Updated: Feb 11, 2022
Modern life has changed our environment so much that we do not know ourselves.
We find ourselves expending so much emotion on things that do not benefit us because we evolved feelings that drove our behaviour correctly in the past - today, we continue to trust these feelings but some (like revenge) are not suited to modern day life.
We have to take a look at the human animal from an evolutionary perspective in order to see that our bodies and our minds evolved through a long series of tiny adjustments to an ever changing set of needs. In this context, I find it useful and enlightening to perceive behaviour as an organ. That is to say, it is an adjustment to the organism that confers better survivability. Whether this adjustment is made to a physical or a behavioral part of the organism - is immaterial for the sake of discussing evolution.
The evolutionary niche that we have "chosen" to fill is the "explorer" animal. That animal that seeks new ground and finds new ways to get by in new conditions. We fit in - exactly where we do not! (because our species' specialty is to adjust to the as yet unexplored).
I think, that movement-and-change is both our drive and our charge, as a species - and now that we have circled the globe - we turn our gaze to outer space. Naturally, something deep inside is saying - "if it is uninhabited it's for you".
But ever since cave wall drawings we started changing our surroundings to remember things. We have been modifying the earth to better suit us and as a result we have very quickly created a largely urban society that is very different from the one we evolved in recently.
But the brain circuits to run old behaviours are still there... That is "The Mismatch".
In the realm of psychology "the mismatch" in its entirety is called the full set of "cognitive biases".
These biases represent the difference between human behavior and the behavior of rational agents. Rational agents will always choose what is best for them. Humans sometimes choose what is suboptimal or actually bad for them - this is due to biases.