There are few things in the world that are so certain as Evolution. For the vast majority of the world, including the Catholic Church, there is little doubt that Evolution exists. The mechanics that underpin it may not be fully understood (though it very much looks like they are) but regardless the overlying concept is basically unquestionable.
There is more evidence for Evolution than there is for Gravity, for the Atom, and just about anything you may take for granted. It’s a beautiful field of science and the implications of the entire thing is a millions of year old marriage of time and matter. A harmonious entwining thread of life and death that perpetuates positive traits and phases out negative traits.
I’m going to try and explain it to the best of my abilities but I cannot do it justice, this is something you should really talk with a biologist about because anyone with a deep understanding can paint a truly fabulous image.
Evolution has a simple basic statement. Each birth is a combination of the DNA of the mother and the father, this new child has slight mutations. Any mutations that would kill this organism before it can reproduce will be phased out from the gene pool and be a fragment of history. Any mutation that would increase this creatures fertility or opportunities for breeding will, over time, filter through the population exponentially. Lets say that each generation of the organism its mutation happens to let it have 2 offspring where other mutations only lead to 1 offspring.
The first generation it would have double, the second generation it would have doubled that to four, the third generation will have doubled that to eight, and within ten generations you are looking at one thousand and twenty four offspring versus ten.
That is a very weird example because any species that only has one child will not be producing as many offspring as it is losing organisms. You could presume the above example is of each coupling but that would make the gap ever larger.
Evolution can be seen in bacteria in our own lifetime. This is something that I think many people overlook, they think of evolution as this millions of year long process, which it is for large organisms. The length of time it takes to see evolution in action is directly related to the gestation and breeding speed of the organism. If you have something extremely short lived with extremely high reproduction speeds you will find evolution happening at high speed.
Evolution is not a force but a process. Not a cause but a law. – John Morley
The rise of antibiotic resistant infections is something that leaves me in awe. One of the most obvious examples of evolution in our own lifetimes and an extreme example of why everyone needs to know how it works. Farmers have been pumping antibiotics into their cattle in the US and have in doing so created a very fascinating environment.
At its core there are 2 options for an organism, it either lives or it dies. If it dies its genes cannot survive in the environment it exists in. If it lives it is “adapted” to that environment. Now in the case of seals, or hawks, or whales, you may have a creature that does not breed quickly enough for this to be a major problem. If they end up in an environment where they can breed quickly and freely humans can hunt them to reduce their numbers to keep them in check.
However bacteria breed at blinding speeds. A single bacterial cell can divide once every twenty minutes or so. Lets say you have a cow that is carrying strains of infection that can be passed onto humans (increasingly common since we began stuffing them with corn), if you pump them with antibiotics you are likely to kill off most of the bacteria in them.
But what…if one survives?
This single mutation of that bacteria can survive in the environment of those antibiotics, so then what happens an hour later? You have 8 of them…and then what 2 hours from then? 512 of them. By the end of the day you could have ground up a cow that is carrying billions of bacteria that can no longer be stopped by antibiotics.
So what then if someone gets sick with them?
They either get better or they die.
This is the danger of not educating farmers or anyone with large-scale access to biomass. Every single person needs to know how evolution functions. At its core it is incredibly simple and it is incredibly real.
You are born with mutations and those mutations either help you or they hinder you. Any hindrance that comes after the average breeding age of a species will be carried from generation to generation unless it itself mutates and starts killing them off before they breed, which will only leave those with the less dangerous form of this mutation breeding.
This is why most human diseases do not kill people outright, they need time to spread or they do not survive at all. Any disease that kills someone immediately will end up causing its own extinction. This is also why any disease that does pass from animal to human is usually very bad. These diseases are not adapted to our biology and can end up thriving far better than they do in their hosts. In their hosts they hurt the host through their processes but not enough to kill it before it can pass them on to the next host.
Bacteria and other parasites live in a remarkably fascinating plane. We are in essence planets wandering around the universe of Earth. They travel from planet to planet eating up all the resources and ditching before the planet collapses. This is their reality, not something malicious but all they have ever known. Your death is the end of existence for billions of organisms.
So to end lets look at the question “Where do we come from?” I’m going to take a stab at explaining the sequence of events (simplified) between the big bang and our lives.
Time changes everything except something within us which is always surprised by change. – Thomas Hardy
The universe expands violently (known as the Big Bang, another OTTO someday), an incredible pool of energy begins to cool and it coalesces together into giant gas clouds. These become the hearths of stars, those stars grow and die exploding violently across the universe. At some sizes molten matter coalesces into ovoid spheres which cool.
