The original title (which makes a lot more sense than the abbreviated one used for the submission):
> The Colorado River disappeared from the geological record for 5 million years: Scientists now know where it went
Removing the word "record" actually make the HN-submitted title make more sense. Wrapping "disappeared" in quotes actually conveys more or less the same intent.
The HN title limit and automatic title editing is really the stupidest thing I've ever seen, especially for a site that claims to not want editorialized titles. Really ensures the exact opposite happens instead all the time.
I submitted and had to edit the title for length—no other changes.
I'm not saying it's your fault, I'm blaming the site. Even the automatic title changer very frequently removes words from titles that completely change the meaning of the title. It's really frustrating.
Interesting. I don't recall any of my submissions had an auto title change.