Evolution
and the "Theory" of Evolution
Darwin (and others) realized from their observations of nature that animals "change" over time... by that I mean that the children of animals are different from the parents.
The parents are different from each other. This observation is not really so amazing since we all have made it.
We are not exactly like our brothers and sisters, nor like our same sexed parent. So what?!
Well, Darwin (and others) realized that over time, the differences that occur between parent and child seemed to drift. Not all children survive. The ones who do not survive to have their own children are GONE.
The ones who do survive and have children are the source of ALL living animals we find now.
All this seems so obvious that it does not really seem to rate being a "theory".
It is just the way things ARE.
But Darwin (and others) realized that over the enormous amount of time that life had been on earth (as proven by the FOSSIL record, which has fossils of animals that have never been seen in recorded history!) the CHANGE that could occur between a parent and its distant descendants could be enormous. Enormous enough that humans and apes could have a common ancestor. That whales could have been land animals who returned to the ocean. And DARWIN thought he knew why sometimes enormous changes would occur.
The "reason" is called "Natural Selection",which is often misunderstood as "survival of the fittest". Natural Selection IS survival of the fittest, but only when you understand that the term "fittest" only means "the ones that survived to have children of their own."
So is that a controversial theory?
Survival of the ones that survived.
The only problem is that there are a LOT of people who are making a living by pretending that this does not happen. They call themselves "religious", and have their own idea of how things happened, based on wishful thinking and maybe a book (THE BIBLE).
But they have no way of modifying their belief to fit what ACTUALLY happens. What we all can observe. In actuality, they do not care what ACTUALLY happens, they care if you agree with them or not.
Therein lies the genius of Charles Darwin. When faced with the possibility that another biologist would get credit for "discovering" natural selection in evolution, Darwin was willing to face the opposition of organized religion, which considered MAN unchanged since Creation, and Creation itself only a few thousand years ago!
He knew it would be personally difficult, and it was. And IT STILL IS. For the main and simple reason that religious folks do not CARE what actually happens. They want to BELIEVE whatever, and they DO. There are numerous human individuals who will offer to guide you as to what his/her OMNIPOTENT god wants you to do... always coming up with some plausible reason why an omnipotent god could not just deliver the message directly.
Or why an omnipotent god prefers that a simple majority of humans do NOT believe in him/her/it. Do we need a "man in black", maybe with a long beard, or an expensive silk suit... a guy who lives off his power, using it against anyone who disagrees with him, and often using it to get money and women (lots of one or both).
By now you might be wondering, "If natural selection and evolution are THAT SIMPLE, what is the point? what difference do they make?"
Both those are good points. But more important is what difference they do NOT make. You (or I) cannot look at an individual and tell for sure that he/she is not "fit". A baby born with its nose on the back of its neck might look like a disaster, but if we all have to start swimming most of the time, that nose position might be useful ("fit")... and the same can be said of most "defects" that do not prevent having children.
Example: Cystic fibrosis is known to be caused by genetic instructions which make the mucus thick... this causes problems in most people who have cystic fibrosis- complications related to the thick mucus. Most scientists think that the common occurrence of the gene that causes this is because of an advantage it offers when you have only ONE of the genes... there was a time in human history when slightly thicker mucus may have helped defend against some kind of enteric disease. And it is not impossible to imagine some situation in the future when people with TWO of the cystic fibrosis genes have an advantage... it does not seem to be true today... but sudden changes can occur, and often without warning.
While we may think that the biggest and strongest and fastest is the most fit... it is easy to imagine a situation where the small puny animal that can sit out a drought or famine is the "most fit".
Most people who have had some science education believe that he/she understands evolution. But just as certainly they do not. They have some preconceived notion of what is fit and what is not fit. Or they find some single reason why a characteristic was favored... ignoring that the ONLY thing that counts is survival long enough to have children that survive long enough to have children that survive long enough ... well, you get it?
The fact that a human dies at age 20 does not mean that he/she is not fit!
The ability of a human to survive to age 100 does NOT mean he/she is fit!
Evolution does not care what YOU think is good or bad.
It is the ultimate filter of humanity...
And if it is operated by some GOD, it operates just the same.