A predator discovers its prey easier if the prey moves than if it’s still. A hare, therefore, remains dead calm, close to the ground, when a predator is near. Then it’s almost impossible for either predator or human to catch sight of the hare.
If protective appearance and behaviour are inherited traits, they will be transmitted to future generations. If individuals with these characters survive better than others, then after many generations most individuals will have acquired these characters.
We imagine that this occurred during previous generations as well. Therefore, the hares we see today are well adapted.
Ironically, the predator's hunting habits play a pivotal role in making different species of prey well protected against predators. The predator selects less well camouflaged individuals, thus making the prey better camouflaged!
This course of events is an example of what scientists call "evolution by natural selection".