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amazing facts about sharks !
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Ancient Sharks lived before land vertebrates populated earth and even before than many plants developed on continents. While they were very different from those found today, sharks have been on this planet for long time.
The shark species as we know them have been around for 400 million years. This means that they were here when dinosaurs were around. A record breaking evolutionary creature cannot be anything but amazing, with an anatomy which has been improved over those million years of evolution. Here below in the video there are some of the most amazing facts about sharks. enjoy :) 
No predator, not big cats, ursids, canines, other mammalian carnivores, crocodylids/crocodyliformes, dinosaurs, or even any other animal has lived at an equal time record of 400 million years (~470 million years ago, specifically) as sharks did, unless I'm missing some arthropods or insectiformes/insects, of course.
Even though they're not on my list of favorite animals, I still respect them due to their hardiness and body engineering to preserve their survival. Over the years, we've seen sharks with twisting, monstruous jaws (Helicoprion), sharks with a frequency-sensor/predator scare on their heads (Stethacanthus), sharks who, in a lack of large-bodied animals to feed on, subside on plankton and other nutritional bacteria from both the water and on the ocean floor (Basking Shark), weird-looking sharks (Goblin and Frilled Sharks), sharks who thrive in extreme conditions (Greenland Sharks), sharks who hibernated (Nemihorridus), sharks who were the fastest swimming creature in Earth's history (Cladoselache), sharks who both live on salt and fresh water (Bull Shark and Hybodontiformes), and finally, sharks who gained fame, spanned every ocean in the planet, and became huge (Great White Shark and Megalodon). We normally think of these creatures as man-eating thieves, but when scientists look at their history, they see a whole new perspective: the many failed/successful attempts in which it took sharks to thrive in both size and number in the world's oceans. When I look at the human treeline of evolution, I don't see that much complexity as I do in sharks, big cats and canids do not have that much complexity either (but maybe bears do in forms of dog-like, cat-like, primate-like, and, of course, bear-like creatures), it is just a single line of evolution, we know where modern humans came from, but until today, no scientist knows if the Great White Shark/Megalodon family is a product of a single shark or many sharks. These things I find intriguing about sharks, and instead of visualizing them as enemies, in my opinion, they should be visualized and respected as evolution's hardest work of all time. 
Dating a Greenland Shark. Field Notes by Julius Nielsen. From Natural History magazine Feb. 2017 - on sale now. Far too much for me to hand copy, but according to studies, the details in the magazine, the Greenland shark is probably the longest-living vertebrate animal on Earth today. They probably live ( according to research ) to be more than 250 years old, not reaching sexual maturity until about age 134 years and a length of about 400 cm ( 13 feet ). The only known animal which probably outlives the Greenland shark is the quahog ( Arctica islandica ), a clam. An individual was determined by Paul Butler at Bangor University ( UK ) to be 507 years old.
512-year-old shark discovered in the Arctic could be the oldest living vertebrate
A 500-year-old Greenland shark, which would have reached maturity at around 150 years, sets a new record for being the oldest living vertebrate. Scientists have made a startling discovery where they have found a shark whose age was estimated to be 512 years. Yes, a Greenland shark has been found in the Arctic region and could very well be the oldest living vertebrate on the planet. The research is published in the journal Science. The researchers have measured the creature and estimated that it could be born as early as 1505. Known to live in temperature less than -1 degree Celcius, these creatures can swim as deep as 7,200 feet and weigh more than a tonne. The discovery was detailed in a research study published in the journal Science. Marine biologist Julius Nielsen and his team used a technique to measure the amount of radiocarbon in the eye lenses of Greenland sharks, revealing the possible age of this senior animal. “It definitely tells us that this creature is extraordinary and it should be considered among the absolute oldest animals in the world,” the biologist told.  *This image is copyright of its original author According to reports, the shark measured 18ft in length. It is this length which reportedly can mean the shark can be anywhere between 272 to 512 years old, as this species grows at a rate of 1 cm a year. It is the oldest among the 28 Greenland sharks that are analyzed. These sharks have an estimated lifespan of 400 years and they spend their time swimming around looking for mates. “Fish biologists have tried to determine the age and longevity of Greenland sharks for decades, but without success. Given that this shark is the apex predator (king of the food chain) in Arctic waters, it is almost unbelievable that we didn’t know whether the shark lives for 20 years, or for 1,000 years,” expert Steven Campana from the University of Iceland stated.
