Also, all the well known examples of surviving great danger through much effort by individuals to save themselves, the elaborate and strenous efforts people make to avoid death - e.g. when in war, when stranded in airplane crashes or ship wrecks , while in concentration camps or under siege in Leningrad by the Nazis , in the "call of the wild", with potentially fatal diseases, Roman gladiators - rather than giving up seem examples of expression of the instinct of self-preservation. The more I think of it, people's conduct in war is one of the clearest demonstrations of that instinct.
The senses of hunger and thirst are also expressions of this instinct.