A genetic trigger for the Cambrian explosion unravelled?

LeftofLarry
RRS local affiliateScientist
LeftofLarry's picture
Posts: 1199
Joined: 2006-02-12
User is offlineOffline
A genetic trigger for the Cambrian explosion unravelled?

A genetic trigger for the Cambrian explosion unravelled?

http://www.sciencecentric.com/news/07090303.htm 

Science Centric
— 3 September 2007 | 11:34 GMT

A team of scientists led by young Croatian evolutionary geneticist Tomislav Domazet-Loso from Ruder Boskovic Institute (RBI) in Zagreb, Croatia, developed a novel methodological approach in evolutionary studies. Using the method they named ‘genomic phylostratigraphy,’ its authors shed new and unexpected light on some of the long standing macroevolutionary issues, which have been puzzling evolutionary biologists since Darwin.

The only direct method of research in evolutionary history involves analysing the fossil remains of once living organisms, excavated in various localities throughout of the world.

However, that approach often cannot provide the full evolutionary pathway of some species, as it requires uncovering of many fossils from various stages of its evolutionary history. As the fossil record is imperfect, the evolution research fundamentally hinges on luck factor in discovering the adequate palaeontological sites. However, the RBI team proposed a novel and interesting approach to bypass this obstacle. Namely, they suggested that the genome of every extant species carries the ‘snapshots’ of evolutionary epochs that species went trough. What’s even more important, they also developed the method which enables evolution researchers to readily convert those individual ‘snapshots’ into the full-length ‘evolutionary movie’ of a species.

Applying their new methodology on the fruit fly genomic data they tackled some of the most intriguing evolutionary puzzles — some of which distressed even Darwin himself. First, they demonstrated that parts of the living organism exposed to the environment — so called ‘ectoderm’ — are more prone to evolutionary changes. Further, they explained the evolutionary origin of the ‘germ layers,’ the primary tissue forms that form during the first days after the conception of a new animal, and from which subsequently all other tissues are developed. Finally, they discovered the potential genetic trigger for the ‘Cambrian explosion,’ a major global evolutionary event on the planet, when some 540 million years ago almost all animal forms known today suddenly ‘appeared.’

The first public lecture on these findings will be given by Dr Domazet-Loso on 4 September at 5. ISABS Conference in Forensic Genetics and Molecular Anthropology, held in Split, Croatia. The groundbreaking paper fully presenting the theory of genomic phylostratigraphy will appear in the November issue of ‘Trends in genetics,’ the most established monthly journal in Genetics.

Atheist Books, purchases on Amazon support the Rational Response Squad server which houses Celebrity Atheists.


deludedgod
Rational VIP!ScientistDeluded God
deludedgod's picture
Posts: 3221
Joined: 2007-01-28
User is offlineOffline
This is interesting stuff.

This is interesting stuff. I personally always held that the genetic trigger for the Cambrian explosion was the development of Hox Genes. The creation of Homeoboxes based on animals  which all adopt the "tube structure" allows for rapid phylogenic diversification of multicellular animal Eukaryota. The mutation changes which govern Hox genes, then (for example the Position Vateriagation Effect, which is the alternation of condensed heterochromatin and euchromatin in the nucleosome structure of Eukaryotic genetic sequestering) leads to novel new patterns in the embryonic development of the organism in question. Also, the shifts in Hox genes means that all animals are based on the same basic structure, which is the tube, which is essentially universal and throughout animal evolution the change, elongations and additions to the tube are explained through the Hox. The Hox is useful because when IDiots point to complex biomolecular or anatomical structure, Hox Flow mechanisms are used to precisely pinpoint the evolutionary mechanisms which cause these structures to develop. The discovery of Hox genes has led to a shift in previous thinking on evolutionary biology, instead of millions of small mutations creating complex biological structures, we have a relatively small number of major Hox tweaks coupled with much noise mutation. From this was born a new arm of molecular biology: Ev-devo.

The hox genes explain why animal evolution occurs much faster than bacterial. When I say faster, I don't mean in terms of years, I mean in terms of generations. 

