I want to know the answer to the following question:
What caused Darwin to change his mind about the unbridgeable gap between animals and humans?
All the background I'm provided with is that "The three Fuegian missionaries the expedition returned to Tierra del Fuego were friendly and civilised, yet to Darwin their relatives on the island seemed "miserable, degraded savages", and he no longer saw an unbridgeable gap between humans and animals.". Is that enough to answer the question?