A team of divers have captured what's thought to be the first photo ever taken of a live birth of an oceanic shark.
Photographer Attila Kaszo took the picture, close to an underwater mountain in the Philippines, but didn't realise at the time that it showed the birth.
"It was one of the most exciting moments in my career" said Dr Simon Oliver from the University of Chester, who was involved in the research.
Why the birth is important
The Thresher shark is a vulnerable species. That means it could become extinct unless numbers increase.
Dr Simon Thorrold, a senior scientist from Woods Hole Oceanographic Institution in Massachusetts, US, says the picture is "amazing".