It’s not totally clear why Greenland sharks live for so long. Scientists postulate that it may be in their genes, or it could be the fact that they live in relatively cold temperatures and have a slow metabolism.
We might have no exact idea about the reason behind these mysterious creatures for their long lives, but what we can hope is that these vertebrates will boost conservation efforts to protect the species and its habitat. Now that we have found these majestic creatures, it is now up to us to preserve these animals for future generations. “This is the longest living vertebrate on the planet.Together with colleagues in Denmark, Greenland, USA, and China, we are currently sequencing its whole nuclear genome which will help us discover why the Greenland shark not only lives longer than other shark species but other vertebrates,”marine biologist Julius Nielsen, said. When the research scientist was asked how in the world this shark could possibly reach the age of over 500 years old, he guessed that the cold water combined with a slow metabolism would be responsible. He does admit right after, however, that further research is still needed and that this explanation is just a theory. “The answer likely has to do with a very slow metabolism and the cold waters that they inhabit. I’m just the messenger on this. I have no idea.” Read the full article here https://animalchannel.co https://www.majesticanimals.net/512-year...vertebrate 
The World's First Palaeontologist? Shark Teeth Found in City of David Baffle Archaeologists: https://www.haaretz.com/archaeology/.pre...-1.9965614
Ruth Schuster: https://www.haaretz.com/misc/writers/WRITER-1.4968353 Jul. 4, 2021 4:11 PM Lying in the 3,000-year-old filler beneath a home in the Jerusalem site were bullae, pottery fragments – and an inexplicable collection of fossil shark teeth that turned out not to be from meals but from the Cretaceous A fossilized Squalicorax’ tooth from the Jerusalem site. Credit: Omri Lernau Ancient Jerusalem! City of magnetic attraction and religious ecstasy, home of great religions, kings and prophets - and, maybe, the world’s first palaeontologist. An international team of researchers in the city was studying the provenance of fish by the isotope signals of their teeth, as one does. And in the course of their study, they made a stunning discovery. In the garbage of a 2,900-year-old home were normal things such as fish bones, food waste, broken pottery – and 29 shark teeth. It is true that the ancient Jerusalemites in the First Temple Period apparently didn’t adhere religiously to the rules of kashrut. Recent discoveries have found bones from non-kosher fish such as catfish and sharks, though whether they were eaten by early Jews ignorant or defiant of the dietary rules, or somebody else, cannot be certain. The initial assumption was therefore that the shark teeth were food waste dumped nearly 3,000 years ago: https://www.haaretz.com/israel-news/.pre...-1.9231248, https://www.haaretz.com/israel-news/isra...-1.9837609 They were not. Dr. Thomas Tuetken of the Institute of Geosciences at the University of Mainz and colleagues submitted their ground-breaking paper “Strontium and Oxygen Isotope Analyses Reveal Late Cretaceous Shark Teeth in Iron Age Strata in the Southern Levant” for publication in the peer-reviewed Frontiers in Ecology and Evolution. And one of the reviewers pointed out that one of the teeth came from a Late Cretaceous shark that had been extinct for at least 66 million years: https://doi.org/10.3389/fevo.2020.570032 Further investigation showed that all 29 of the shark teeth were fossils, the researchers say. In other words, somebody in ancient Jerusalem, shortly after the legendary reign of King Solomon, collected mineralized shark dentition from the time of the dinosaurs: https://www.haaretz.com/israel-news/who-...-1.9900539 Their findings were presented at the Goldschmidt Conference on geochemistry by the lead researcher, Dr. Tuetken. This research is an international collaboration between the University of Mainz, Haifa University, Israel Oceanographic and Limnological research and Oranim Academic College of Education: https://2021.goldschmidt.info/goldschmid...ingapp.cgi * New type of prehistoric human discovered in Palestine: Homo Nesher Ramla: https://www.haaretz.com/israel-news/MAGA...-1.9935799 * A bird the size of your fist had a head like a T-rex: https://www.haaretz.com/science-and-heal...-1.9936868 * Palestinian archaeologists resolve ages-old evolutionary conundrum: Enter the elephant and the hand axe: https://www.haaretz.com/israel-news/isra...