"Physical reality” isn’t some arbitrary demarcation. It is defined in terms of what we can systematically investigate, directly or not, by means of our senses. It is preposterous to assert that the process of systematic scientific reasoning arbitrarily excludes “non-physical explanations” because the very notion of “non-physical explanation” is contradictory.

-Me

Books about atheism


LeftofLarry
RRS local affiliateScientist
LeftofLarry's picture
Posts: 1199
Joined: 2006-02-12
User is offlineOffline
Oh I agree.. absolutely. 

Oh I agree.. absolutely.  I think the authors of the article are tyring to show, inherently, not just out of speculation what caused the cambrian explosion, which for sure was due to HOX genes.

 

Here check this out..for anyone here interested..this video is a good video.  

 

http://www.pbs.org/wgbh/evolution/library/03/4/l_034_04.html 

 

Last night Mike was debating the Mr. Riddles from Answers in Genesis.  The flawed argument Mr. Riddles was giving was that evolution is not possible due to the fact that mutations are usually bad or null.  Clearly he showed extreme ignorance to the science of evolutionary biology.  They completely ignore new evidence and latch on to simplistic arguments. 

 Evo-devo...check out Sean Carroll book The Making of the Fittest, DNA and the ultimate forensic record of evolution.

Atheist Books, purchases on Amazon support the Rational Response Squad server which houses Celebrity Atheists.


deludedgod
Rational VIP!ScientistDeluded God
deludedgod's picture
Posts: 3221
Joined: 2007-01-28
User is offlineOffline
The video link doesn't

The video link doesn't work. The reason for that, you might notice, is that there is a little empty space on the very end of the URL, the underline goes just past the "l", that makes the URL malinformed. Here, I'll show you how to fix it:

 http://www.pbs.org/wgbh/evolution/library/03/4/l_034_04.html 

It should loook like this:

http://www.pbs.org/wgbh/evolution/library/03/4/l_034_04.html

Quote:

early he showed extreme ignorance to the science of evolutionary biology.  They completely ignore new evidence and latch on to simplistic arguments.

Of course they do. If they didn't, they wouldn't be creationists in the first place. Although crushing creationist arguments is an easy chore, I sometimes feel that, for all that I am imparting, this:

 

Might be a better use of my time

Quote:

 Evo-devo...check out Sean Carroll book The Making of the Fittest, DNA and the ultimate forensic record of evolution.

Already picked it up.

PZ write anything on it? 

 

"Physical reality” isn’t some arbitrary demarcation. It is defined in terms of what we can systematically investigate, directly or not, by means of our senses. It is preposterous to assert that the process of systematic scientific reasoning arbitrarily excludes “non-physical explanations” because the very notion of “non-physical explanation” is contradictory.

-Me

Books about atheism


LeftofLarry
RRS local affiliateScientist
LeftofLarry's picture
Posts: 1199
Joined: 2006-02-12
User is offlineOffline
ah..thanks for fixing the

ah..thanks for fixing the link.  and I do agree with you that trying to squeeze blood out of a rock is time better spent than debating creationsists. 

 

and who's PZ?

Smiling 

Atheist Books, purchases on Amazon support the Rational Response Squad server which houses Celebrity Atheists.


BGH
BGH's picture
Posts: 2772
Joined: 2006-09-28
User is offlineOffline
LeftofLarry wrote: and

LeftofLarry wrote:

and who's PZ?

Smiling

PZ Myers of the Pharyngula Blog, it is a great science/religion related blog: http://scienceblogs.com/pharyngula/

 

PZ Myers is a biologist and associate professor at the University of Minnesota, Morris

 


todangst
atheistRational VIP!
todangst's picture
Posts: 2811
Joined: 2006-03-10
User is offlineOffline
deludedgod wrote:   The

deludedgod wrote:

 

The hox genes explain why animal evolution occurs much faster than bacterial. When I say faster, I don't mean in terms of years, I mean in terms of generations.

Nice clarification. Thanks.  

Those who know the good, do the good. - Socrates

Books on atheism.