Ever wonder why sharks have so many differently shaped teeth or why they keep regrowing throughout their lives? Dr. David ...

This is a photograph of shortfin mako shark scales which each measure about 0.2 millimeters in length. The front row of scales has been manually bristled to their maximum angle of about 50 degrees ...

Scientists have discovered that the long-extinct megalodon, also known as the megatooth shark, had a body temperature 7 degrees Celsius warmer than the surrounding seawater. This information might ...

This story appears in the August 2017 issue of National Geographic magazine. Zane Grey made his name writing adventure novels about the American West, but his real love wasn’t gunslinging or ...