as much as 80%, which seems reminiscent of our effect on similarly dominant large predators, in the jungle. Historically, when we come across something significantly bigger than us and innately more dangerous by nature of their evolutionary gifts, well, we are scared of them and use our significantly larger brains to find a way of eliminating them. I suppose some would call that evolution and Darwinian natural selection too, after a fashion, but it sure feels more like ecosystem obliteration if not intentional extinction a lot of the time.
Sharks do have a bad rap of course, not least because they are on record as supposed ruthless maneaters who terrorise us at every opportunity, but you know, if we were to go running around the jungle in our boxer shorts or bikini, what would we expect to happen? That somehow seems more acceptable than swimmers or surfers being attacked in territory that humans like to regard as theirs - the ocean. But it's not because we place a few nice sandy beaches on the water's edge that the ocean somehow becomes ours; the very fact that sharks such as the great white are around today is testament to the fact that the ocean is very much theirs, and not ours.
These giants of the deep are predators at the very top of the food chain, and they don't need to sail around in hulking big boats with harpoons and other weapons to feel safe. While their exact correlation of mankind with tasty seafood remains misunderstood or even contentious, it seems remarkably easy to understand how they could mistake a body splashing on a surfboard above them with a seal in the water, and once bitten, well, blood is blood - and we all know how sharks react to that smell and taste. It is probably true also that many of the attacks on humans come from sharks that are ravenous and have not recently bitten the rear off a killer whale for lunch, so, as scavenging predators and opportunists, they bite whatever comes their way even if that includes a steel cage with divers in it!
The bottom line is that if we were not splashing around in their environment then there would and could not be any attacks on humans. Further, if they were not currently under the evolutionary pressure that we are applying on them, they perhaps would not appear so far inland at our beaches looking for food, with an axe to grind on humankind. But like us, they will always be prone to making mistakes, snapping off a bit of surf board and getting a sliver of sinew and blood along with it, and the rest will be history, usually. It's simply their nature, and we are modifying their nature, clearly, with some unpleasant results.
That we are so far from the top of the food chain in the water is underlined by the video below which is from this past week (right on cue for Shark Week Fever!) and gives us all an idea of how a fun day splashing in the water can turn potentially ugly, and fast. Australian Mick Fanning is vying for his fourth world surfing title and was competing at the World Surf League competition in J-Bay, South Africa, when out of the blue (literally!) something sinister appeared behind him. It truly was a horrifying few seconds, even for us, and when he seemed to have disappeared below the water just after the first exchange, well, it looked like it was all over. Thankfully not, and the crowd jumped up and down when they saw him swimming away from his board to safety.
I mean, who could resist such episode titles as "Monster Mako" and "Return of the Great White Serial Killer" and "Sharksanity", or even "Bride of Jaws" - featuring the legendary "Joan of Shark" - a mammoth female great white weighing in at over 3,000 pounds and almost 20 feet in length? It's one of those rare occasions where kids and parents alike gather on the sofa with equal excitement, salivating at the very thought of seeing a great white chew off the back end of a boat as a dinner starter.
Sharks are by no means recent inhabitants of planet Earth, having been with "us" for not far off 500 million years, although the various species commonly identified today as "sharks" seem to have evolved over the last 100 million years or so. That still makes them evolutionary superstars that have survived four major mass extinctions on the planet, with no disease or infectious agents that seem capable of penetrating their thick skin. One thing that fascinated me since high school biology is the capacity of certain sharks (such as the bull shark) to adapt their biochemistry to survival in both salt water and fresh water, and if that's not a neat trick I don't know what is! As brilliantly evolved as sharks are, their existence has been most significantly dented and threatened in recent history by the usual suspects - mankind.
Of course, mankind! In fact, commercial fishing and marine-related industry in general in just the 20th century has been estimated to have decimated the population of the ocean's largest predators by as much as 80%, which seems reminiscent of our effect on similarly dominant large predators, in the jungle. Historically, when we come across something significantly bigger than us and innately more dangerous by nature of their evolutionary gifts, well, we are scared of them and use our significantly larger brains to find a way of eliminating them. I suppose some would call that evolution and Darwinian natural selection too, after a fashion, but it sure feels more like ecosystem obliteration if not intentional extinction a lot of the time.
Sharks do have a bad rap of course, not least because they are on record as supposed ruthless maneaters who terrorise us at every opportunity, but you know, if we were to go running around the jungle in our boxer shorts or bikini, what would we expect to happen? That somehow seems more acceptable than swimmers or surfers being attacked in territory that humans like to regard as theirs - the ocean. But it's not because we place a few nice sandy beaches on the water's edge that the ocean somehow becomes ours; the very fact that sharks such as the great white are around today is testament to the fact that the ocean is very much theirs, and not ours.
These giants of the deep are predators at the very top of the food chain, and they don't need to sail around in hulking big boats with harpoons and other weapons to feel safe. While their exact correlation of mankind with tasty seafood remains misunderstood or even contentious, it seems remarkably easy to understand how they could mistake a body splashing on a surfboard above them with a seal in the water, and once bitten, well, blood is blood - and we all know how sharks react to that smell and taste. It is probably true also that many of the attacks on humans come from sharks that are ravenous and have not recently bitten the rear off a killer whale for lunch, so, as scavenging predators and opportunists, they bite whatever comes their way even if that includes a steel cage with divers in it!
The bottom line is that if we were not splashing around in their environment then there would and could not be any attacks on humans. Further, if they were not currently under the evolutionary pressure that we are applying on them, they perhaps would not appear so far inland at our beaches looking for food, with an axe to grind on humankind. But like us, they will always be prone to making mistakes, snapping off a bit of surf board and getting a sliver of sinew and blood along with it, and the rest will be history, usually. It's simply their nature, and we are modifying their nature, clearly, with some unpleasant results.
That we are so far from the top of the food chain in the water is underlined by the video below which is from this past week (right on cue for Shark Week Fever!) and gives us all an idea of how a fun day splashing in the water can turn potentially ugly, and fast. Australian Mick Fanning is vying for his fourth world surfing title and was competing at the World Surf League competition in J-Bay, South Africa, when out of the blue (literally!) something sinister appeared behind him. It truly was a horrifying few seconds, even for us, and when he seemed to have disappeared below the water just after the first exchange, well, it looked like it was all over. Thankfully not, and the crowd jumped up and down when they saw him swimming away from his board to safety.
While much remains misunderstood about shark behaviour, the one thing that is crystal clear is that if we get in their way in open waters, they will do what their 100 million years worth of evolutionarily honed genes have taught them to do - eat. That it is us and not a baby seal is probably of no consequence to a king of the food chain such as a great white, and as much as many despise them, they are only doing what humans have been doing since the beginning of time - killing other animals for food on which to survive. It is something each of us does basically every day, whether we are in denial about that or not. I guess we have become so used to thinking of ourselves as top of the food chain, that we resent greatly being occasionally reminded that we are not!
In any case, given their clear ferocity in the water, mankind and sharks have a not-so-friendly relationship most of the time, but they are incapable (to date) of invading our territory so we are in no danger from them - until we invade theirs. Doing so for research purposes has greatly increased our understanding of these still mysterious creatures, and it forms the basis of the hugely entertaining "Shark Week" each year, for which you will hear no complaints from me!
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