Researchers are catching and tagging sharks to learn more about their population. A young sand tiger shark was recently caught and tissue samples were taken. The shark's skin was found to be so thick and rugged that it snapped a surgical-grade scalpel.

The researchers are attaching small data collection devices to the sharks before releasing them. This effort aims to shed more light on the shark population. Further details about the research and its goals are available from the source, including comments from shark researcher Greg Metzger about the resilience of sharks.