The most notorious and feared prehistoric shark
Megalodon (Carcharocles megalodon) is an extinct species of shark that lived approximately 23 to 2.6 million years ago (mya), during the Early Miocene to the end of the Pliocene. Its name meand “big-tooth”. It was formerly thought to belong to the family Lamnidae, making it closely related to the Great White shark (Carcharodon carcharias). However, most researchers now believe that it belongs to the extinct family Otodontidae. Megalodon is one shark that has been a part of our imaginations and childhood wonder.
Family: †Otodontidae (previously classified under Lamnidae)
Genus: †Carcharocles (or possibly Otodus)
Family– †Otodontidae (previously classified under Lamnidae)
Common Name– Big Tooth
Genus– †Carcharocles (or possibly Otodus)
Status: EXTINCT. Megalodon preferred warmer waters. Scientists believed that oceanic cooling associated with the onset of the ice ages, coupled with the lowering of sea levels and resulting loss of suitable nursery areas, may have also contributed to the decline of Megalodon. A primary food source, baleen whales, may have also contributed. When baleen whales shifted in location, the loss of the food source may have been significant. The extinction of Megalodon appeared to affect other animals; for example, the size of baleen whales increased significantly after the shark had disappeared.
An analysis of the distribution of Megalodon over time suggests that temperature change did not play a direct role in its extinction.
The earliest Megalodon remains were reported from the Late Oligocene dated to around 28 million years ago (mya), competing figures still exist as to when it evolved, such as 16 mya and 23 mya. It is believed that Megalodon became extinct around the end of the Pliocene, probably about 2.6 mya; reported Pleistocene megalodon teeth, younger than 2.6 million years old, are considered to be unreliable claims. Current research, and fossil findings suggest that they may have been extinct 3.5 million years, instead of 2.5 million years ago.
Being that Megalodon preyed upon whales primarily, only when their main food supply began to diminish, did they eat smaller prey such as seals and turtles. Megalodon had to eat around 2,500 pounds of food in a given day. With this drastic dietarily change, Megalodon was faced with competing directly with another species of shark, the Great White shark. Some scientists suggest this is a direct contribution to its extinction; the Great White shark has a much more efficient design and adaptation for catching such prey as seals.
Average Size and Length: Megalodon has a maximum recorded length of 59 feet, with an average of 34 feet.
Average Weight: Based on fossilized teeth, Megalodon was believed to weigh on average 60 tons, but some research suggests between 60 and 100 tons.
Current Rare Mythical Sightings: In general, the human population would like to believe that Megalodon still exists. When I was a little girl at the age of 6, I decided that Megalodon lives in the deepest darkest depths of the Marianas Trench.
HMS Challenger in 1873 made reports of supposedly fresh Megalodon teeth. It turns out those were incorrectly dated to be around 11,000 to 24,000 years old, are probably teeth that were well-preserved by a thick mineral-crust precipitate of manganese dioxide, and so had a lower decomposition rate and retained a white color during fossilization. The claims that Megalodon could remain elusive in the depths are unlikely because Megalodon lived in warm coastal waters and probably could not survive in the cold and nutrient-poor deep-sea environment.
The Discovery Channel and some sister channels have produced and aired many series claiming new evidence, that turned out to be fiction. Just like myself, I would say everyone loves a good story, especially one involving an extinct, prehistoric shark. I certainly didn’t miss The Meg movie summer 2018. My childhood fantasies are fulfilled!
Teeth and Jaw: One interpretation suggests that the jaws are blunter and wider than that of a Great White shark. It is possible that the jaws could have spanned over 6.6 feet across. The jaws contained over 250 teeth, spanning 5 rows. Research also suggests that Megalodon could have been able to open its mouth to a 75-degree angle.
Gordon Hubbell from Gainesville, Florida, possesses an upper anterior megalodon tooth whose maximum height is 7.25 inches, which is one of the largest known tooth specimens from Megalodon. A 9 by 11- foot Megalodon jaw reconstruction developed by fossil hunter Vito Bertucci contains a tooth whose maximum height is reportedly over 7 inches.
Teeth are triangular in shape with fine serrations, a lack of lateral denticles, and a visible V-shaped neck. The tooth met the jaw at a steep angle, similar to the great white shark. The tooth was anchored by connective tissue fibers, and the roughness of the base may have added to mechanical strength. The lingual side of the tooth, the part facing the tongue, was convex; and the labial side, the other side of the tooth, was slightly convex or flat. The anterior teeth were almost perpendicular to the jaw and symmetrical, whereas the posterior teeth were slanted and asymmetrical. Fossil megalodon teeth can vary in color from off-white to dark browns and greys, and some fossil teeth may have been redeposited into a younger stratum.
Dr. S. Wroe and his team conducted an experiment in 2008 that basically resulted in an estimated bite force of Megalodon to be between 110,000 and 180,000 newtons.
