It makes the hurdle less likely to be before the fish stage, so more likely to be after the fish stage. While the biggest increase in probability is immediately after the fish stage, all subsequent stages are a more likely culprit now (especially as we could simply have missed fossils/their not have been formed for the post-fish stages).
So finding evidence of life that went extinct at any stage whatsoever should make us revise our beliefs about the Great Filter in the same direction? Doesn't this violate conservation of expected evidence?
We've had these for a year, I'm sure we all know what to do by now.
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