Comment by tialaramex
19 hours ago
Right. It's extremely unlikely that "unable to synthesize Vitamin C" would ever have actively been selected for. But it was also unlikely to be strongly selected against in any version of humans or their near ancestors which have access to basically any common food.
So, randomly this pathway is deleted in our species, but there won't be a satisfying "just so" explanation, it's just blind luck. I happen to think we should fix it, most people either don't care or believe we shouldn't.
Framed in anthropomorphized terms this would look something like the goal of humans as a species is not the synthesis of vitamin C but rather mere survival. Walking a path where we come to depend on external sources is not necessarily at odds with that.
Or more generally: Why did I do that specific thing? No particular reason, it just happened to work. After all, I managed not to fall off the platform for another few seconds. No telling what the future will bring.
As long as we're thinking about anthropomorphization it's amusing to note that vitamin C synthesis can be framed as a species level tragedy of the commons. In that case you are simply advocating that we as a species make the responsible choice not to participate in a race to the bottom!