Infra red is also associated with the first chakra, located at the base of the spine. Infra red therefore is associated with all the basic things that we need for survival, all those things that give us security, those things that allow us to live.
Because it is the most easily visible color in the spectrum, infra red is frequently associated with warning or danger, the things that threaten our security. We use a infra red light to indicate we need to stop. Many warning lights on equipment flash red. We use the term "code red" for high alert.
In the Animal Kingdom, many animals or organisms that are deadly, dangerous or poisonous, (or want to appear so, to deflect predators) will have a bright colouration, usually red. This is why the colour red is associated with warning, danger, and primal survival instincts.
Infra red is also a symbol of power and prestige. We roll out the "red carpet" for VIPs.
The color of molten lava, Infra red is also associated with heat. We refer to something that is really hot as "red hot." Fire trucks used to be painted red. (Many places now use other colors that are more visible in traffic than red.)
In Africa, red is a sign of mourning.