Posts Tagged ‘genetics’

God vs Evolution; Inherited Gene Mutations

November 21, 2010

The key to exposing those processes of evolution that appear completely nonsensical if attributed to an intelligent designer is to ask these two questions;

1. If God designed this, what would he likely have done? And
2. If the process of evolution produced this, what would be the end result?

A great example of this is the case of every living thing eating every other living thing just to survive. If I assume as a basic foundation that God is a loving, caring individual and really likes humans more than anything else, then one would have to guess that he would not design an entire ecosystem where the primary goal of each member of that system is to kill and eat one of the others. Humans are just “food” to a number of viruses, bacteria, parasites, scavengers, and large predators. While this appears to be a perfect characteristic for an evolutionary process of competitive consumption and mutation, it’s entirely moronic from the perspective of any sort of intelligent design. Add to this the fact that some vegetarian humans choose to avoid killing any other animals and it tells us that it is, in fact, possible to have an ecosystem where nothing kills anything. God was just too stupid to figure it out. There are quite literally thousands of species of scavengers and insects and plants that eat nothing but already-dead organics. Wouldn’t that be something; an ecosystem where animals would only eat each other after they died from other causes?

Of course, an evolutionist would argue that this could not stand; eventually one animal would evolve the brilliant trait of killing other animals to assure their timely death, drag the carcass off, and nibble on it only after it had decomposed to an edible state, like a pheasant hanging in front of a British butcher’s shop. Killing to eat, as you can see, is an inevitable state of evolution, not the hand of intelligent design. But this, again, assumes that an animal could naturally evolve at all without God’s thick fingers in the dough. Even if God had started with such a benevolent, non-violent system, mutation and evolution would inevitably have driven us in the direction that it has.

So, again, look at the questions; How would God design something, and how would evolution mould it?

Take genetics. There’s the obvious fact that every living thing, even viruses, use DNA, and use the same code sequences that all the other organisms do. The gene that makes haemoglobin in humans is very much like the gene that makes haemoglobin in pigs, and in fact can and has been spliced into pig DNA so that the pig had both human and pig haemoglobin coursing through its veins. The genes are just little strings of codes, and the fact that genes that do the same thing in each animal tend to be nearly identical should be a pretty obvious clue that evolution, with its accumulation of mutations, has been at work. However, the ID proponents will tell you that God has merely taken a good design and used it elsewhere, tweaking it for that particular organism.

So the ID argument is founded on the idea that God can apparently pick and choose what genes he wants to use in each animal. After all, he designed them, right? We might expect each animal to have its own unique genes, with common functions duplicated in between species as very similar genes.

But here’s the problem. If there are 5 genes in a Human, let’s just call them A, B, C, D, and E, and we compare them to their functionally equivalent genes in a muskrat, we would expect some variation between each pair of common genes in the two animals. If God can just pick and choose genes and tweak them to his heart’s content, we would expect the Human-A gene to be different from the Muskrat-A gene by some percentage, like 5%. Evolutionists would consider this 5% as an accumulation of mutations after splitting from a common ancestor. The B-gene might be 20% different, and the C-gene 50% different. And so on. God can pull genes from anywhere and do anything he wants with them. So any level of variance between two genes between two animals would be possible, right?

Wrong.

What we find is the answer to “what would evolution do?” question. If two animals descend from a common ancestor (well…they ALL do), then we would expect a certain mutation rate to occur in the genes of the each animal, a “molecular clock”. All the genes in the animal would maintain this same rate of mutation accumulation, being exposed to the same mutating environment, the same statistical distribution of unexpected change. What we would expect is that the 5 genes between human and muskrat would have roughly the same percentage difference for each pair of common genes.

This, not surprisingly, was the result of an experiment done by David Penny and published in 1985, using 5 genes which were so similar between species that they have the same name in each species (the experiment is described by Richard Dawkins in The Greatest Show on Earth, page 322). Except they checked the 5 genes across a group of 11 mammals. The results were as mentioned above; for a given pair of animals, the number of mutations in similar pairs of genes were consistently close to the same percentage across all 5 pairs of genes. Other experiments since then have expanded on Penny’s work, with similar results. Incontrovertibly, it points to the FACT that each pair of animals had a common ancestor and accumulated a statistical average of mutations since the speciation event occurred.

What it does NOT show is that God picked whatever gene he felt would help the animal survive best and slap it into the animal’s DNA matrix. This would have given totally different results, with a broad variance of mutations between pairs of similar genes.

This experiment, above and beyond any other experiment I’ve read about, proves beyond a doubt that ID is bogus, and evolution suitably describes exactly what we would expect. There is no intelligent designer picking and choosing; there is only a random, statistically averaged accumulation of mutations weeded out by competition and speciation events.

