We begin with a self replicating molecule. Where has this molecule arisen from? That is clouded with much debate, but once the understanding of what life is we can formulate a much needed hypothesis of where the this molecule arose from.
What makes something alive?
It has to have and maintain cellular Organization. It has to be highly complex and maintain high order. Has to be able to respond to stimuli. Has to be able to reproduce, grow, and possess molecules that can be passed onto children. Must utilize energy. Must be able to maintain homeostasis. And finally, must be able to adapt, evolve, and most importantly, be able to survive. But now the question is what gave rise to a "living" molecule? Was it non-living molecules? The question is complex in the answer, but the short answer is that everything is alive on a subatomic scale. However, the first self replicating molecules arose from bacteria. Bacteria was the first replicating molecule that was "alive". We call this bacteria, Archaea. Because Archaea would have to survive amazingly hostile conditions and these cells have that ability to survive where nothing else can. These are first replicating cells.
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Archaea though ancient creatures are a relatively recent discovery. Modern science only learned about them in 1977 when they were discovered by Carl Woese and George Fox. Far fewer Archaea are known to science than Bacteria, in fact only 209 species were listed in 1999, but now that more people are aware of, and looking for them many more species are sure to be found.The Ancients
Most Archaea are anaerobic (living in the absence of Oxygen) and many live in uncommon and extreme environments, i.e. hot springs, Arctic ice floes, highly saline waters and highly acidic or alkaline soils. Many of the world record holders for extreme environments are Archaea. Their tolerances range from 4(C to 110(C, and from pH -0.06 to 9.5, examples are given in the group synopses. Nearly half of the known Archaea are Methanogenic, meaning that they give off methane as a by-product of their metabolic activity. Though many Archaea (singular Archaeon) live in environments which are hazardous to most other organisms, some live much closer to us and species of Archaea have been found in animal, including in the human, digestive tract.
Surprising there have been many similarities found from the ancient archaea cells and today's eukaryote cells (Definition of Eukaryotes) which is what our genes posses. According to Elizabeth R. Barry and Stephen D. Bell:
The archaeal DNA replication machinery bears striking similarity to that of eukaryotes and is clearly distinct from the bacterial apparatus. In recent years, considerable advances have been made in understanding the biochemistry of the archaeal replication proteins. Furthermore, a number of structures have now been obtained for individual components and higher-order assemblies of archaeal replication factors, yielding important insights into the mechanisms of DNA replication in both archaea and eukaryotes.Science
Through some processes I believe that Archaea cells gave rise through a mutation to Bacteria cells. This would have happened when the earth entered into a state that threw off the archaea's cells natural replication process; a change in the atmosphere for example. Eventually, the creation of modern day prokaryotic cells (Definition here) emerged. And then something remarkable happened. Bacteria evolved into a new strand of cells, the eukaryotes. A highly complex cell that was capable of supporting life on earth creating the dinosaurs, the plants, and eventually the ancestors of man. But wait. What is evolution really? Evolution is a term that has been severely disfigured by religious fundamentalists, laymen and even scientists. Which is sad, because evolution has a basic meaning...
Many people do not understand the true mechanism of evolution. Evolution is not the beginning of life or how life started; but rather it is how life changed over time to create the present day animals that we see today. Evolution at its simplest definition means nothing more than: To Change. As long as change is occurring evolution is occurring. No matter if it is cellular or physical. And it does not necessarily mean progress in the species, it could very well hurt the species or the animal. Change has been occurring for billions of years! We can observe it today in ourselves and following it through our ancestors. The missing link or the beginning ape like creature went extinct probably after the first major evolutionary change into an upright walking animal. We know that animals go extinct all the time and therefore, we can assume with high probability that this first stump of ape went extinct when its newer generation of apes was able to move about easier and access food easier and do things that the older generation could not do.
It is change through a species, very slowly. For instance and example: A male and female human of today mate with each other and give birth to a child with a slightly different genetic trait. Usually the odd genetic trait would be passed down from father to son. Because of the Y chromosome which is basically a deformed X chromosome. This slightly different genetic marker, in this offspring which will be a boy, we will remember as Offspring T. Offspring T then mates with a "regular" woman and gives birth to two more sons. Each of these boys now carry the genetic oddity of there father in Offspring T. Through many more years this gene no longer becomes an oddity, but will eventually become a regularity, through reproduction of that lineage. This will include different prototypical features and genotypes. Now I want to make something clear this will not affect the entire human population! This will affect this lineage alone. They have essentially branched off into a new genetic factor.
A gene that will give rise to a green skin down the line or stronger bones. Micro evolution does occur, but the change will not be labeled micro, because it is no longer micro when it presents itself. It is at this point very prominent and no longer Micro. Of course you may also say that this is adaptation, but then again you would be wrong, because adaptation does not necessarily require change of the genetic structure to keep the animal alive.
Simply. Evolution is Change. It happens. Its biggest evidence is the fossil record. We have animals alive today that were not around millions of years ago.
What was the ancestor of man, why do we have sex to reproduce, and where did the races come from? The ancestor of man was probably many different classes of the same species that were able to reproduce with each other. This cross breeding allowed for a genetic variety, which is something is that a necessity in today's world.
Sex, is an interesting question, for a variety of reasons
But the main reason sex is so important was that it allowed for genetic material to be
purged. And if you are wondering what we evolved from besides bacteria; our genes basically give the answer to that: Viruses. Our DNA is mostly composed of Viruses. Basically viruses are jumping genes (a.k.a Transposons, genes that jump and hook onto other genes or cells and combining with it). We see this today with the HIV virus and how it jumps onto the DNA of our cells and messes it up. We are essentially, at the core of our DNA, a makeup of dead viruses from long ago. Which is truly fascinating. And sex actually arose because of parasites (viruses). In order to combat the parasite we had to find away as a species to destroy the parasites. And that was through sex. Sex purges the genome to protect itself from mutations that threaten the life of the species. A complex process, but a useful tool indeed. And you can find almost anywhere. For instance, with animals that basically clone themselves through the use of A-sexual reproduction, which is just cloning itself. This process is not very useful if the animal catches a parasite. Cloning brings an end to scientific diversity. Cloning becomes more susceptible to the parasites and eventually dies off completely, because the DNA can no longer code itself properly or the parasite morphs itself into a new animal. Again scary, but highly intriguing...
And now the case of the different ethnicity. The preceding statement is a fallacy and by that I mean the genetic material for whites, blacks, asians, hispanics, and everyone is essentially the same. On a genetic level there is no real difference between any of us. But many people wonder where they originated from. That is a difficult question that is best answered by a phylogeneticists, which, mind you is more of a philosophy than a science, but it has merits. And very strong merits at that:
Meet the direct decendants of our oldest relatives. The San Bushmen and a special thanks to Spencer Wells for taking this amazing journey and explaining everything in the simplest terms imaginable:
If you have time please watch part one and the entire 13 parts series. It is incredible
And this concludes the evolutionary and genetic part.














