My point was that if getting a cold made a significant difference in the likelihood of some cancer then you may be substantially undercounting the risk of that cancer to children in the counterfactual where there is no susceptibility to colds.
(To be clear, I don't think the parent's speculation is likely accurate. I do think it's interesting.)
Do kids (and people in general) get substantially less colds in warmer climates? Because then we can check cancer rates there. (And spend a lot of effort on controlling for other differences.)
I wonder if anyone did this kind of data fishing.
Yeah, there's some tension between risk of being seen as condescending and making sure everything is sufficiently clear. In a low-stakes context like this (and outside of clarifications or responses to ELI5 requests) I try not to fill in all the gaps - when it goes well it leaves us all feeling a little smarter and when it goes wrong it occasionally leads somewhere interesting. The increased risk of misinterpretation was made even worse here by the priming of several other people making the point I wasn't.
Flu are truly scary causing deaths throughout childhood with increased survival around two years and then again around five years. My youngest turns five this month. Before she was two she was hospitalized with croup and she has had a rougher ride with illness than my other kids along the way too.
Other special populations of children include those with AIDS, CF, DM, and any other immunocompromising condition or respiratory anomaly.
Having addressed the special populations that are implicitly not the targets of broad comments:
Typical children tolerate colds just fine. It’s not the flu.
(Croup is also not a cold.)
I appreciate you being complete here, though your opening also reads like you are doubling down on your previous response.
Your comment about croup is also bizarre, as the paragraph I included mention of it in is not about colds. Context matters.
Evolution started without any of those.
Your reply fails to acknowledge it.
Your comment seems, by implication, to make a similar mistake: it doesn't matter much how long we were in a different situation - what matters is whether we've had enough of a chance to adapt to the new one. It doesn't take (k)X years to "undo" adaptations that took X years to find.
And yes, the 100 years you give are clearly not enough generations to do much adapting. Some of the items mentioned in the earlier comment (clothes, fire, shelter) are things humans have had for substantially longer than 100 years. But I don't know enough about the relevant time scales for anything to be clear to me about how much we've probably adapted to having them, which is why I didn't speak to that.
My view is that the past century or so may be an increased period of both driftband (through geographic contact) remixing, possibly to be followed by a selection process, whether by civilisation collapse, singularity, or other mechanisms.
In particular, it seems that the dramatic reductions of, e.g., early childhood mortality, represent the lifting of an immense amount of selection. To what end becomes an interesting quesstion.
Similarly how we have the surplus resources to keep people alive and well (and thus productive) with seriously adaptive-maladaptive trait groups, eg. Stephen Hawking and other famous physicists of the 20th century. https://slatestarcodex.com/2017/05/26/the-atomic-bomb-consid...