Head: Scientists believe that Megalodon may have had a broader more dome-shaped head and a shorter more-blunt snout then that of a Great White shark. Again, this is based on fossilized Megalodon teeth. These interpretations are based more on if Megalodon is in Otodus instead of Carcharocles Genus.
It may have had a pig-eyed appearance, in that it had small, deep-set eyes.
Tail: Thought to be crescent shaped.
Demographic, Distribution, Habitat, Environment and Range: Megalodon had a cosmopolitan distribution; its fossils have been excavated from many parts of the world, including Europe, Africa, the Americas, and Australia. Locally, two of the best places to find Megalodon teeth is “The Graveyard” Venice Beach, Florida, and South Carolina mining in the mountains. It most commonly occurred in subtropical to temperate latitudes. It has been found at latitudes up to 55° N; its inferred tolerated temperature range was 34–75 °F. It arguably had the capacity to endure such low temperatures due to mesothermy, the physiological capability of large sharks to conserve metabolic heat by maintaining a higher body temperature than the surrounding water.
Megalodon inhabited a wide range of marine environments (shallow coastal waters, areas of coastal upwelling, swampy coastal lagoons, sandy littorals, and offshore deep-water environments), and exhibited a transient lifestyle. Adult Megalodon were not abundant in shallow water environments, and mostly inhabited offshore areas. Megalodon may have moved between coastal and oceanic waters, particularly in different stages of its life-cycle. Megalodon teeth have been excavated from regions far away from continental lands, such as the Marianas Trench in the Pacific Ocean.
Diet: Scientists believed that Megalodon targeted large prey, such as whales, seals, and giant turtles. Juveniles inhabited warm coastal waters where they would feed on fish and small whales. Megalodon probably used its strong jaws to break through the chest cavity and puncture the heart and lungs of its prey. One of its favorite prey items was Baleen whales.
Megalodon faced a highly competitive environment. Its position at the top of the food chain probably had a significant impact on the structuring of marine communities.
Megalodon bite marks on whale fossils suggests that it employed different hunting strategies against large prey, such as biting through bone. In other research and prey fossils found, Megalodon rammed its prey with great force from below before killing it and eating it.
During the Pliocene era, larger and more advanced cetaceans became apparent. Megalodon apparently further refined its hunting strategies to cope with these large whales. Numerous fossilized flipper bones and caudal vertebrae of large whales from the Pliocene have been found with Megalodon bite marks, which suggests that megalodon would immobilize a large whale by ripping apart or biting off its fins before killing and feeding on it.
Ram-Suction Index: Research suggests ram
Aesthetic Identification: Based on fossilized teeth, the most agreed upon scenario is that Megalodon had to be extremely large to support the massive teeth and jaw. Paleontologists and other scientists believe that Megalodon would have had to have been stout, and more strongly developed with a blocky skull. Over the last century, some vertebrae have been found to support this.
One theory is that the anal fin and second dorsal fin would have been small, and there would have been a caudal keel present on either side of the tail fin (on the caudal peduncle). This build is common in other large aquatic animals, such as whales, tuna, and other sharks, in order to reduce drag while swimming. Considering its massive weight, it probably had extra-long pectoral fins.
Biology and Reproduction: Scientists believe that Megalodon’s large size may have been due to climatic factors and the abundance of large prey items, and it may have also been influenced by the evolution of regional endothermy (mesothermy) which would have increased its metabolic rate and swimming speed.
Fossil evidence suggests that the preferred nursery sites of Megalodon were warm-water coastal environments, where threats were minor and a large abundance of food.
Nursery sites were identified in the Gatún Formation of Panama, the Calvert Formation of Maryland, Banco de Concepción in the Canary Islands, and the Bone Valley Formation of Florida. Given that all existing lamniform sharks give birth to live young, this is believed to have been true of Megalodon as well. Infant megalodons were around 11 ft at their smallest, and the pups were vulnerable to predation by other shark species, such as the Great Hammerhead shark and the Snaggletooth shark.
An exceptional case in the fossil record suggests that juvenile megalodon may have occasionally attacked much larger balaenopterid whales.
Behavioral Traits, Sensing and Intelligence: Not much is known about the social behaviors of Megalodon, however some scientists believe they could have had flexible hunting behaviors, and adaptations. Some research suggested they could hunt in packs.
Megalodon did evolve intelligently and adapt different hunting strategies with different prey.
Speed: A 2015 study linking shark size and typical swimming speed estimated that megalodon would have typically swum at 11 mph, given that its body mass was typically 48 metric tons (53 short tons), which is consistent with other aquatic creatures of its size, such as the fin whale which typically cruises at speeds of 9.0 to 13.4 mph (Jacoby, D. M. P.; Siriwat, P.; Freeman, R.; Carbone, C. (2015).