-1.9835193 Where did the shark teeth come from? Not nearby, which makes the paleontological collection even more baffling. Jerusalem’s City of David – found beneath the site formerly known as the Givati parking lot just beyond the walls of the Old City – and the entire area actually sit on a prehistoric seabed. Stroll the hills and in some spots you may find sea urchins, shells and other long-dead life forms from many millions of years ago: https://www.haaretz.com/archaeology/arch...-1.9776035 Dr. Tuetken says that at first he, too, entertained the thesis that the shark teeth had originated in the sedimentary rock strata that comprise the bedrock in and around Jerusalem and beneath the City of David. “However, it seems that no fossil shark teeth finds are reported from the Jerusalem/City of David area. Furthermore, the Cretaceous sediments have a slightly different age from the fossil shark teeth. That does not fit,” he explains to Haaretz. Similar finds of late Cretaceous shark teeth were made in Maresha and Miqne (Tel Ekron), in ancient Judea, the team adds, and their rationale is as baffling as this one: https://www.haaretz.com/archaeology/.pre...-1.5337806 Artist’s impression of a Squalicorax shark. Credit: Dimitri Bogdanov (2008) The teeth may have come from the Negev, where similar fossils have been found, Tuetken suggests. “These fossils are not in their original setting, so they have been moved. They were probably valuable to someone; we just don’t know why, or why similar items have been found in more than one place in Israel,” he says. We add that the teeth were subsequently identified as coming from multiple extinct shark species, including from Squalicorax, a fish that grew up to 5 meters (16.4 feet) in length and apparently only lived in the Late Cretaceous – the same period as the late dinosaurs. It was a reference point in dating these fossils, the researchers elaborate. A Squalicorax pristodontus’ tooth in Erfoud (Arfoud), Meknès-Tafilalet Region, Morocco. Credit: Parent Géry (27th of March, 2012) A strange pool However prized the fossil fangs were to whoever collected them, they were found in the detritus, including household garbage, that was used to fill in a cavity hewn in the rock, on top of which a large Iron-Age house was built. Asked how they know it was a home, Tuetken reveals another oddity. There was a “pool” cut into the bedrock, but that was a misnomer, he explains: “Apparently, it never served as a pool, a water reservoir, as the bottom of this “pool” is at a higher level than the spring nearby. This large cavity was cut into the rock, about 10 meters (32.8 feet) deep, and its original purpose is still unclear.” The rock-cut pool site was excavated by Professor Ronny Reich from Haifa University. Come the late 9th century B.C.E. or early 8th century, this pool, or cavity, was filled up with two meters of stuff and soil. “This fill contained different items including 10,600 remains of fish, hundreds of broken bullae (tin seals) and more. The fill was considered to consist of garbage collected nearby,” Tuetken says. Then in the mid-8th century B.C.E., a house was built on the filled “pool.” The pottery in the filling correlates with Iron Age IIA, which dates it to 1,000-925 B.C.E. “The structure built on the pool was filled after 925 B.C.E. with trash from a previous period and was part of a residential quarter, located on the lower section of the eastern slope of the City of David,” he tells Haaretz. And now we may speculate why somebody in First Temple Jerusalem would collect fossil shark teeth. Tuetken says he isn’t aware of any other fossil collections in ancient Jerusalem. There are no indications that the teeth were used in jewellery – for instance, there are no drill marks – and no indications they were used as tools, which would have worn them down. Could they have been seen as a rare, valuable oddity? Perhaps a sort of currency: You did an extraordinary job for the king, here, have a stone shark tooth? Tuetken doesn’t think so, but does point out how rare they are: 29 out of 10,000 fish remains are shark teeth, and they don’t appear together. One has to sieve through the sediment to find them. He has another theory, though: “We know that there is a market for shark’s teeth even today, so it may be that there was an Iron Age trend for collecting such items. This was a period of riches in the Judean Court,” he points out. However, Tuetken begs caution: “It’s too easy to put two and two together to make five. We’ll probably never really be sure.” We add that a shark tooth is a thing to marvel at; maybe somebody 3,000 years ago in ancient Jerusalem was captivated by the bewildering mineralized versions. They may have seemed somehow miraculous, we say cautiously, and maybe thusly the first palaeontologist was born. Why and how the precious, rare collection was then discarded remains fodder for couple’s counselling. 
Scientists discover three glow-in-the-dark sharks
 *This image is copyright of its original author
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