There was an attempt

Actual explanation: these squid are transparent normally, but can turn on a dark pigmentation when that is a more effective camouflage. Being transparent works quite well most of the time, but if the predator has its own light source (as several deep-sea predators do) then their transparent state becomes a problem, because it's relatively reflective compared to the water around them. In this situation, turning on the dark pigment helps them blend in with the dark water better.

Source: Zylinski and Johnsen "Mesopelagic Cephalopods Switch between Transparency and Pigmentation to Optimize Camouflage in the Deep"

Fixed link. PDF
Edit: interestingly I think your link as formatted will work on the website but not in Sync. Can anyone else report if this is the same for other apps?
OP's link for posterity:
Source: Zylinski and Johnsen "Mesopelagic Cephalopods Switch between Transparency and Pigmentation to Optimize Camouflage in the Deep"
- Android.
  Connect app: a blank page both times
  Mobile FF: a pdf both times
  Seems like my app just can't render files.
- Huh, not sure what's going on there. It looks fine on my instance obviously, but it seems fine on yours and the post's in the browser at least. Then again kbin seems to be particularly janky with links in particular. Thanks for making a version everyone can see
- Voyager/iOS has no issue with any of the link formats.

If squids can turn transparent, why do they bother with all the colors and camouflage? Maybe it's just because they like to show off

Transparent can still be more visible than good camouflage. Just look at how well they can imitate rocks and similar debris: https://youtu.be/q8xJ13pAZNw
- Holy hell. So I guess cloaking technology already exists, it's just that the octopuses got to it first.
Maybe transparent is maximum effort? (I have no idea, I'm just guessing.)
- Suspicious username...
They typically can't. Scientists genetically engineered some squids to have transparent skin, and since their innards and blood are basically already transparent, this is the result.
I don't know if these genetically modified squids can still change colors though.
- sauce?

Interesting. Now, who do we thank for this post? checks notes

The hero we deserve.
I had a cat a while back that was in heat when I first got her. She spent pretty much that whole week running from the front to the back of the apartment and back to the front, looking for a male. She was a poor horny cat.