Treehugger reports on the work of marine scientists at Brazil’s Guaruja Aquarium, who have added a plastic window onto a shark egg so they can watch the fish develop.

In the photo above you can see the fetal bamboo shark attached to a large yolk sac. The video below gives a better view.
After noting that the unborn shark was unaffected by the window on its neonatal world, researchers removed the entire animal from its purse and allowed it to grow inside a perspex container. The work will help shed more light on how young sharks develop, an understanding of which is crucial to the conservation of threatened shark species.