The title "Populator" is inspired by the 2000 book "Fatalis", written by Jeff Rovin. Both fatalis and populator are species names to the genus Smilodon, the famous sabre-toothed cat.
Sources for this story come from publications by Karl Shuker, including of the "Mutant Jaguar" of 1975 Paraguay and the sightings of "water tigers" in South America.