So you learned everything you know about sharks from a scary movie? – Harvard Gazette

“They’ve had a tough time in the last few years,” mentioned George Lauder, the Henry Bryant Bigelow Professor of Ichthyology at Harvard. Sharks face a warming ocean, ocean acidification, lack of prey, and plenty of extra dire challenges, Lauder mentioned in his introductory remarks.

“This is bad news, but it’s not a lost cause,” Shiffman mentioned. “We can help sharks.”

But why ought to we? The best purpose, by far, is that sharks are crucial cogs in ocean ecosystems, Shiffman mentioned. Ocean meals webs are advanced and susceptible; eradicating a predator can have disproportionate impacts, doubtlessly inflicting the entire system to unravel. Sharks even have uncommon biology and skills. Their skeletons are constructed from cartilage, not bone, which can assist them heal quicker. (Try to bend your forearm, Shiffman mentioned to his viewers. Then crinkle your ears. That’s the distinction between bone and cartilage).

Sharks’ imaginative and prescient and sense of scent are higher than people’, they usually have a way we lack: Because sharks can detect electromagnetic fields, they will spot prey hidden underneath the sand by sensing the electrical energy of their beating hearts. The hammerhead shark’s lengthy, flat head is sort of a metallic detector, designed to scan the seabed for heartbeats as an alternative of misplaced cash. Sharks additionally use the Earth’s magnetic subject to navigate from a favourite seaside to a selected island with out getting misplaced at sea.

In addition, many species possess different helpful traits. Some have biofluorescent mouths, which lure prey to swim proper in. (“That is snack time goals,” Shiffman mentioned.) Some glow at the hours of darkness. The goblin shark can hyperextend its jaw to raised gobble up prey. The thresher shark makes use of its tail like a whip, making a shock wave that stuns its meals. And the Greenland shark eats polar bears and might reside for greater than 400 years.

“You often think of sharks as being fast and powerful,” mentioned Shiffman. But his favourite shark, the sandbar shark, is gradual and lazy. Many misconceptions, he mentioned, may be tied to Steven Spielberg’s “Jaws,” which portrayed sharks as evil monsters that hunt people. “Spielberg has a lot to answer for,” Shiffman mentioned. “Shark attacks are unbelievably rare and unlikely.” About 38 % of reported shark assaults in Australia are false, he mentioned.

Shiffman wrote his e book to dispel these misconceptions and supply sensible methods individuals can assist save sharks. Some who need to assist, he mentioned, are doing extra hurt than good. Groups of individuals Shiffman calls “macho cowboy idiot scuba divers” take images of themselves driving, hugging, and kissing sharks on the face. “Don’t do that,” Shiffman mentioned.

During the question-and-answer portion of the speak, viewers as younger as 4 years previous requested why some sharks are bubble-gum pink (the reply: they reside the place gentle can’t attain, in order that hue makes them near-invisible) and whether or not shark-deterrence applied sciences really work. “The most charitable thing I can say is that some of them work sometimes under certain conditions,” Shiffman mentioned.

One viewers member requested whether or not Shiffman took a dip off Cape Cod, the place he’d given a e book speak the week prior. Shiffman responded with an anecdote: He was standing on a seaside with a colleague who pointed to a spot the place the ocean turned from gentle brown to black, the mark of a pointy drop-off. See that spot? His colleague requested. We have a sensor there that detected an grownup nice white shark on the market 99 % of final week.

“So, yeah,” Shiffman mentioned. “I didn’t go swimming.”

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