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← Does Evolution Select For Faster Evolvers? Horizontal Gene Transfer Adds To Complexity, Speed Of Evolution

Does Evolution Select For Faster Evolvers? Horizontal Gene Transfer Adds To Complexity, Speed Of Evolution - Comments

padster1976's Avatar Comment 1 by padster1976

My firt post didn't appear.

I asked if this type of evolution would explain the 'cambrian explosion'?

Any thoughts?

See here.... for info!

http://en.wikipedia.org/wiki/Cambrian_explosion

Tue, 30 Jan 2007 07:16:00 UTC | #17799

jonecc's Avatar Comment 2 by jonecc

It's obviously hard to make predictions with a statistical group of one, but when I first saw the figures I was struck by the way that monocellular life seemed to get going virtually as soon as the asteroid bombardment stopped, by the standards of geological time. The jump to truly sophisticated multicellular life then took about 3 billion years, whilst the jump from there to mammals in space took about half a billion.

If this pattern was typical of the galaxy (which I realise is a BIG if), then you would expect life to evolve fairly quickly when conditions suited it, but to often stay "stuck" (from our multicellular viewpoint) at the simple stage. Where it goes multicellular, it's got a good chance of going sentient.

Just a thought.

Tue, 30 Jan 2007 08:24:00 UTC | #17804

HalfaMind's Avatar Comment 3 by HalfaMind

"We know that the majority of the DNA in the genomes of some animal and plant species -- including humans, mice, wheat and corn -- came from HGT insertions,"

Whoa! Can someone help me out here?

1. Is the suggestion here that HGT is the PREVALENT mechanism that generates the genetic diversity selection acts on, or have I missed the point?

2. If so, is that in terms of frequency, impact on the phenome, or what? If HGT is as frequent as it seems to be, it doesn't seem surprising to me that it is much more effective than random mutation - after all, you're more likely to get a result shoving a complete tested subroutine into your program than a random string of ones and zeroes.

3. Is there somewhere where those interested can go to get a good account of HGT and its place alongside genetic drift, mutation and sexual selection as an engine of change? It seems rather significant - could it possibly change our view about how one species apparently gives way to another. Could HGT resurrect (no offence intended!) the corpse of macromutation with a shiny new badge?
Thanks.

Tue, 30 Jan 2007 09:15:00 UTC | #17810

jonecc's Avatar Comment 4 by jonecc

SF, thanks very much. How wonderful that we can just click a button and watch these guys. I shall work my way through this video, and indeed most of the ones listed on the same page.

I do think you ought to trim your tusks, though, before you lose an eye or something.

Tue, 30 Jan 2007 09:17:00 UTC | #17811

A.Lex's Avatar Comment 5 by A.Lex

SF stated that "Apparently multicellular life has appeared several times, as well as eyes, etc, but intelligence only once."
That's not true - intelligence may appear one more time among the Fundies sub-species.

Tue, 30 Jan 2007 09:23:00 UTC | #17812

Lionel A's Avatar Comment 6 by Lionel A

Just so happens that I have been reading about this in Dennett's 'Darwin's Dangerous Idea', p.p. 141-145. Yes it can happen and Dennet cited an example where a species of drosophila had another species DNA inserted by an unwitting mite.

This book is now rather 'long in the tooth' and I wondered as I read as to what other discoveries in this area have been made in the interim.

Tue, 30 Jan 2007 09:28:00 UTC | #17813

Manfred's Avatar Comment 7 by Manfred

This is a quote from the nature esay that SF linked to (see above):

"Nowhere are the implications of collective phenomena, mediated by HGT, so pervasive and important as in evolution. A computer scientist might term the cell's translational apparatus (used to convert genetic information to proteins) an 'operating system', by which all innovation is communicated and realized. The fundamental role of translation, represented in particular by the genetic code, is shown by the clearly documented optimization of the code. Its special role in any form of life leads to the striking prediction that early life evolved in a lamarckian way, with vertical descent marginalized by the more powerful early forms of HGT.

Refinement through the horizontal sharing of genetic innovations would have triggered an explosion of genetic novelty, until the level of complexity required a transition to the current era of vertical evolution. Thus, we regard as regrettable the conventional concatenation of Darwin's name with evolution, because other modalities must also be considered."

