Evolution at warp speed: Hatcheries change salmon genetics after a single generation

Dec 19, 2011
Steelhead trout return to spawn. (Photo by John McMillan, courtesy of Oregon State University)

The impact of hatcheries on salmon is so profound that in just one generation traits are selected that allow fish to survive and prosper in the hatchery environment, at the cost of their ability to thrive and reproduce in a wild environment.

These findings, published this week in , show a speed of evolution and natural selection that surprised researchers.

They confirmed that a primary impact of hatcheries is a change in genetics, as opposed to a temporary environmental effect.

"We've known for some time that hatchery-born fish are less successful at survival and reproduction in the wild," said Michael Blouin, a professor of zoology at Oregon State University. "However, until now, it wasn't clear why. What this study shows is that intense evolutionary pressures in the hatchery rapidly select for fish that excel there, at the expense of their reproductive success in the wild."

Hatcheries are efficient at producing fish for harvest, the researchers said, but this and other studies continue to raise concerns about the genetic impacts that hatchery fish may have when they interbreed with wild salmon, and whether or not they will help runs to recover.

These findings were based on a 19-year of steelhead in Oregon's Hood River. It examined why hatchery fish struggle to reproduce in wild river conditions, a fact that has been made clear in previous research. Some of the possible causes explored were environmental effects of captive rearing, among close relatives, and unintentional "domestication selection," or the ability of some fish to adapt to the unique hatchery environment.

The study confirmed that domestication selection was at work.

When thousands of smolts are born in the artificial environment of a hatchery, those that survive best are the ones that can deal, for whatever reason, with hatchery conditions. But the same traits that help them in the hatchery backfire when they return to a wild river, where their ability to produce surviving offspring is much reduced.

"We expected to see some of these changes after multiple generations," said Mark Christie, an OSU post-doctoral research associate and lead author on the study. "To see these changes happen in a single generation was amazing. Evolutionary change doesn't always take thousands of years."

It's not clear exactly what traits are being selected for among the thousands of smolts born in hatcheries, the scientists said, but one of the leading candidates is the ability to tolerate extreme crowding. If research can determine exactly what aspect of hatchery operations is selecting for fish with less fitness in the wild, it could be possible to make changes that would help address the problem, they said.

Historically, hatchery managers preferred to use fish born in hatcheries as brood stock to create future generations, because whatever trait they had that allowed them to succeed in the hatchery helped produce thousands of apparently healthy young salmon. But they later found that those same fish were released they had a survival and that was far lower than those born in the wild.

Billions of captive-reared salmon are intentionally released into the wild each year in order to increase fishery yields and bolster declining populations. The steelhead studied in this research are, in fact, listed as threatened under the Endangered Species Act, and part of their recovery plan includes supplementation with fish.

"It remains to be seen whether results from this one study on steelhead generalize to other hatcheries or salmon species," Blouin said.

"Nevertheless, this shows that hatcheries can produce fish that are genetically different from wild fish, and that it can happen extraordinarily fast," he said. "The challenge now is to identify the traits under selection to see if we can slow that rate of domestication."

Explore further: Physics determined ammonite shell shape

Related Stories

Salmonid hatcheries cause 'stunning' loss of reproduction

Oct 04, 2007

The rearing of steelhead trout in hatcheries causes a dramatic and unexpectedly fast drop in their ability to reproduce in the wild, a new Oregon State University study shows, and raises serious questions about the wisdom ...

Hatchery fish may hurt efforts to sustain wild salmon runs

Jun 10, 2009

Steelhead trout that are originally bred in hatcheries are so genetically impaired that, even if they survive and reproduce in the wild, their offspring will also be significantly less successful at reproducing, according ...

How to Grow a Bigger Brain

Mar 06, 2006

Hatchery-reared steelhead trout show increased growth of some parts of the brain when small stones are scattered on the bottom of their tank, according to a new study by researchers at UC Davis. The brains ...

Hatchery-raised salmon too crowded

Dec 23, 2009

Every year, large amounts of hatchery-raised young salmonids are released into Swedish rivers and streams to compensate for losses in natural production. Butthese fish generally survive poorly in the wild. ...

Recommended for you

Scientists see how plants optimize their repair

2 hours ago

Researchers led by a Washington State University biologist have found the optimal mechanism by which plants heal the botanical equivalent of a bad sunburn. Their work, published in the Proceedings of the Na ...

User comments : 100

Adjust slider to filter visible comments by rank

Display comments: newest first

Shifty0x88
2.1 / 5 (7) Dec 19, 2011
All so that Steelhead trout can end up on the dinner plate..... what a shame....
dogbert
1.2 / 5 (20) Dec 19, 2011
When you subject a population to extreme selection pressures, it is hardly surprising that you observe selection.

That is not evolution, that is just selection.
liutenantdan
4.6 / 5 (18) Dec 19, 2011
When you subject a population to extreme selection pressures, it is hardly surprising that you observe selection.

That is not evolution, that is just selection.


