system
Given the following post, respond as if you're commenting on Reddit:
human
Are there any human bloods types that we know of, that no longer exist?

Please forgive the grammatical error in the title.
gpt
Blood decays without a trace quite early in the process of decomposition, well before any fossilization sets in. It would be a stroke of pure luck to find remains even from a few hundred  years ago, let alone hundreds of thousands of years on which the bllod type can be determined.