Dr. Adam Summers from University of Washington uses clearing and staining in order to make the fish transparent and to let us see the beauty of their bones.
The process he follows is not a new one, but the result is incredible. He first hardens the fish, then colors the cartilages and bones and then uses trypsin to eat up all the flesh and then leave only a transparent skin made out of colagen.
After this he bathes the fish in glycerine and voila, here is your work of art, Nature. Nice one, Science Friday.