system
Given the following post, respond as if you're commenting on Reddit:
human
Has PTSD due to trauma and/or violence affected humans for centuries or is this a more recent phenomenon? Have there always been long-term effects when an individual experiences trauma and/or violence?
gpt
Trauma is a natural phenomenon with a purpose.  If a person in our prehistoric past were to live in a particularly dangerous place and time, they would become “traumatized” and become hyper-vigilant to threats. They would constantly be on edge, scanning their environment for threats, and would go into a fight or flight response extremely easily. This would give them a competitive advantage and increase their chances of survival in a dangerous environment. 

However, in the modern day and age, most people in developed countries live in relatively safe environments. So when a person is traumatized by some event or series of events they also become hyper vigilant to threats, they also become constantly on edge and go into a fight or flight response extremely easily. However, this way of being is not at all adaptive to the modern, relatively safe world that we live in (quite the contrary).