This might help explain a bit. It's not technical and will not answer all your questions but it does give you an idea of the problems in trying to give these answers.
In short, we may know enough to look at two specific genomes and say in general this is probably a bonobo and this a human, but we do not yet know how some of these differences work. For instance, humans and bonobos have some genes that are identical but, for reasons we do not yet understand, work in different ways. The proteins created are identical but under the influence of the full score of proteins in the system these identical proteins do different things in different places within the different species. This, of course, will lead to differences in phenotype just as well as a gene difference. Differences in DNA structure are but a beginning point in determining what creature is being made.
The study of proteomics is the study of the interrelationships of the proteins produced by the genome. As you can imagine this is highly complex and we have just barely begun. To fully determine what makes such a different animal, a bonobo, from a nearly identical genome as a human will be decades in the future.
Faith, just to add some context to Taq's message 62 above:
In the diagram the upper left grouping of atoms is the Thymine molecule. That is the "T" you see in a DNA sequence list. The next one down is the Adenine, the "A", molecule. The next is the Cytosine, "C", and the lower right is the Guanine, "G". The sequence represented in the diagram is TACG and it goes on from there.
To complete the picture there is another molecule attached to each of these that is not shown. An A attaches to the upper right of that top T, a C attaches to the upper right of the G, always T-A and C-G. Each of those companion molecules is attached to another phosphate group (the thicker dark line grouping) which is the backbone for the other side of the complete strand.
Again, my question is what is a "strand" of DNA, how long a strand, in relation to a gene for instance, or a chromosome, etc.
This string of molecules, by the millions, would be the DNA strand or chromosome. Genes are parts of this strand, identified by certain start/stop sequences. Each chromosome contains thousands of genes.
Is there a clearcut pattern to the location of the species-identifying nucleotides in that chain of 20? I mean does it occur at predictable intervals or just show up willy-nilly so you have to sort out the entire strand to recognize them?
No. No predictable pattern. There are long stretched of the genome where every letter is different between chimp and human and there are even longer stretches of code where the sequences are identical. Over the entirety of the 2 genomes there is the 5% difference.
And to muddy the waters even more for you consider this:
Depending on our separate heritages there may be more difference in the genomes between you and me than between you and any specific bonobo. The important thing is where these differences occur.
I'm not sure this question makes sense.
Yes, they make sense. The only questions that don't make sense are those that go unasked. You are doing very well indeed.
Of course I'd really like to know WHICH stretches have different letters and which the identical sequences because I'm very much interested in which traits are involved.
This paper details some of the problems that exist in answering this question. While we can see by comparison the differences in the two genomes we have a hard time telling which differences are significant and which are not.
For instance, we know that there are code differences in some of the genes dealing with brain chemistry, limb developement, digestion and hearing. What we do not know (yet) is which differences have specific phenotypic effects and how these effects are achieved.
And again I'm still interested in where the genes fit into this. I mean they ARE clearly demarcated segments of the DNA with their start/stop codes, right?
Yes they are.
And they DO determine very specific traits in the organism, right?
In combination with other genes, yes.
... he seemed to think mutation could actually change what a gene DOES, whereas I was arguing that the gene always does whatever it does but that alleles change the specifics of how it does it.
And he is right. Genes are the templates for making proteins. Each different allele makes a different protein. The protein is the actual work unit that makes things and does things. Any mutation may cause a totally different protein to be produced that may make/do something unexpected.
This new protein may have a minor simple effect like displaying a somewhat different shade of the yellow splotches you see in the iris, it may cause no display of yellow at all, it may become a red splotch maker or any number of other things. It may be totally dysfunctional and interrupt signal cascades that lead to blindness.
Like if a gene makes eye color its various alleles are only going to determine WHAT eye color and not change that gene into one that makes eyelashes or bellybuttons. Right?
For the most part that is correct but only because eyelashes and navels require a full complex of multiple other genes to create and, further, the cells in the eye are chemically bound to transcribe the eye color genes while the cells in the eyelid are not. The proteins from the eye color genes do not get made in the skin cells or in the hair follicle cells.
But use caution here. We know that quite a few genes (like the vast majority of them) are used to create multiple different sets of proteins from the same single allele and that genes are often used in different parts of the body with their protein products being used for totally unrelated functions.
Re: This thread should be about facts not interpretaions
I did remove the militant "Get off this thread" at least.
That cup of tea we talked about last year does fit you well and I appreciate your action.
"Macroevolution" in relation to speciation is an artificial definitional ploy.
I can't do the same with "speciation" because in that case it does describe something that actually happens ...
Then I am confused, again. You accept that speciation occurs and yet you reject the word "macroevolution" which is the same thing just repeated over and over from one species to the next to the next.
