Since the graph list "web sources" as a source, a cursory web search of "danger sign + region" reveals that red seems predominant in danger signs from:

- India: http://3.imimg.com/data3/II/GU/MY-762554/danger-signs-boards...

- Asia: http://cache4.asset-cache.net/gc/152921698-warning-these-sig...

- Africa: http://www.lifeloveandsugar.com/wp-content/uploads/2015/06/d...

- Middle East: http://cache3.asset-cache.net/gc/474346969-an-israeli-sign-i...

Possible, on the other hand traffic lights around the world have pretty much standardized on:

- green/blue: safe/go

- (optional) yellow: caution

- red: danger/stop

I don't know of any country where this convention is not in use.

As I learnt looking into the indicators the accessibility of traffic lights had a lot more to do with their vertical position than their colors. Can't use solid green, yellow and red if we want them to be understood by people with various forms of color blindness.

But you could make colorblind-friendly color schemes available through plugins instead of making a slightly more confusing option default.

Do you mean the weather icons? They are not the alternative to properly designed status indicators. Take a look at this https://jenkins.io/images/post-images/blueocean/pr-view.png

There's more about why and when we use them in my other comments.

Look no further than mother nature, where bright colors often mean WARNING, I WILL MESS YOU UP. A few things to look up as examples:

* Rosary Pea

* Coral Snake

* Stag Beetle

* Jerusalem Cherry

* Phantasmal poison frog

* Strawberry poison dart frog

* Bittersweet nightshade berries

The Coral snake is debatable: it is so deadly that no animal can "learn" by getting bitten by it.

Instead one theory is that the mimicry is in reverse: the coral snake is mimicking the non-fatally venomous "false coral snake" which is also more numerous.

There are a variety of different theories on mimicry, and the science of the coral snake is still debated...