What?? That is exactly what evolution is. Evolution is any change across successive generations of biological populations.
aroc91
3.3 / 5 (15) Dec 19, 2011
My name's dogbert and I don't know what evolution is!


Derp
Aaryn_Valencia
5 / 5 (1) Dec 19, 2011
most likely its due to how the fish are spawned. most hatcheries select the largest male and female and only cross the two .... where as in the wild several males will fertilize the eggs of a single female... this is especially true with salmon... and don't knock Jacks.. cause in many drainages they have been shown to fertilize 40% or more of the eggs laid...
dogbert
1.7 / 5 (19) Dec 19, 2011
aroc91,
You don't seem to know who you are and you don't seem to know that evolution is theorized to result from selection -- it is not the selection process.

And putting your comment in quotes to imply I said it is dishonest.
aroc91
3.8 / 5 (17) Dec 19, 2011
aroc91,
You don't seem to know who you are and you don't seem to know that evolution is theorized to result from selection -- it is not the selection process.

And putting your comment in quotes to imply I said it is dishonest.


It's not dishonest if it's true and either way, I don't give a rat's ass.

Evolution is a change in a population over time. You're clearly misguided, thinking the process by which it happens has any bearing on whether or not it's evolution. You need to look up the definitions of selection and evolution. The change brought upon by selection is evolution, by definition.

Also, in this case, there is no "theorized." We can watch it happen. It is fact. The differential selection changes gene frequencies in the population. We can track these genes and their frequencies.
dogbert
1.6 / 5 (21) Dec 19, 2011
You can watch selection. Humans have selected for traits for all of our history in both plants and animals. That is not evolution. It is a common error to confuse selection with evolution.
aroc91
3.5 / 5 (11) Dec 19, 2011
...

And that selection has resulted in evolution...

I feel like I'm being trolled.

Read and comprehend this, please. Evolution- change in a population over time. CHANGE IN A POPULATION OVER TIME.

THIS IS THE DEFINITION. THIS IS NOT DISPUTABLE.

FrankHerbert
1.2 / 5 (55) Dec 19, 2011
You can watch selection. Humans have selected for traits for all of our history in both plants and animals. That is not evolution. It is a common error to confuse selection with evolution.


It's a common rhetorical tactic among creationists to conflate the two terms so they can say they support evolution (thus avoiding criticism) while not really buying into it. That is dishonest, though for many probably not intentional.

For dogbert, I believe it is intentional since he so diligently avoids answering the actual question. He does this on any controversial topic.
signoftimes
3.3 / 5 (4) Dec 20, 2011
With that logic, one year in a river changes hatchery salmon. So we have nothing to worry about.
n0ns3ns0r
3.7 / 5 (9) Dec 20, 2011
Religious fundamentalists are taught to go around the intellect by being purposely obtuse. It's like arguing with a three year old.

Yes.
No.
Yes.
No.
Yes.
No.
No!
Yes!

Just trick them like you would a child.
210
1 / 5 (6) Dec 20, 2011
When you subject a population to extreme selection pressures, it is hardly surprising that you observe selection.
That is not evolution, that is just selection.

Dogbert, historically, evolution has been chained/shackled to TIME. Your argument is not entirely without merit! Especially since you amply your statement by indicating "extreme selection pressures" Recommendation: Advance your argument and do so in a manner that is hermeneutically correct for the discipline of evolution. You have raised a valid point/question! Just how much 'time' and how much 'pressure' can humanity exert in a given time, that is biologically equivalent to the process we know as evolution?!? Is short term economically motivated 'selection' going to create the historical norm of Long Term Change that we call evolution? If yes, that is, within a single NON-breeding period - no exchange of DNA has occurred- what were the triggers and where did they have the greatest effect? You may B on 2 something!
word
MarkyMark
3.7 / 5 (3) Dec 20, 2011
210 your idea that there was no genetic change in the fish populations is quite wrong. Wild fish are genetically dominated by traits that help them survive in the wild, in the wild other traits are largly supressed as the eggs that have a higher proportion of the other traits tend not to survive in sufficent numbers to enable single generation changes. However because the fish are raised in a fish farm which does not have many of the variables that would favour the 'wild' genetic traits the fish with less wild traits and more of the other traites would thrive because in the wild such traites are unsuiited for survival and more wastfull, while in the farm they would thive as they are easier so wild traites are not nessasary for survival.

So yes it is evolution as the populations dominent genes are replaced and the wild genes become resessive.
210
1 / 5 (6) Dec 20, 2011
210 your idea that there was no genetic change in the fish populations is quite wrong. Wild fish are genetically dominated by traits that help them survive in the wild, in the wild other traits are largly supressed as the eggs.

