Zhihu Daily
Latest recorded position: #29 on Jul 24, 2026, 8:30 PM CST.
There are not enough retained observations to calculate a rank change.
Why Do Humans Menstruate Monthly While Most Female Animals Do Not?
自然界为啥别的动物雌性没有月经，只有人类女性每个月都要按时流血？
ThreadEast first recorded "Why Do Humans Menstruate Monthly While Most Female Animals Do Not?" on Jul 17, 2026, 9:30 PM CST. It has been observed on Zhihu Daily, with 6 days between the first and latest recorded appearances.
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#29Last observed rank
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