Well, it's Shark Week, and apparently the sharks aren't happy. According to a Google engineer, the company has to wrap its undersea fiber optics cable in kevlar to protect them against shark attacks.
See for yourself:
It's not that sharks are pissed about their portrayal in the media and want to fight back. Theories as to why they do this range from sharks being attracted by the electro-magnetic fields that are leaking from the cables, which they might be able to detect, or just good old curiosity, making them nibble on random things that they find.
Either way, unprotected cables can easily be damaged by shark teeth, and doing repairs at the bottom of the sea isn't exactly easy...
While humans are millions of times more dangerous for sharks than sharks are for humans, they still try to eat human things from time to time, and not just undersea cables. Here's a great white trying to eat a remote-controlled robot:
In recent years, an unusual spate of deadly shark attacks has gripped Australia, resulting in five deaths in ten months. At the same time, great white sharks have begun appearing in growing numbers off the beaches of Cape Cod, Massachusetts, not far from the waters where Steven Spielberg filmed the ultimate shark fright film, Jaws. What's behind the mysterious arrival of this apex predator in an area where they've rarely been seen for hundreds of years? Are deadly encounters with tourists inevitable? To separate fact from fear, NOVA teams up with leading shark experts in Australia and the United States to discover the science behind the great white's hunting instincts. Do sharks ever target humans, or is each attack a tragic case of mistaken identity? And can a deeper understanding of shark senses lead scientists to design effective deterrents and help prevent future attacks?
While on a quest to create effective shark repellents, marine biologist Patrick Rice stumbled upon an unexpected type of shark “kryptonite.” He found that rare earth elements, like samarium, create an electric current when they are submerged in salt water next to a shark fin. Fishing hooks made out of rare earth elements could repel sharks while still luring other types of fish.