Various scenarios that put more or less every folks in space for extended periods of time in microgravity in the future have been proposed, mostly based on space tourism but there could be colonization scenarios as well. Yes artificial gravity is also proposed in some cases, but for the purpose of this question let's stick to microgravity.
Question: What animals would be best suited as pets or comfort animals for extended periods of spaceflight in microgravity?
From How would a mousetrap for use in space work?
Screenshots from Mice aboard the International Space Station
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