Nerdfighters


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It allows for other possibilities, and means that abiogenesis is no longer the only game in town. Given the fact that we can now no longer trace our ancestry nessecarily to a single cell, who is to say that we began with single cells at all?

Explain what you mean by 'abiogenesis is not the only game in town anymore'? Abiogenesis is the name for whatever mechanism that takes inorganic life and makes it living, whether it's religious genesis or natural processes. As a science it is experimental and looks at it from many angles, but does not expect it to be one single flash bang occurrence. 

I agree that more than one origin opens up more possibilities in terms of evolution, but I am curious what kind of possibilities you are talking about, because I get this feeling your not talking about the same.

I still think it HGT under no circumstance circumvents the need for simple single cell origins, or at most at least no more than clusters of single cells having dynamic relations with each other. Never the less, abiogenesis leads up to one operational cell, or other non-living organics such as viruses. What that cell does afterwards, aka dies, splits, absorbs/hook up with other cells, does completely depend on what kind of cell/life was created and what surrounds it.

Explain what you mean by 'abiogenesis is not the only game in town anymore'? Abiogenesis is the name for whatever mechanism that takes inorganic life and makes it living, whether it's religious genesis or natural processes. As a science it is experimental and looks at it from many angles, but does not expect it to be one single flash bang occurrence.

HGT means that we don't have to have started with a single simple lifeform and branched out from there. For all we know, we could have started with a more complex life form. How did that happen? I don't know, but because we have genes moving horizontally and vertically, we have a situation which means we can't trace our ancestry the way we thought.

I agree that more than one origin opens up more possibilities in terms of evolution, but I am curious what kind of possibilities you are talking about, because I get this feeling your not talking about the same.

I'm saying that it's possible that we started off with a complex life form. Since we can't trace ancestry as surely as we could, we now have issues with saying "this branched off from this" with the same kind of authority, at least as far is genetics is concerned.

I still think it HGT under no circumstance circumvents the need for simple single cell origins, or at most at least no more than clusters of single cells having dynamic relations with each other

Of course it does. You can't now say "This organism proceeded this other organism which passed down its DNA" because we don't know for sure the DNA got there as a result of things passing them down.

For all we know, we could have started with a more complex life form.

I can see no reason how we could suppose that, and based on what you have presented so far, I don't see how you can suppose it either.

I'm saying that it's possible that we started off with a complex life form.

All evidence indicates that multicellular life is between 600-700 million years old, while life it self is more than 3.5 billion years old. That pretty much settles it I think.

You can't now say "This organism proceeded this other organism which passed down its DNA" because we don't know for sure the DNA got there as a result of things passing them down.

Apart from the rare cases of possible cross-speciation among not so closely related species, you overestimate the gravity of HGT. You see, in vertical transfers, the entire DNA is normally passed over from one generation to the next, while with HGT only a select few genes usually are. These foreign genes will in  larger organisms again only alter a small percentage of their combined cells. This is why HGT is more common in plants, because most plants are not dependent on sexual reproduction alone in order to spread. Of course these bits and pieces of horizontally accumulated genes have over time contributed huge amounts of discrepancies to the formerly expected tree, and that is what we are discovering. We will still be able to verify kinship between species by following the trail of vertical transfers, which is still possible, it's just harder. And the further apart you go, the harder it gets. It might be impossible for microbes, but not for plants and animals.

Also your point of irreducible complexity also falls flat due to the principle co-evolution, and to the fact that genes usually possess more than one property.

If you take out one or more genes from an organism so that you alter its shape and capabilities, it will still operate, just differently. 

Of course for complex creatures, such as a hummingbird it is a bit different, but you have to consider the fact that the flower has changed too. If you remove the gene(s) that determines the shape of the birds beak, then of course the bird can not eat and it dies, because the environment on which it is dependent has changed relative to how it was last time the beak were of that shape. You'd have to reverse engineer to flower it is dependent on as well. There may be other, less obvious changes to the bird and plant too, such as changes the bird's digestive system, which would make this very hard to do. Reverse engineered animals of extreme speciality will therefor not necessarily be backwards compatible with present day environments.

You see, in vertical transfers, the entire DNA is normally passed over from one generation to the next, while with HGT only a select few genes usually are.

Except my sources point out that some very large percentages of human DNA could be horizontally transferred. 40-50%. I guess you can drop the "a select few genes" line. This is a big deal.

All evidence indicates that multicellular life is between 600-700 million years old, while life it self is more than 3.5 billion years old. That pretty much settles it I think.