If the process was Lamarckian, it suggests that there was not a single common ancestor from which all life has descended. This would have profound effects on our understanding of evolution. What would happen to the tree of life picture? Is this Lamarckian process still going on? I always thought that is not so, and the Darwinian picture is the one giving the correct explanations. Is there any point where vertical(Darwinian) evolution has emerged as opposed to or along with the horizontal gene swap? And how do they compare?

It would be interesting (and helpful) to know what Richard Dawkins thinks about this.

Tue, 30 Jan 2007 09:51:00 UTC | #17816

AdrianB's Avatar Comment 8 by AdrianB

I have to say that as somebody who just takes a casual interest in the science on evolution, this is one of the most interesting concepts I have read about.

In fact, when one steps back and thinks about it for a few moments, the idea seems blindingly obvious.

I look forward to RD's comments.

Tue, 30 Jan 2007 10:16:00 UTC | #17820

Manfred's Avatar Comment 9 by Manfred

Ok, for anyone who is interested, I found this article in "Proceedings of the National Academy of Sciences" which gives a critical view of the HGT (as long as its effects on evolution goes):

http://www.pnas.org/cgi/content/abstract/100/17/9658

(I am not sure you can get to the full article without subscription though).

Tue, 30 Jan 2007 10:50:00 UTC | #17826

LookToWindward's Avatar Comment 10 by LookToWindward

I thought it was just because the majority of our DNA was responsible for the intricate machinery within our cells, therefore you'd expect single-celled life to take up the majority of evolutionary history?

Tue, 30 Jan 2007 10:56:00 UTC | #17827

C Quil's Avatar Comment 11 by C Quil

I'm not sure I like who's funding the research.

"The research is supported by the Defense Advanced Research Projects Agency."

Tue, 30 Jan 2007 10:57:00 UTC | #17828

Sancus's Avatar Comment 12 by Sancus

http://en.wikipedia.org/wiki/Accelerating_change

Accelerating change has to have some mathematical mechanism. If this new model overstates HGT's influence on evolution, then it just means there's more left to be discovered.

Tue, 30 Jan 2007 13:41:00 UTC | #17853

3rdGenAth's Avatar Comment 13 by 3rdGenAth

To anyone interested in some detailed science that covers this area, I would strongly recommend "Power, Sex, Suicide: Mitochondria and the Meaning of Life" by Nick Lane:
http://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning/dp/0192804812

Author's homepage:
http://pages.britishlibrary.net/nick.lane/

One of the main components of the book is the origin of eukaryotic cells:
http://en.wikipedia.org/wiki/Eukaryote#Origin_and_evolution

In the early part of the book, he argues that bacteria seem to have never been able to evolve into eukaryotic-type cells despite having about 4 billion years available. He also goes into a deep analysis why - how bacteria compete and evolve is significantly different to eukaryotic cells (which are the basis of all animals).

There's lots of other interesting stuff covered such as why genders exist - and particular why just 2 (most of the time). There's also some very facinating stuff on aging.

Tue, 30 Jan 2007 16:10:00 UTC | #17874

Aussie's Avatar Comment 14 by Aussie

A much simpler and more elegant explanation is provided by an ingenious theory known as Intelligent Design. Seems like nobody here has even heard of it.

Tue, 30 Jan 2007 21:41:00 UTC | #17915

Billy Sands's Avatar Comment 15 by Billy Sands

This phenomenon has been known for some time, but is ignored by the IDiots. Their need to literally see an "increase of information" and the evolution of new taxa is tied to their fundamental lack of understanding as to how evolution works. Shame they are not so critical of biblical myths


Padster
It's possible. I think Sex dramatically facilitated the speed of evolution too. It causes more variations that can be selected simultaneously

Wed, 31 Jan 2007 03:28:00 UTC | #17956

jeff_n's Avatar Comment 16 by jeff_n

Aussie says:

A much simpler and more elegant explanation is provided by an ingenious theory known as Intelligent Design. Seems like nobody here has even heard of it.

Considering such design anomalies as Evangelical Christians, tree kangaroos, and the bizarre insistence on building everything with folded-up chain molecules, the "Design by Committee" hypothesis looks promising.

Wed, 31 Jan 2007 12:14:00 UTC | #18057

Richard Morgan's Avatar Comment 17 by Richard Morgan

Brilliant idea! HGT would certainly explain why one of my seven children bears a striking resemblance to our postman!

Also this can become the new chat-up line in sleazy night clubs: "Hey sweety, how about going back to my place for a bit of horizontal gene transfer?"

Waadya think, guys?

Fri, 02 Feb 2007 00:48:00 UTC | #18294