One such sphere is a hostile hell scape known as the Earth. Much like the rest of the universe this planet is powdered thickly with the elements essential to life as we know it (the big 6). Millions of asteroids and comets over time unimaginable pounded the surface and left behind ice which melted into water. Creating the fundamental building blocks for life requires a lot of energy. However the universe had this energy in spades in the form of asteroid and comet strikes. The amount of energy expelled by these things can easily be many hundreds of times more powerful than a nuclear blast.
Much like evolution this happened over and over again until finally something stuck. A single simple protein chain. Suns fuse atoms by their nature and these proteins began reconstructing themselves in much the same mindless fashion. Unwinding and replicating over and over.
This process branched out, with each series of self replicating chains you have exponentially expanding potential for mutation. Anytime a mutation provides an advantage it becomes dominant, because it must become dominant. It’s a self fulfilling situation.
There are very critical points in this chain where things we much appreciate come along. Every complex process we enjoy (or hate) is a giant lego building of these small steps over millennia. In some cases there was an advancement that had a different previous purpose and a mutation to it caused the organism that was birthed to be very effective at either something it already did or something new.
Eventually you get to organisms we can see, the sea fills with predators and prey. Each one is in an arms race with its opponents. Not because they wish to be but because anytime one of them ceases to be they cease. to. be.
The sea is now utterly flooded with predators but the surface is remarkably unspoiled. Some organisms evolve the ability to momentarily survive on the surface. Perhaps they leap out of the water onto land and wait for their predator to leave disinterested and then a wave or their own flippers putter them back into the water.
Others start laying their eggs on land to better their chances for survival. With each generation you find a few that mutate in such a way that they go another inch or two inland. After a million generations you are now looking at creatures that are comfortably 189 Miles inland. They’ve likely forgotten all about the sea, metaphorically speaking.
Overtime the land becomes inundated with predators and prey just like the sea. Some species begin to mutate and use the sea to escape their predators, or to find more food, more food leads to more biological resources which means higher levels of fertility.
Over time this species branches and one set goes into the water and the other goes extinct. Or perhaps the one that goes into the water dies off. It is only known in the aftermath which mutation took the best route. This is how you end up with animals like Whales having leg bones.
Fast forward to a particularly important continent in our history: Africa. At some point in our past a distant ancestor came across incredible wealth of resources. Incredibly high levels of fats and other nutrition, some new prey perhaps or a fertile boon that leaves them engorged in nutrients.
The more calories you take into your body the more free radicals you produce. This is one of the brutal ironies of eating, the more you eat the faster you die. Obviously in the other extreme starving to death is quite a fast way to shorten your life but if you were to restrict your calorie intake you would likely outlive most people you know.
Mutation, mutation, mutation. Humans no longer needed vice like jaws and so those that mutated to have shorter jaws but larger brain cavities were better at something. That something made them more likely to breed, perhaps women back then loved brainy men?
With each further mutation and each growth in brain size you are left with creatures many times more clever and dangerous than their ancestors. At a certain point we end up with only two major species of humans, likely because of combat to keep control of resources. Until a certain point where one of these species utterly slaughters the other.
That mass murdering species? Us. Homo Sapiens.
At a certain point humans took on a secondary form of evolution through written and spoken language. It was at this point that evolution split to two primary fields. Biological and Technological.
Biologically I can’t really tell you what is happening with humans anymore, the same forces that have been still are and humans are still evolving but it remains to be seen which mutations are the ones that are becoming most popular and successful.
Technology is perhaps the most beautiful example of evolution that I can think of that anyone can relate to. If you go back to “the beginning” of written human history you have the vast majority of humans not involved in technology. The analogous example would be a brand new mutation (to someday be known as a species), over time communication improves and more people learn to read and write which means more people are involved in technology (the species breeds), and with each improvement in communication you get a return of exponentially growth in technology (likewise each doubling of a population is exponentially more extreme than the previous doubling biologically).
Before you know it in the span of a single century you have people going from horses, to cars, to planes, and then landing people on another terrestrial object 238.9K miles from Earth.
Exponents is the missing variable for many people. When they think of evolution they try to see how small changes could ever lead to something as complex (and, frankly, batshit retardedly laid out) as the human body. But you need to think in exponents, how quickly does 2 become 1 million. Quicker still does 1 million become 1 trillion… [In fact I was being generous and erroneous earlier, if we assume exponential growth a single couple leading to pairs that each breed pairs would read out as: 1, 2, 4, 16, 256, 65,536, 4,294,967,296. That is the true power of evolution and once you take into account 4 billion tiny tweaks to something you may well never believe it is any way related to its great ancestor.]
Your own mind is crucially entwined with evolution, if it ceases to evolve its understanding of the universe it will cease to be relevant in that universe.