Now Sea This: The 10 Most Amazing Bizarre Sharks
Strange, scary and sharp of tooth, sharks are the oceans’ most efficient predators. They’re much more than “mindless killing machines”, however, as these ten bizarre sharks so graphically illustrate.
Hammerhead Sharks
Hammerhead Sharks are relative newcomers to the world of sharks, having first evolved their bizarre hammer-like heads a mere 50 million years ago (give or take a few million). Scientists aren’t exactly sure what benefit their unique heads provide – perhaps greater spacing of their olfactory (scent) sensors helps them locate food with more accuracy and at a greater distance.
What’s freakier than a Hammerhead Shark? How about hundreds of hammerhead sharks – and you just know they’re hungry. Props to the underwater photographer who was able to snap the above shot without shaking the camera. That took guts – and probably a quick change to a clean wetsuit.
Goblin Sharks
Goblin Sharks – an accurate name if there ever was – are rarely seen and that’s not a bad thing for them or us. Living thousands of feet below the surface of the seas, Goblin Sharks have semi-transparent skin that gives them a pinkish hue. The bizarre projection at the top of their heads is believed to house an advanced electroreceptor system to help them home in on prey in the absence of light.
Like many other deep-sea fish, Goblin Sharks employ a “vacuum-cleaner” feeding style that literally sucks prey into their mouths once it gets close enough. It sounds odd and looks even odder. Watch the following video clip of a Goblin Shark in action, looking a lot like the creature from the movie Alien:
Attack of the Goblin Shark, via Bofunk.com, thanks to 12moo13
Thresher Sharks
Sharks are versatile killers from tooth to tail – especially tail, in the case of the Thresher Shark. A 20 ft long Thresher Shark might have half its total length locked up in its tail. Researchers observing Thresher Sharks catch prey found that their typical technique is to swim through schools of fish while whipping their tails, then retracing their paths to snap up any stunned or killed fish.
Thresher Sharks, like most sharks who dwell in the upper reaches of the world’s oceans, have suffered significant drops in population due to overfishing. Sharks are caught not only for their meat, but for their fins – and a Thresher Shark tail would make plenty of bowls of Shark’s Fin Soup.
Frilled Sharks
Frilled Sharks are deepwater fish that are rarely seen at the surface, though they are often caught by bottom trawlers. Long and eel-like, Frilled Sharks are sometimes considered to be “throwbacks” to the early period of shark evolution though their existence today is testament to the success they have found in their particular ecological niche.
Frilled sharks are notorious for their odd dentition. Approximately 300, three-pointed teeth set into 27 rows fill the mouths of Frilled Sharks. Do the math and you’ll find that every Frilled Shark has about 1000 pointy hooks to grab onto its fishy prey. Primitive maybe, deadly definitely.
Spined Pygmy Sharks
Spined Pygmy Sharks are among the smallest members of the shark family, reaching maximum lengths of just 11 inches. Deepwater fish like its close relatives, the Lantern Sharks, the Spined Pygmy Shark exhibits a network of bioluminescent photophores that run along its midsection. It’s thought that the photophores help it blend in with ambient light conditions, thus disguising it from both predators and prey.
Spined Pygmy Sharks were unknown to ichthyologists until 1907, when specimens were caught by members of the U.S. Fish Commission Steamer Albatross during the 1907–1910 Philippine Expedition. Though first found in waters off The Philippines, Spined Pygmy Sharks exist in all the world’s oceans.
White Whale Sharks
Albinos can be found in nearly all animal species and sharks are no different, though at 33 feet long, this albino Whale Shark tends to stand out. Discovered by divers swimming of the coast of the Galapagos Islands in August of 2008, the White Whale Shark was determined to be a young female. Whale Sharks can grow to lengths of 50 to 60 feet and weigh up to 10 tons.
Saw Sharks
Saw Sharks look like Sawfish but they’re not – they’re sharks. Saw Sharks have their gills on each side of the neck like most other sharks while Sawfish gills are positioned beneath their bodies. The lifestyles of Saw Sharks and sawfish are similar, though: swish tooth-studded beak when sea creatures come close, snap up the shredded remnants. In Latin that would be veni, vidi, vici: I came, I saw, I had lunch.
Saw Sharks are not particularly rare, in fact there are seven different species within the two described genera: Sixgill Sawsharks, Longnose Sawsharks, Tropical Sawsharks, Japanese Sawsharks, Shortnose Sawsharks, Eastern Australian Sawsharks, Bahamas Sawsharks, Philippine Sawsharks and (last AND least), Dwarf Sawsharks.
Greenland Sharks
Greenland Sharks may be known as Sleeper Sharks but don’t be fooled – they’re as deadly as their Great White cousins. Indeed, examinations of the stomach contents of dead Greenland Sharks have revealed the remains of Polar Bears and, in one case, and entire caribou, sans antlers. Greenland Sharks have been seen grabbing hold of unwary reindeer who have come too close to the water’s edge. Truly, they’re crocodiles of the sea!
Greenland Sharks can grow up to 21 feet long at achieve weights of 2,200 pounds – over a ton! They can also live for as much as 200 years. You might think that Eskimos and Inuit of the far north would enjoy landing a Greenland Shark and partaking of its meat – not so. Their flesh carries a potent neurotoxin called trimethylamine oxide. The toxin can be rendered harmless, however, by burying the meat and allowing it to rot for a few months, or through several freeze/thaw cycles. Yummy!
Megamouth Sharks
Megamouth Sharks are filter-feeders like Whale Sharks (below) and Basking Sharks. Growing up to 18 feet long and weighing as much as 2.5 tons, Megamouth Sharks are a deepwater species that boasts a ring of light-emitting photophores around its mouth – sort of a deep sea “Eat At Joe’s” sign, though diners quickly become dined upon.
Megamouth Sharks are extremely rare, which may be surprising considering their massive size. The first specimen was described in 1976 and since then, just 51 have been either caught or seen and it has only been filmed three times.
Whorl-tooth Sharks (Helicoprion)
You’ve heard of the Sawshark, now meet Helicoprion, a sort-of “circular saw shark”. Helicoprion is included in this listing of living sharks even though it is extinct, due to its overwhelming bizarreness. It’s thought that Helicoprion’s strange lower jaw slowly revolved over its lifetime, bring new, sharp teeth into position. Alternate theories posit the whorl could be unrolled like a living party favor, snaring and grasping fish as it was reeled in.
One might think that Helicoprion was a mere mutation but the fossil record shows that it was eminently successful, thriving between 280 and 225 million years ago. Like all sharks, Helicoprion’s skeleton was composed mainly of cartilage which does not fossilize easily. It’s bizarre “tooth whorl” is another matter – many have been found in rocks from Idaho, Wyoming and Utah.
Though they may appear bizarre, sharks have a method to their body-mod madness. Hundreds of millions of years of evolution have gone into making them fit perfectly into a huge variety of environmental niches. Sharks are many things but above all, they’re survivors – time will tell if they can survive US.
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