coremax wrote:Oracle wrote:The DNA of an African is the same as the DNA of a KKK activist .... and is is chemically, broadly indistinguishable, from that in Bacteria!
Broadly indistinguishable from Bacteria? We're not talking about genome sizes then? You're getting me confused - 'broadly indistinguishable'...
Make an exception for once, and see the link below :
http://en.wikipedia.org/wiki/File:Tree_of_life_with_genome_size.svg
I can't download the tree, but I assume it is standard.
You cannot draw meaningful assumptions on the "genome size" between
different species, only within (intra-) species comparisons. For example, bacteria have a small "genome", but are very successful ubiquitous colonisers, whereas we have abigger "genome" but still struggle to colonise as many environments
(Most of our DNA is Junk anyway, which bacteria have gotten rid of. Maybe as little as 5% of our DNA is biologically functional) .... As I recall, Wheat has more DNA/cell than us and multiple copies of Chromosomes (polyploid), whereas we only have one set of chromosomes per cell. Studies
between different Wheat strains/races are meaningful in terms of their chromosome number/genome load because they lead to different yields of "flour", but that would not be applicable as a comparison to us!
Besides all humans have the same number of chromosomes apart from, obviously, if a mutation has taken place - and this (as well as a few other factors) is why we, unlike some other species, cannot be put into different races.
Why I said "broadly indistinguishable" was because I didn't want to bog the post with details. Once again, I'll leave out as much detail as possible and try and simplify what I mean.
All DNA is made up of four Chemical Bases (some other chemicals too, sugars, phosphates, but they are just a backbone for the important information-involved
Bases) and it is their sequence which gives us the variety on Earth. In that context bacteria and all living species are exactly the same (leave out some viruses for simplicity). Minor modifications can be added to these Bases (e.g. methylation), but these don't alter the
sequence (basic information), they are just fancy regulating mechanisms for switching genes on and off. So, if spooled-out DNA from bacteria or human cells is compared, it would be chemically the same, give or take a few modifiers depending on what the cells were actively doing/not doing at the time you extracted the DNA. Hence, as far as evolution is concerned, the sequence (Bases) of the DNA is the blueprint for the organism's development and also for the regulatory mechanisms (which add/take off the methyl groups) ... which are all encoded via the 4 Bases which are the same in Bacterial or Human DNA.
Are you going to suggest that the fact of evolution in bacteria has covered a wider span, not because of antibiotics and other emerging threats on bacteria, but because 'the research was done mostly on bacteria'?
In effect, since we evolved from these early life forms, we have had as long a span to counter the Earth's challenges as Bacteria. But each time an Individual is "born" its DNA was subjected to the randomness of mistakes/mutations. Since the Earth allows for a number of variables to emerge, if they're not wiped out by the prevailing environmental/selective conditions of the time, they may yield new species/variants. You can
mimic these processes in the test tube using bacteria which go through many generations in a short space of time and introduce "hazards" such as antibiotics. These provide a
test for the evolutionary models proposed for how cells may survive by mutation/recombination, but they were not what gave rise to the Theory of Evolution, which was based on empirical data/sample gathering from macro-creatures.
I am the world's worst communicator, because all I can think of are the 'ifs' and 'buts' which occur with every statement I make, but I tried to focus on what
I think you are suggesting.
So, how about if
you now provide me with
your view of the world and the evidence which has helped you formulate the picture ... and put me out of my misery as I suspect you have some MAJOR point to make which will blow me over