If this isn’t enough of a nail-in-the-cofffin for doubters, there is the issue of viral scarring in human DNA, which not only hammers in the last nail, but buries the coffin besides. Retroviruses have a nasty habit of inserting their own code into the human DNA sequence. Estimates are that 8% of human DNA (of the 95% that’s considered “junk DNA”) is viral in nature, inserted in the past by retroviruses. This portion of our DNA is, in essence, a fossil record of every virus that humans and their animal ancestors have had to fight during their long history.

It should be pretty clear even to ID proponents that God wouldn’t go out of his way to add inert viral sequences into our own DNA. However, just the fact of its existence is not the telling point (although it isn’t a bad point by itself).

Viral scarring in DNA shows up in the same place in the gene sequence in different creatures with whom we share a common ancestor. Apes and humans, humans and rats, if you look, you find that both species carry the signature of ancient viral attacks that left a physical scar behind, inserted in exactly the same place in the equivalent gene in both animals, a viral attack that occurred before the two species went their separate genetic ways from their common ancestor. Here you have two different animals that both just happen to have the same viral-scar in the same place in the equivalent gene in both their DNA sequences; only an evolutionary process can explain this.

The fabrication and rationalization of an ID proponent could only stretch so far before it shatters into nonsensical fragments while attempting to explain these evolutionary results. The fact of evolution is sealed in genetic documentation, a book merely waiting to be opened and translated into the history it provides.

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Are There Two (or more) Living Species of Humans?

November 9, 2010

For those of you looking for some racist rant, you’re not going to find it here, despite the interesting title.

Here’s the conjecture; there’s a lot of genetic diversity in humans. Is there enough variation between humans to prevent two of them from producing fertile offspring, and if so, could they be considered two different species of humans?

Amongst the seven species in the genus Equus, we know that horses and donkeys can breed together, but always create sterile offspring (mules, that is). Likewise, zebras and donkeys have produced the “zeedonk”, which is also sterile. The definition of a species separation is that two animals from separate species cannot produce fertile offspring. Sterile mules and zeedonks, fine, but you won’t be seeing a purebred line of mules any time soon.

So theory has it that speciation occurs when two groups from one species are separated for so long that accumulated mutations in their DNA prevent them from making babies effectively, or making effective babies. It’s actually senseless to speak of two species that can crossbreed, because then, of course, by definition they are the same species.

But here is where it gets interesting. Let’s break a species up into tribes, or herds, whatever. What if tribe A can breed with tribe B, and tribe B can breed with tribe C, and C with D, and D with E. But they are spread across the country, and though there’s been some local mixing, tribe A is so genetically different from E that they can’t breed at all. Are they then different species? If a meteor came along and wiped out B, C, and D, then there would be no doubt at all that A and E were now different species. And yet, if you plopped all these tribes into a city, you would only have a statistic for “infertility” between certain members that appeared to be unable to produce fertile kids; the Zeedonks of the human species, the chance meeting of a type A and type E person.

So it’s entirely conceivable that all humans could mate with 99% of all other humans, but would qualify as a “different species” when paired up with any member of the other 1%. Thus, though the species superficially looks like a single species, you could selectively sample two humans and technically prove they are different species, even though each of them could produce viable offspring with a large and overlapping majority of other humans. Wouldn’t that be odd?

It would be interesting and informative to take a broad sampling of genes from both parents of sterile children and see if, statistically, they have a much broader genetic difference than parents of non-sterile kids. It would also be telling to know if children from mixed marriages (racial, not religious!) tend to have a higher incident of sterile offspring. And lastly, if any of this is correct at all, I would expect that the percentage of sterile offspring would be on the rise, because the world has lost its tribal nature and interracial marriages are much more common than they used to be. This should be a fairly easy statistic to locate and correlate with the evolution of travel in the world, with isolationist communities like China offering a valuable “control experiment”.

A problem with this list of data-mining “experiments” is that our society tends to associate sterility with an individual, not with his or her parents. We need to establish a data-base of genetic information that goes back a generation from the sterile individual, not assume that the cause of the problem started with him.

Of greater significance and concern is that our rush toward universal mixing, though perhaps ethically desirable, could result in such an incredible diversity of genetic mixing due to the huge population involved that the norm might become sterility. There may be a maximum population-mixing size allowable before it self-sterilizes, and forces itself into a mass speciation event. Or it could mean the opposite, and human blending will become so complete that there could never be a human Zeedonk. It’s hard to say; the rules of human society have had such a non-natural effect on the rules of evolution that they hardly apply to us anymore, despite the fact that we continue to mutate and evolve, or devolve as medical advances help keep us alive. However, I find the questions that I’ve proposed of weighty enough substance that, hopefully, someone with more intelligence and energy than myself may decide to pursue them to their natural solutions.