Re: Let there be.....Ignorance? @ fredds
"No evidence for primordial soup"
Umm nope. the "primordeal soup" is a concept which is, as Sir Terry et. al. put it, "Lies to Children". It does not exist, but it makes a great visualisation into some really complex chemistry which would have most people run for cover. So no, you wouldn't find it in the fossil record.
"amino acids do not spontaneously form proteins"
On the contrary. They simply do not do so at what we nowadays refer to as "standard conditions". But the conditions on earth in its' infancy were vastly different, and conditions then were perfect for polymerisation reactions for millions of years. So polypeptides and RNA chains could easily form, in fact it would have been near impossible to stop this from happening since the basic peptides and nucleotides form spontaneously from basic stuff like methane, cyanide, CO2, and H2O under those conditions.<br>Ah wait... there is your "primordeal soup"....
"Scientists estimate 80 proteins needed for the simplest conceivable living cell to function. "
Yes, and you'd be surprised how simple the structure of those proteïns is. Quite a lot of them are built up out of "lego brick" like parts that can have a surprising amount of variation in the peptide chain while still maintaining their "bioactive" shape.
This is besides the fact that we're talking "modern cells" here. There's plenty of suggestive evidence that the first "proto-cells" didn't need full fledged proteïns as we know it, but rather used RNA/polypeptide complexes, which are bioactive in quite a few configurations without any cell structure at all..
"How are you going to get the correct number doing the correct job in the same place. A membrane is needed to enclose them, but it must pass the correct nutrients in, and waste products out; how does it know how to do that by accident.Then the cell must have enough DNA to replace its proteins, and to replicate itself. All by accident"
Still random chance, I'm afraid. You're assuming that a single cell must have evolved all this complex machinery at a single instant. It did not happen that way. Rather, a couple of proto-cells evolved to do one trick really good and "coöperated" with other proto-cells who made use of the "waste products" for their particular parlour trick. This process of "passing the buck" for mutual benefit can still be seen today. A nice example is an E. Coli - methanobacteria symbiosis which gives the methanobacteria the anoxic environment they need to survive, and the E.Coli a way to sustain itself under nutrient-starved conditions. It also gives us humans the rather risky parlour trick of Lightable Farts..<br>The ecosystem near black smokers are also a nice example: chemotrophic bacteria are incorporated in the cells of "higher" organisms, giving them te ability to exist in otherwise rather harsh circumstances.
As a matter of fact, the eukaryotic cell is in fact a symbiont composite. The "organelles" are in fact remnants of once-autonomous (proto)cells which have specialised into a specific task. The mytochondria even retained part of their DNA for that purpose.
DNA is actually a johnny-come-lately when it comes to cellular processes. In fact, the nucleus can be seen as an organelle that has specialised in storing and transcribing DNA. DNA is just "memory" , the actual lines of code is made up of RNA. DNA is not bioactive, which is why it is (almost, there are RNA viruses..) universally used in cells for storage. RNA, being bioactive, is way too dangerous to have it gallyvanting about in your carefully tuned system, and the nucleus has some pretty nifty mechanisms to keep the stuff on a short leash ( and recycle it as well... efficiency is everything.)
Bacteria do not have a nucleus, but the actual mechanism of storage and replication of DNA is exactly the same. They also have the nifty trick of excising bits of DNA into plasmids and exchange them with other bacteria. Sort of a trick-exchange program. And we haven't even gone into viruses, plasmoïds, and other forms of "life" that can provide a cell with a new "trick" which may make it more suited to its' environment, and as such works as an amplifier in the emergent system we call "evolution".
So you see... Random chance, basic physics, and a thorough understanding of biochemistry and microbiology can explain the "how" , quite easily.
"Just about every living thing appears suddenly in the fossil record, with no gradual lead-up. Look up Cambrian explosion."
You need to have something that can actually fossilise to have it show up in the fossil record. Single-celled organisms do not fossilise unless they got solid bits in them like diatomae. (the white cliffs of dover are, in fact, a mass grave of such organisms).
There are actually quite a few bits of fossil evidence from before the Cambrian explosion, you might want to look them up yourself. There's some visible on australia's coast. But most of the early evidence of life exists in the fact that life itself has a tendency to do funny things to isotope ratios in places where it exists. Which in turn can be detected by boffinry that's outside of my chosen specialty/youthful sin.
So you see. There's plenty of scientific evidence regarding the pathway of macro-evolution. It simply takes a bit more than a Wikipedia article to actually Grok it.
[Still Lies to Children, but more in-depth would be....urgh...]
Biting the hand that feeds IT
