[Kosh]

http://science.slashdot.org/science/08/01/18/1943255.shtml

"When the researchers measured changes in 40 defined characteristics of the nematodes' sexual organs (including cell division patterns and the formation of specific cells), they found that most were uniform in direction, with the main mechanism for the development favoring a natural selection of successful traits, the researchers said."

Who wants to go first?

[Ford Prefect]

Well, it's about time someone provided some evidence for this "evolution."

[Mobius]

Good, good...more proof!

And what about:

Vatican has widely accepted evolution and the possible existance of aliens so the only creationists left are mad fanatics living in the US? We could care less about their opinions. They should have their own Church, too.

[Bobboau]

wait a second, did anyone read that, it sounds like they are saying mutation is not random... I'm not sure if that's what it was saying or if it was just reconfirming again natural selection, but it sounded like it was saying that mutations (not there expression across generations) have directed trends.

[Kosh]

wait a second, did anyone read that, it sounds like they are saying mutation is not random... I'm not sure if that's what it was saying or if it was just reconfirming again natural selection, but it sounded like it was saying that mutations (not there expression across generations) have directed trends.

, they found that most were uniform in direction, with the main mechanism for the development favoring a natural selection of successful traits, the researchers said.

Looks like reconfirming natural selection

[Ford Prefect]

Yeah, I don't think they're saying the trends are directed, just that evolution is deterministic, meaning that a given occurrence emerges causally from previous occurrences. I didn't realize this was still a debate; it doesn't sound particularly radical.

[Bobboau]

saying it's deterministic implies you can predict what will happen precisely, which to a degree is true. if an animal feeds from a tree and the tree gets taller, then the animal will have to get taller or starve, but it can not tell you if it will get long legs or a long neck, hell the animal could learn to climb and actually get shorter.

[Ford Prefect]

The term "determinism" only implies you could theoretically predict precisely what will happen if you had every possible piece of information, which no one ever has, in any situation.

[Bobboau]

in which case everything in the universe is deterministic.

[Ford Prefect]

Precisely. That's why the link strikes me as odd, but then again there isn't much of it.

[MP-Ryan]

I'd like to see a journal article rather than such a brief summary.

Genetic mutation is not deterministic; it is random.  Mutation visible in the population at any given point in time will appear deterministic, however.

[Kosh]

I'd like to see a journal article rather than such a brief summary.

Genetic mutation is not deterministic; it is random.  Mutation visible in the population at any given point in time will appear deterministic, however.

Mutation is random, but natural selection is not, which is what this study was about.

[Ford Prefect]

It actually seems like poor word choice, seeing as "determinism" is a concept that still has one foot planted firmly in philosophy. Whoever wrote that summary opened up a whole can of worms that I doubt they meant to suggest.

[jdjtcagle]

Mutation is random, but natural selection is not, which is what this study was about.

Exacly, but that's not what that thread implies... So they bred worms and a majority started to developed certain advantages changes to their environment?  What changes to what environment.  Also isn't there also things called environmental genes that only "kick in" when the organism is under certain environments.  Testing was done on twins that grew up in different environments.

Something to think about.

Yes, I do 'obviously' believe in God but also believe in not judging others for their belief in whatever, which in turn "not very Christian" I'm NOT here to get into any religious debate. Just always like to keep my ears open and learn

[MP-Ryan]

Mutation is random, but natural selection is not, which is what this study was about.

That's not what I got from the summary, but then again that's a VERY badly written summary (which is why I want to see the journal article, if they'd bothered to actually put down the names of the researchers *sigh*).

If the study honestly concluded that "natural selection is not random," then I'd like to award the authors the Captain Obvious Prize for 2008.  That's the fundamental premise of natural selection, hence the "selection" part.  If you read On the Origin of Species, Darwin himself states that natural selection isn't random.  It can't be random for eveolutionary theory to make any sense.

Again... bad summary.  I suspect this isn't what the researchers found at all.  If it is, they need to be properly ridiculed for it.