Evidence based on a model that uses vertical gene transference as its primary basis. If gene transference moves differently, we could see something else.

I can see no reason how we could suppose that, and based on what you have presented so far, I don't see how you can suppose it either.

Because we've supposed up until now that the reason that X has Y's genes is that Y came before it. Maybe it didn't.

Im not sure but I think you might have a skewed view of HGT....dont quote me on this but having known nothing about the subject Ive done some reading...For starters it doesn't disprove evolution....the changes in environment forcing creatures to adapt is still sound what is does mean is that speciation is slightly more complex than was originally assumed. Which doesn't surprise me in modern science if you see a well ordered system there is genrally more going on there than we know or so it seems. What HGT does show is that all life is one..the ability to undergo HGT indicates all life has a common ancestry otherwise the mechanism for such transfer wouldn't be possible. Currently observable HGT has only been seen on the scale of micro organisms rather than more complex life (I cannot pass my genes onto you without some form of hanky panky) so it might be the case that HGT was the starting point of gene transferal before more complex methods took hold. Still as it turns out life is more complex than we give it credit for...also we share a great deal of DNA data with nearly all life any how...id like to see the human specific genes which are transferable via HGT seeing that between humans we have a 0.01% change within our individual data.

For starters it doesn't disprove evolution

Go ahead and try to quote me saying it did.

the changes in environment forcing creatures to adapt is still sound what is does mean is that speciation is slightly more complex than was originally assumed.

I agree, and more to the point, I never said that I didn't. So maybe you want to stop making arguments against issues that I didn't raise.

Currently observable HGT has only been seen on the scale of micro organisms rather than more complex life (I cannot pass my genes onto you without some form of hanky panky)

But there is plenty of evidence to support the idea that 40-50% of human DNA is here via HGT

Go ahead and try to quote me saying it did.


Umm considering the nature of the discussion? You brought up HGT so I must admit I assumed (making an ass out of umed) that it was relevant to the debate...why bring it up otherwise?

whats more I was just putting out general points as to how HGT and evolution work together not an attack on your beliefs...

But there is plenty of evidence to support the idea that 40-50% of human DNA is here via HGT


Huh? please can you clarify do you mean 50% of the DNA found in humans or 50% of DNA only found in humans...as its an important point to be clear on.

also like 3 pages ago didn't you agree that evolution if not abiogenesis happened? Thus settling the original topic for discussion......what are we arguing about now?

Exactly, you do argue as if you find the theory of evolution highly compromised due to the issues that you raise and from the way that you phrase them. You simply have to excuse us misinterpreting you and try to elaborate instead of pouting, because all I get is misconceptions on your part.

It can be a tad distracting from the main thrust of an argument if you start side arguments which have no basis on your opinion

Except my sources point out that some very large percentages of human DNA could be horizontally transferred. 40-50%. I guess you can drop the "a select few genes" line. This is a big deal.

Point is that those 40-50% didn't happen all at once. They are accumulated themselves through vertical evolution, and the majority of which didn't even happen while we were humans. That means that the majority of those discrepancies will have been passed down vertically though ordinary reproduction. That explains why the discrepancies increases the further away from kinship you get, and how they turn up in odd places. HGT are per definition unevenly distributed. Where they might prove useful for some species (or individuals among them) and thus spread vertically, they might prove disastrous for others. 

Evidence based on a model that uses vertical gene transference as its primary basis. If gene transference moves differently, we could see something else.

No, I think that is mostly backed by fossil evidence, but of course I am always ready to eat my words. I think I've proven that on an occasion or two.

Point is that those 40-50% didn't happen all at once.

Did you see me claiming that it did? My point was that you can't write of HGT to a little outlying phenomenon. It's a big deal, and it raises lots of questions.

No, I think that is mostly backed by fossil evidence, but of course I am always ready to eat my words. I think I've proven that on an occasion or two.

The same fossil record that has a single tree covering eras that are supposed to be seperated by several million years.

Here's the bottom line of my argument. Up until recently, all we had with evolution as the origin story was observation. It was an interpretation of how the various species changed and grew. Then, we had genetics, which showed that actually, species shared so much DNA, that they did evolve into each other, but now we are seeing that actually, the DNA is shared via other means than just reproduction. Therefore, the question of whether we do in fact have a single lineage is now more up for debate, and maybe the model of evolution we know and love is in fact flawed, and if that's flawed, maybe the idea that humans and chimpanzees share a common ancestor is also flawed. The claim that DNA is brilliant evidence for the classical model of evolution is now flawed.

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