25-Year-Old Shark Bite Mystery Solved by DNA from Tooth in Florida’s Man’s Foot

Jeff Weakley was shocked to find a piece of a tooth from a shark that bit him when he was on his surfboard surfing off Flagler Beach in 1994 when he tweezed open a blister-like bulge on his foot. Also, he was amazed that a DNA test of the tooth, which scientists at the Florida Museum of Natural History conducted, would reveal the kind of shark that had caught his foot nearly a quarter-century ago; a blacktip. In his plan, Weakley wanted to turn the small sliver of a tooth into a pendant when he read about how researchers in the Florida Program for Shark Research discovered the shark species responsible for a bite of New York by analyzing DNA from a tooth retrieved from the leg of the victim.

Then, Weakley decided to offer the tooth to science.

The editor of Florida-Sportsman magazine, Weakley said that he was quite excited to determine the identity of the shark because he's always been curious. Also, he was a bit hesitant to send the tooth in because, for a moment, he thought the scientists would come back and inform him he's been bitten by a mackerel or a houndfish. But his bite was the real deal, caused by Carcharhinus limbatus, a shark species commonly involved in bites in Florida.

Weakley was not surprised by the result since he had always suspected a blacktip. However, the director of the shark research program, Gavin Naylor, was shocked because the fact that any viable DNA was left in the tooth fragment to analyze, after 24 years in Weakley's foot where it would have been attacked by his immune system.

Naylor said that he had put their odds of success at slim to none. Lei Yang, his laboratory manager, shared his doubts and he noted that it was weird to test the tooth, but was also intrigued to try. It was a mystery waiting for them to uncover.

Yang said further that unidentified species are the cause of about 70 percent of shark bites and more precise data on which species are involved could improve bite mitigation strategies. Also, Yang understood the personal curiosity of Weakley. He explained that if he were bitten by a shark, he would want to know what it was.

According to Weakley, he explained that he had been lucky to have not been bitten by a dog, but would regard that interaction he has with that shark as being no different or more destructive than a dog bite.