So they bred worms and a majority started to developed certain advantages changes to their environment?  What changes to what environment.  Also isn't there also things called environmental genes that only "kick in" when the organism is under certain environments.  Testing was done on twins that grew up in different environments.

I'm putting this as politely as I can.... pleeeeeaaaase don't talk about genetics if you don't actually know what you're talking about.  It'll confuse people.

I don't know what you're getting at with your first two sentences, but your third is, I suspect, referring to environmental triggers?  Gene cascades are frequently activated by external stimuli, ranging from touch, to temperature, to pressure, to salinity, etc etc ad nauseum.  That in itself has little to do with natural selection wherein an organism with mutations that promote survival in certain conditions will reproduce successfully while those without will die.

[MP-Ryan]

I tracked down the article.  Here's the tidbits I can legally reproduce:

Summary
Background: A surprising amount of developmental variation has been observed for otherwise highly conserved features, a phenomenon known as developmental system drift. Either stochastic processes (e.g., drift and absence of selection-independent constraints) or deterministic processes (e.g., selection or constraints) could be the predominate mechanism for the evolution of such variation. We tested whether evolutionary patterns of change were unbiased or biased, as predicted by the stochastic or deterministic hypotheses, respectively. As a model, we used the nematode vulva, a highly conserved, essential organ, the development of which has been intensively studied in the model systems Caenorhabditis elegans and Pristionchus pacificus.

Results: For 51 rhabditid species, we analyzed more than 40 characteristics of vulva development, including cell fates, fate induction, cell competence, division patterns, morphogenesis, and related aspects of gonad development. We then defined individual characters and plotted their evolution on a phylogeny inferred for 65 species from three nuclear gene sequences. This taxon-dense phylogeny provides for the first time a highly resolved picture of rhabditid evolution and allows the reconstruction of the number and directionality of changes in the vulva development characters. We found an astonishing amount of variation and an even larger number of evolutionary changes, suggesting a high degree of homoplasy (convergences and reversals). Surprisingly, only two characters showed unbiased evolution. Evolution of all other characters was biased.

Conclusions: We propose that developmental evolution is primarily governed by selection and/or selection- independent constraints, not stochastic processes such as drift in unconstrained phenotypic space.

And I conclude that the Slashdot and ScienceDirect authors need to learn how to read scientific papers, because their summary is about as relevant to this paper as pink elephants.

This paper is discussing developmental evolution, which is not the same type of evolution that non-biologists are familiar with.

Interesting paper though, I take back the ridicule =)

[jdjtcagle]

Mutation is random, but natural selection is not, which is what this study was about.

So they bred worms and a majority started to developed certain advantages changes to their environment?  What changes to what environment.  Also isn't there also things called environmental genes that only "kick in" when the organism is under certain environments.  Testing was done on twins that grew up in different environments.

I'm putting this as politely as I can.... pleeeeeaaaase don't talk about genetics if you don't actually know what you're talking about.  It'll confuse people.

I don't know what you're getting at with your first two sentences, but your third is, I suspect, referring to environmental triggers?  Gene cascades are frequently activated by external stimuli, ranging from touch, to temperature, to pressure, to salinity, etc etc ad nauseum.  That in itself has little to do with natural selection wherein an organism with mutations that promote survival in certain conditions will reproduce successfully while those without will die.

Duely noted, I'm not saying I know anything... In fact I was attempting to ask a question.  btw, being misunderstood doesn't automatically put me in the ignorant category, again I was asking how they got this info. I ASK because I don't understand.

I'm not being biased so please before you quote me know I'm listening not attacking.

YES I was talking about environment triggers, thank you.

[jdjtcagle]

words in there are brutal for my puny mind... 

I'm having difficulty understanding the part about how all but 2 showed "biased" changes... 

We propose that developmental evolution is primarily governed by selection and/or selection- independent constraints, not stochastic processes such as drift in unconstrained phenotypic space.

Someone please define this in laymen terms... thank you

[G0atmaster]

It's still quite a leap from simultaneously developing the dozen or so chemical processes required to make blood clot, all in time to keep early lifeforms from bleeding to death.

[redsniper]

early lifeforms didn't have blood.