You acknowledge that the "Ark cat" gave rise to house cats, lions, cougars and the like, all of which would have had to be the products of multiple speciation events along separate lines from that original Ark cat. In evolution that is classic macroevolution.
The only difference in our positions is that Evolution posits this process took place over deep time which is something in which you do not believe. But by definition it is macroevolution no matter how much time it took or did not take.
The other thing you do not care for because of your deep time issue is that we can trace even further back to a kind of "Ark cat" equivalent, called Miacidae, that gave rise over millions of years to the lineages of feline, canine and ursine. All by the same kind of speciation events you already acknowledge from Ark cat but just a whole lot more of them.
So macroevolution is no ploy but the definition of a process. A process with which you already agree: a line of speciation events.
So what is the problem with using the word as classically defined?
You're already inundated with enough stuff. Don't answer. Just consider this rhetorical.
Re: This thread should be about facts not interpretaions
I accept that the EVENT called "speciation" occurs but I do not accept the name "speciation," I simply feel obliged to put up with it because it DOES describe an actual event.
As long as it remains a cat a creationist shouldn't call it "speciation" or "macroevolution." If you have to call it something, call it "subspeciation."
The parent and daughter populations' genomes become so distinct they can longer play well together. Sub-speciation, potato, whichever.
Now that we're done with the vegetables how about goose and gander?
Didn't you just say ...
... it's not scientific to try to define your opponents out of the argument, let alone force your terminology on them ...
and yet here you are.
"Macroevolution" implies that the genome can eventually morph into another kind of genome. Evolutionists believe that happens, creationists don't.
But you already know that since the sub-species' genome is no longer compatible with the parent it has already started to morph around the edges, hasn't it. A couple thousand more generations and that far ending sub-species, now called a Bengal Tiger, has morphed so much it doesn't see Ark cat as a mate so much as it sees a tasty juicy lunch.
I know, allele changes and loss of diversity only. Allele changes and diversity loss so sever that the metabolic pathways are altered to the point of incompatibility. That is a pretty hefty dose of genome morphing right there.
Now on the other side of the Ark cat lineage is that trail of sub-species begetting sub-species out to the sub-species called the Domestic House Cat.
In keeping with the nested hierarchy (an evolution concept that this Ark cat scenario demonstrates quite well) House cat and Bengal tiger are still feline, as in "of the cat kind" but their genomes have morphed a considerable distance from each other, haven't they.
I know you don't like the word for religious reasons, but, House cat on one side and Bengal tiger on the other with very similar and yet considerably different genomes is macro-evolution accomplished with nothing more than a lineage of "sub-species", micro-evolution, centered on and spreading out from your Ark cat.
If you believe that some Ark Cat populated all the separate and wide spread "sub-species" of cat-kind in the world today then you believe in the concept of macro-evolution whether you accept the appellation or not.
And yes, Faith, for Ark Cat's genome to branch out and develop such a variety of disparate cat "sub-species" it morphed a considerable amount indeed.
I have no doubt that this is just the usual case of similarities being mentally transformed into genetic descent, just say it and abracadabra presto changeo it is whatever your magical incantation wants it to be, which is how the ToE works. Just interpret the facts to fit the theory, who needs to prove any of it?
There you go, again, calling generations of very smart people stu*pid for finding and following the facts that you are not smart enough to see sitting right in front of you.
And yet, again, what happened to ...
While paradigm clashes usually do involve some degree of hostility between the views, it's not scientific to try to define your opponents out of the argument, let alone force your terminology on them, and heap ridicule on them and all the rest of it.
You give sanction then turn right around and violate it. That is not appropriate behavior for a lady. Or anyone else for that matter.
I am unable to read that page. It's hard on my eyes from the whiteness and the print is too small. I could probably make it readable but I'd have to have a good reason for doing that, if you could explain that to me. Thanks.
Well, the best reason for doing so is because I am the one who put it up and since I find it interesting then the entire universe must also find it interesting. What more reason does one need?
The table lists each human chromosome, number of genes on each, number of exons/introns and sizes in base pairs for each. The source may be better for your eyes, it is a bit clearer but the same color scheme. Maybe a printout would be best.
Another interesting site I found (yes, interesting to the entire universe, again) is this one. It lists information on each chromosome and if you follow a link on the individual chromosome page you get information on some of the identified genes on that chromosome.
The entire site is quite good. If some message/book/paper gives a reference to some specific gene by name you can look it up here for detailed information on that gene. You can also look at general areas like "Eyes and Vision" and "Immune system" and find identified genes that are known to influence these areas.
A handy reference indeed. OK, so maybe not the entire universe will find this as interesting as I do. Sometimes I can be too easily entertained.