Stand back, B.Sc in Genetics/Immunology 'a comin'! =)
I admit, I skimmed, but I want to clear up three things right now.
1. The nature of scientific "laws."
2. Abiogenesis.
3. Evolution.
1. Scientific Laws.
The scientific method is based upon creating hypotheses, observing or testing data while controlling for as many variables as possible while manipulating a variable of interest, and examining results for significance (usually statistically) to determine if a generalizable explanation of the phenomenon is produced. Your hypothesis can be false, or it can be supported by the data. A hypothesis CANNOT be true. Truth implies it acts that way 100% of the time in every circumstance.
When hypothesis gain greater support through many experiments, they often become theories. Gravity is still a theory. The three "laws" of thermodynamics are still theory. Kinetic molecular theory (the foundation of modern chemistry, physics, and biology) is still theory. Evolution is still theory.
When a theory gains enough supporting evidence, it is often called a law. That does not mean it is always true, but it does mean that either the violations of it are extremely specific or unknown altogether.
Now, theory in science does not mean theory in lay-terms. Scientific theory is a cohesive, sound collective of facts which explain a phenomenon. It being theory does not mean it isn't relevant or a very important discovery for understanding our world. That's a criticism levelled at evolution all the time - "it's still a theory!" So is gravity, yet I don't see people trying to walk on their roofs and walls.
2. Abiogenesis
Abiogenesis merely states that life came from its chemical components - that simple replicating chemical system were the precursors to the first form of life on Earth. It does not go beyond that.
It's important to note that many of the proposed reactions necessary to create simple replicating biological systems can at present be done in a lab, and dear old Craig Venter of the Human genome project is hard at work on the rest of them.
The foundation of abiogenesis is this: all life is characterized by the ability to reproduce itself. Therefore, the simplest biological system could have easily existed in a primordial soup and merely consisted of self-replicating ribozymes (background: RNA can act as an enzyme, cutting, splicing, and even replicating itself). RNA is quite reactive and quite unstable, so mutations or changes to the chemical structure could have other effects. The characteristic cell membrane and organelles in eukaryote cells would have come much later. Truthfully, a ribozyme capable of self-replication is probably the beginning of life on Earth. Different ribozymes mixing in the chemical soup that used to cover the plant could work in conjunction, each beginning to perform specific functions upon which the others depended. The process simply grew in complexity for there, culminating in cells we know today. Interestingly, there is evidence that prokaryotes (that is, bacteria) are actually a more recent evolutionary product than eukaryotes, the idea being that both developed from Archaea.
3. Evolution
Evolution merely states that life forms change over time. If you deny that, quit reading because you're an idiot. We can watch how organisms change and diverge into new species over a course of a few years under controlled circumstances. Evolutionary theory existed well before Charles Darwin - Darwin's contribution was a mechanism. Previously, people had all kinds of theoris about how life evolved, but Darwin was the one who suggested natural selection.
Natural selection is the process by which some organisms die before reproducing, while others reproduce before dying. Which of the two options depends on how well that organism is adapted to its environment. Those that survive and reproduce pass along their genes to the next generation, while those that die do not. Thus, each successive generation of a species contains genes from only a subset of the possible parentage. EVOLUTION OCCURS ONLY AT THE SPECIES LEVEL BETWEEN GENERATIONS. Organisms are adapted, or not, when they are born. They do not suddenly acquire new characteristics part way through their life span. Evolution typically takes several generations, but can be observed at the phenotypic level (visible traits) in as little as one. Genotypic evolution (the evolution of the genes a species carries) occurs every generation, gradually. The discrepancy between phenotypic and genotypic evolution is why we see punctuated equilibirium in the fossil record - genotypic changes must "add up" before we see a phenotypic change - one gene mutation does not equate to one physical trait most of the time (although for some specific genes it does). Thus, the "gap in the fossil record" is not really a gap at all, but rather the effect of cumulative changes in genetic sequence required to produce a visible change. Example: Physically, we are identical to our ancestors of 100,000 years ago. Genetically, disease, famine, and interbreeding have produced significant genetic changes in Homo sapiens.
Natural selection is visible in a lab within populations that have swift generational time: bacteria, viruses, flies, eels, and worms are all examples of this. We can also point to artifical selection as an example of how evolution occurs - isolated populations breed, and specific traits are passed along to the offspirng of each subsequent generation. Dogs, for example, are a single species which have been selected for when reproducing to produce specific traits, which we call breeds.
The underlying mechanism for natural selection is genetics, which has only been well understood for approximately 50 years (the history of genetics extends only back into the mid 1800s). Humans, as one examply, have about 110,000 genes, coding for millions if not billions of proteins. This occur because genes can be "spliced" to produce different RNAs and thus different proteins. Thus, a single mutation can affect several different proteins, which can in turn affect several different bodily systems. The result is that a single mutation in combination with other mutations can produce drastic changes in the visible phenotype over a single generation.
One more thing: When species evolve, they evolve through either cladogenesis or anagenesis: in cladogenesis, we get two (or more) distinct species emerging from one. In anagenesis, the single species merely changes such that it can no longer be classified as the same species that it was. IN ALL FORMS, WHEN A SPECIES EVOLVES THE ORIGINAL ANCESTRAL SPECIES NO LONGER EXISTS. You seem to think that the ancestor sticks around - it doesn't.
