In a study starting in 2011 Paolo Guidetti, a biologist at the University of Salento and Fiorenza Micheli, a biologist at Stanford University made a study of how often and in what context a fish called a grouper appeared in Roman mosaics to see if they could determine how prevelant they were. They looked at 73 Etruscan, Greek and Roman mosaics from between the first and fifth centuries that showed fish or fishing scenes. Of those, 23 had groupers. They were able to show that these fish were much more common, much larger and more accesible to catch than now. Mosaics show men fishing for groupers with harpoons at the water's surface. Today, this would be unheard of.