During his famous 5 year-long expedition to Latin America (1799-1804), Alexander von Humboldt collected,  together with his naturalist partner, Aimé Bonpland, around 60,000 plant specimens and an unknown number of animal specimens that we can safely assume to be in the thousands. Some of these specimens were being shown and described to the scientific world for the first time, including the peculiar yellow-tailed woolly monkey. However, the monkey specimens weren’t caught by Humboldt or Bonpland. They were the flat skins…