Csiro scientists: Humans have a “natural” lifespan of around 38 years

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6 points·lysp··3 comments

This quote in particular didn't excite me: "We removed humans (Homo sapiens) from the data set as they were listed with a maximum lifespan of 120 years, which does not reflect the variability and the true global average lifespan (60.9–86.3 years)."

Editing out data like that seems like fitting the data to expectations rather than letting it lead you based on its own trends. It doesn't do much good for the headline either.

I'm fairly sure that modern humans lifespans were shortened due to infant mortality rather than some aspect of the genetic clock. Its hard to keep average lifespan high when most of your children die due to disease and DNA doesn't have that many opinions relating to that and its view of maximum lifespan. If it did have opinions (unlikely) it would be simple enough: "lets find some individuals with some resistance to mix and make more of them". But requiring that DNA fit a narrative seems unnecessary.

1: They threw out the 120 year number since it was reported differently for humans than it was the rest of the animals in the data set. Those numbers would have been the average of the 10% of the eldest members in the study, while 120 is the maximum reportedly seen in humans.

2: You're thinking of life expectancy instead of lifespan for the last part.

Report: https://www.nature.com/articles/s41598-019-54447-w

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