In Artificial Intelligence studies, your studies are not complete until you understand the Evolution Heuristic.
A Heuristic is a strategy for approaching a problem. Unlike a logical statement which must be either true or false, a Heuristic is neither true nor false but instead an approach that works or doesn't work in a specific situation. What works in one situation may not work in another with different parameters.
The Parameters for Evolution are:
1. It must operate on a population rather than an individual
2. There must be a source of change repopulation and recombination
3. There must be a test of fitness applied at the individual level
4. unfit individuals must be eliminated from the population in some manner.
3 and 4 when applied together form the "Test to extinction" hypotheis of the meaning of survival.
It is obvious that most people do not understand evolution so they often talk as if individuals were evolved.
It is also obvious that people mistake the guidance of the heuristic to come from the source of change, rather than from the test of fitness.
To consider why this might be the wrong approach, imagine a statistical scatter graph of a random population based on any parametric property. Now mark a location as the top of the graph, and turn the graph so that location is at the top of the page. Now draw a line through the graph from top to bottom on the right hand side. This is the population that has been selected as unfit.
If you recombine the remaining population some of the new population will fall over the line an be considered unfit, over time, the new populations will gradually lose the ability to recombine to form variations that fall over the line. If we look at the new resulting scatter graph, we will see that the graph has moved to the left. It is however just as scattered, it just no longer contains the variations that used to fall over the line.
Randomness is direction neutral, but fitness is not.
If you understand that, then you will see that Evolution is very similar to a hill climbing heuristic, or a controlled descent heuristic the primary difference being that it is based on survival.
Survival however is not easily understood as a fitness measure, unless you understand Entropy.
The Second Law of Thermodynamics states that nothing happens unless it makes the Universe a little more entropic. A corrollary is that the more entropy is promoted by an event the more likely that event is to happen.
Organisms exist because they increase the entropy of the world significantly while reducing the entropy internal to themselves. One way of looking at it, is organisms export entropy. So do societies, if you want to see an example of this all you have to do is look at E-waste. People here in civilization all want a fast computer, as a result computers are constantly being replaced with faster ones, causing the old computers to become obsolete. Here we see it as buying a new computer and recycling our old one.
In china however, what is seen is large shipments of E-Waste that are stripped in primitive conditions in order to recover the valuable materials. This creates pollution, which makes china's industries unsuitable for making toys for our populations. In other words our tidy little management of E-waste here in first world countries, promotes pollution in second world countries and third world countries. This is the entropic cost of being a first world country.