Neanderthals were worriers and worrying is and always has been associated with high native intelligence. It is a cluster of genes and they don't come customized as individual plug-in modules - if you got the DRM and DRD clusters then you got the whole shebang, not just the ones that improve the quality of neurotransmitters in the brain. This is why I say the two species are mixed together like oil and water in the gene pool ... in other words, never really mixed at all.
I challenge the readers of this blog to find me one person with a clinical IQ over 160 who has not constructed an underground shelter. I will bet you that you can look all you want and you won't find one.
Linus Pauling had a vault. Robert Heinlein had a vault. Freeman Dyson had a vault.
All geniuses build vaults or desire to build them as soon as possible. You're in good company. All the genes involved in these things come in a package, along with sleep disorders, depression, alienation, hyperfocus, ADHD, compulsive hoarding ... it's all part of the same group because it is all Neanderthal.
If you're so dumb you never worry, wouldn't you disparage worrying as a character flaw? It only makes sense. Oprah Winfrey and her obsession with "negative" emotions couldn't build a civilization if she had a million years and all the money on earth. She is a static constant, which is a very diplomatic and tactful way of saying she is not really human at all compared to the sort of person who takes pride in worrying about the future and projecting him or herself into it in order to be ready for it when it gets here.
At least a half a million years they survived with these traits, in conditions that would have eliminated Homo Sapiens in a day. The most unimaginable catastrophic events rolled off the Neanderthal's back like water off a duck. He was so paranoid he always had a backup for his backup ... from all that worrying. It would be fair to say the only thing that ever blindsided him was Homo Sapiens the species, seemingly designed to exterminate the ultimate survivor above all other species.