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Extreme Sharks Breakers 145 RECORD 144 Extreme Sharks BREAKERS 145 Biggest, smallest, Sometimes, a single shark in a species grows bigger, stays smaller, or swims faster than the rest of the fastest, strongest—for members of its species. Here are some extremes and some average. sharks, it’s just their nature to grow and move as quickly as they can. TEN BIGGEST SHARKS IN THE WORLD This list shows the maximum and average sizes for each of the ten biggest sharks recorded by scientists. The list changes all the time, as bigger sharks are observed or caught and as more data is collected. There may be bigger sharks out there, but these are very big sharks! 1. Whale1. Whale shark shark Maximum:Maximum: 65.6 65.6 feet; feet; Average: Average: 23 feet23 feet 2. Basking shark Maximum: 29.5 feet; Average: 21.7feet 3. Pacific sleeper shark Maximum: 23 feet; Average: 13.1 feet 4. Greenland shark TEN SMALLEST Maximum: 22 feet; Average: 10.5 feet SHARKS BIGGEST TAIL DISCOVERED 5. Great white shark Common thresher. Up to 5. Great white shark 52 percent of body size, 12 1. Dwarf lanternshark Maximum:Maximum: 20.2 20.2 feet; feet; Average:14.2 Average:14.2 feet feet feet long, 800 pounds. 6.7 inches 2. Pale catshark 6. Common thresher shark BIGGEST TEETH 8.3 inches Maximum: 20.1 feet; Average: 11.2 feet Great white shark. 3. Smalleye pygmy shark 7. Great hammerhead Up to 2 inches long. 8.7 inches Maximum: 19 feet; Average: 8.6 feet BIGGEST MOUTH 4. Panamaghostcatshark 8. Megamouth shark Whale shark. 9.1 inches Maximum: 18 feet; Average: 14.8 feet Up to 15 feet wide. 5. Green lanternshark 9.1 inches 9. Tiger shark THICKEST SKIN 6. Shorttail lanternshark 9. Tiger shark Whale shark. Maximum: 18 feet; Average: 9.2 feet 9.4 inches Maximum: 18 feet; Average: 9.2 feet Up to 3½ inches thick. 7. African lanternshark 10. Goblin shark BIGGEST EYES 9.4 inches Maximum: 16.4 feet; Average: 9.8 feet Bigeye thresher shark. Up to 4 percent of body 8. Spined pygmy shark length, 7 inches high. Biggest by proportion of any 9.8 inches vertebrate other than birds. If a 5-foot-tall person had 9. Atlantic ghost catshark eyes this big, they would be 2½ inches wide. 9.8 inches 10. Broadnose catshark 10.2 inches RECORD 146 Performance Records BREAKERS 147 If there were a shark Olympics, these sharks would be gold medalists. They can’t be judged the same way swimmers and ice skaters are, but researchers have ingenious machines and experiments to measure a shark’s performance. LIFE CYCLE RECORDS Researchers gather as much data about shark lifespans and birth records as they can—but it’s difficult to get exact numbers because sharks don’t fill out questionnaires. FASTEST The salmon shark was clocked MOST SHARK PUPS by the U.S. Navy at 55 miles per (BABIES) IN A SINGLE LIttER hour. Previously, the shortfin Live birth: blue shark. 135 pups.; mako, which had been clocked From eggs stored in a female shark’s body: at 44 miles per hour, was Whale shark. 300 eggs in a whale shark considered the fastest. captured in 1996. SMALLEST WHALE SHARK PUP 15 inches long—but shark pups grow to more than 40 feet by adulthood. SMALLEST PUP The pups of the dwarf lanternshark are under 2.5 inches long. SHORTEST PREGNANCY Bonnetheads give birth to live pups that hatch from eggs stored in the mother’s belly after five DEEPEST-DIVING months of pregnancy. A Portuguese dogfish was found 12,000 feet below the surface during a study of LONGEST PREGNANCY deep-sea fish. These sharks spend most The spiny dogfish is pregnant for about two of their time below 1,200 feet, but the years. Right now, that is the longest confirmed 12,000-foot-deep waters are probably shark pregnancy on record. It is also one of not where it spends all its time. the longest pregnancies of any animal—only the black alpine salamander’s is longer, at three years in cold climates. But scientists are investigating evidence that other sharks, including the frilled sharks, may be pregnant for three and a half years or more. For now, the spiny dogfish holds the record for longest BEST pregnancy among sharks. HEARING LONGEST-LIVED SHARK The silky shark has Scientists think the Greenland shark can live responded to low- LONGEST MIGRATION more than 200 years, based on its rate of growth, frequency sounds A great white shark named Nicole migrated but they haven’t yet found a way to prove this. from ¼ mile away. from Africa to Australia and back—a journey of over 12,000 miles—in nine months. Her epic migration was recorded with a tracking device. .
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