That marmosets can learn from other marmosets isn't all that surprising. Slightly more impressive is that they can learn from unfamiliar marmosets, who they haven't met before. But what's really amazing is they can learn from instructional videos.
New World Monkeys are the strangest-looking primates on Earth — and they all look nothing like each other, from the bald-headed, demon-like Uakari to the lion-maned golden marmoset to the massively mustachioed emperor tamarin up top. What's behind this insane variety?