If you still either don't get it, or refuse to believe, I'll grab you a well-executed study where a group of researchers stuck a species of lizard into a new environment and over the course of less than 5 years saw it evolve into two distinct species (part of the definition of species is that they no longer interbreed).
You cannot believe in so-called "microevolution" without accepting "macroevolution." They are not two distinct concepts, but rather two halves of the same whole. I hear this argument from the anti-evolution crowd all the time and it simply screams that you don't actually know what you're talking about, but may have read a book or two or listen to a lecture by somebody else on why you shouldn't believe evolution.
People who don't "believe" in evolution don't understand what evolutionary theory actually says, means, or how it works. A little education would go a long way for those lost souls. There isn't a debate - there are merely religious people who refuse to accept science, and everyobody else who is tired of arguing with them. No serious scientist bothers to debate it anymore because it is a truly worthless endeavour. Thus why I'm not arguing against varied forms of Creationism, but rather explaining evolution.
Oh, I just saw this so I'm adding point 4:
Homosexuality.
All evidence to date points to homosexuality being a product of biology, likely in the nervous system. It is not heritable, but rather appears to be a condition that results from varied forms of early developmental biology. Little known fact: We do not have only two sexes. Religion and science both coined the idea that two sexes are all that exist, but sexual identification both mentally AND biologically spans a wide variety of forms. Intersex, a concept which genetics has brought into the limelight, is a condition where some biological sexual characteristics are male and some are female, in varied proportions (this is not hermaphromatism).
The sole factor that determines sex is a single androgen, a hormone called testosterone. Babies exposed to higher levels of testosterone develop male sexual characteristics; if exposed to lower levels, they develop the default, female characteristics. Chromosomally XY people can be female. Chromosomally XX people can be male. XX/XY is not a law, just the typical default organization scheme nature has produced. In addition, each part of the body must be exposed to the correct hormonal levels in order to develop according to its "assigned sex." Intersexed individuals are a product of androgen exposure in some parts of the body during development, but not others. Conceivably (and this has been hypothesized but not yet tested), homosexuality may result from centers of the brain responsible for sexual attraction being exposed to an amount of androgen different from the rest of the body. Homosexuality can therefore be lumped as a form of intersex, a biologically normal condition that occurs quite frequently in human populations. Homosexuality is therefore absolutely normal, and a product of how we develop.
To top it off, homosexuality has only become a "category" of person since approximately the year 1750. Prior to that, homosexuality was merely a behaviour which various socieites accepted or not depending on their cultural norms. 5th century Athens was a society that accepted limited homosexual practices under certain conditions. A modern culture, the Sambians, practice same-sex sexual acts as a matter of growing up, but it has nothing to do with sexual orientation.
In short, your nonsense is a political agenda promoted by primarily religious institutions to bar the practice of pleasure as a phenomenon which they controlled (gee, do I sound like Foucault yet?
) in order to further control the daily lives and practices of the population they included as part of their organization. In large part, the Catholic Church condemns homosexuality as it does birth control merely because they believe sexual union should produce children, which in turn will grow up to be good little Catholics and donate money to their local church.
The modern conception of homosexuality is a political lie created by both religion and science to further dominate and control vulnerable populations of people.
And that, my friends, is a synthesis of biology, philosophy, and a little bit of sociology thrown in for good measure =)
EDIT: Holy crap, I just looked back at page 20 and saw some of the BS people are spouting about homosexuality and I am genuinely terrified that you guys are not only quoting it but might be believing it. But let me put your minds at rest again:
-Homosexuality is probably not genetic, because there is no indication it is heritable. Breeding has nothing to do with it; conditions can be genetic and not be passed on but still crop up because of little things known to us genetics types as SNPs, or point mutations. In essence, random changes to DNA which occur throught a cell's lifespan.
-As a developmental condition, homosexuality is a variation on intersex, a natural biological condition which makes the Church and conservative moral types freak right the hell out. What, sexual characteristics are fluid and on a gradual scale, not absolute? Madness! Oh wait, so was a heliocentric model of the solar system. Oops.
-Cure for homosexuality? Believe it or not, sexual acts do not exist solely for reproductive reasons my friends. There's plenty of sex, both human and animal, that occurs for a wide variety of reasons that have nothing to do with procreation. I hear homosexuality and cure in the same sentence and I have these horrible flashbacks to eugenics.
-Saying hate the sin, not the sinner, is a cop-out, an attempt to disguise intolerance of diversity and difference under a cloak of Faith. Fact of the matter is that everyone's biology is different in many ways and none is "more right" than any other.
-Because it pissed me off, Captain Jack*ss's analysis of homosexuality as something akin to sickle cell anemia is not only totally wrong, but betrays an underlying ignorance of biology in the first place.
Did I mention I can't WAIT to hear some of the responses to this post? I'm ready boys... I've got PubMed fired up and I'm ready to go, so take your best shot and just pray you got it right because I swear if someone tries to make a biological argument and muffs it up I will crucify them alive in text, pun intended. You have been warned
