Comment by czinck

I asked Claude Opus 4.6, Sonnet 4.6, Gemini 3 Thinking, and Gemini 3 Fast "Tell me about the Siberian marmoset" exactly and all 4 said it doesn't exist, with Gemini Thinking suggesting that I'm thinking of the Siberian marmot or Siberian chipmunk (both real animals).

https://en.wikipedia.org/wiki/Tarbagan_marmot (also known as Siberian marmot)

https://en.wikipedia.org/wiki/Siberian_chipmunk