My guess is we have a perception of how fast things relative to their size should be able to move. Someone above gave the example of Godzilla. If you were to resize a human to that size, we’d go a lot faster than Godzilla would. And hence, for its size, Godzilla is probably slow.
For Ants, they’re pretty fast compared to their size. If we were that size, they’d leave us behind to be eaten.
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