Nope: I did not say there was no genetic change. The change HAD to occur before the eggs were fertilised. The ingredients that made mom and pop fish had to be 'changed'/affected before the mom and dad fish mated. In one generation, it should be possible to see what was effected since TIME had been so thoroughly negated and yet one could argue that a type of 'selection' had taken place, though, opposing what is traditionally and historically considered genetically and evolutionarily significant time lapse. Find the points of change and therein reveal the agents of change! That is what made the Dogbert post somewhat compelling and worthy of examination. He may well be on to something and deserves benefit of the doubt.
word-to-ya-muthas
aroc91
2.6 / 5 (5) Dec 20, 2011
Dogbert, historically, evolution has been chained/shackled to TIME.


I can make E. coli plates with antibiotic agar and evolve a population of antibiotic-resistant bacteria in a matter of weeks. Evolution doesn't require any minimum amount of time to pass to occur.

Your argument is not entirely without merit! Especially since you amply your statement by indicating "extreme selection pressures" Recommendation: Advance your argument and do so in a manner that is hermeneutically correct for the discipline of evolution.


How would that change anything?

You have raised a valid point/question! Just how much 'time' and how much 'pressure' can humanity exert in a given time, that is biologically equivalent to the process we know as evolution?!?


A change in gene frequency is a change in gene frequency. This is no different than camouflage-driven predation selection. A quick disappearance of the unfit individuals isn't that unbelievable.
aroc91
3.5 / 5 (6) Dec 20, 2011
Nope: I did not say there was no genetic change. The change HAD to occur before the eggs were fertilised. The ingredients that made mom and pop fish had to be 'changed'/affected before the mom and dad fish mated. In one generation, it should be possible to see what was effected since TIME had been so thoroughly negated and yet one could argue that a type of 'selection' had taken place, though, opposing what is traditionally and historically considered genetically and evolutionarily significant time lapse. Find the points of change and therein reveal the agents of change!


Any population has a certain amount of genetic diversity. Some fish had genes that would benefit them in hatcheries even before they were in the hatcheries. There wasn't a "change" that occurred before the selection, there was just preexisting diversity.

210
1.6 / 5 (7) Dec 20, 2011
There wasn't a "change" that occurred before the selection, there was just preexisting diversity.
If the system is 'alive' and has genes, it has "pre-existing diversity!" It came from something that had genes and became something that had genes. Now the argument is what triggered the kinds of expressions that occurred so quickly: The Triggers and the triggering point. This experiment again shines light on the fact that evolution is as much a servant of survival as man is. evolution is the story of the continuing effort of the living to keep living whether exposed to natural or man-made stimulus. Further, nearly every post on this article lists "TIME" as an ingredient because that IS how the theory of evolution is taught and promulgated. To ignore time is to change the definition and that would be disingenuous. Nope, DogBert's query is worthy of closer examination because it points out the sliver of difference between selection and evolution POSSIBLY!
word-
210
1 / 5 (6) Dec 20, 2011
Dogbert, historically, evolution has been chained/shackled to TIME.


Your argument is not entirely without merit! Especially since you amply your statement by indicating "extreme selection pressures" Recommendation: Advance your argument and do so in a manner that is hermeneutically correct for the discipline of evolution.

How would that change anything?
.

Selection embodied by a manmade effort to accidentally or intentionally impose change, must occur over relatively short period of time because humanity has only been around for a fraction of a second in comparison to the time exercised by the process of evolution! THAT is the difference. Extreme doses of a drug are adminstered to lab animals to synthesize the lapse of smaller doses over TIME. Man has been scientifically aware for a femtosecond compared to the body of work that evolution has effected. Again, this is why Dogbert's post makes sene: He addresses a single generational influx of change visa time!
aroc91
3.4 / 5 (5) Dec 20, 2011
Now the argument is what triggered the kinds of expressions that occurred so quickly: The Triggers and the triggering point.


Selection. The death of fish that didn't have the right genes to handle the crowded conditions of the hatchery.

Further, nearly every post on this article lists "TIME" as an ingredient because that IS how the theory of evolution is taught and promulgated. To ignore time is to change the definition and that would be disingenuous.


Who's ignoring time? Whether it's in one generation or many millions/billions/trillions, of course evolution happens over time.

Nope, DogBert's query is worthy of closer examination because it points out the sliver of difference between selection and evolution POSSIBLY!


I still haven't seen a convincing argument or even an explanation of this. This isn't a hard concept. Evolution is what happens to a population, selection is how it happens, in this case. The population shifted from the natural gene distri
aroc91
3 / 5 (6) Dec 20, 2011
this is why Dogbert's post makes sene: He addresses a single generational influx of change visa time


The population shifted from the natural gene distribution to the augmented one BROUGHT ON by selection. Evolution and selection are two separate, but related things. They're not interchangeable. Evolution happens VIA selection. The environment eliminates unfit fish: Bam! Those genes are gone and the population has changed. Evolution. That's all there is to it. Change in gene frequency over time.
210
1.6 / 5 (7) Dec 20, 2011
this is why Dogbert's post makes sene: He addresses a single generational influx of change visa time

The population shifted from the natural gene distribution to the augmented one BROUGHT ON by selection.

The Dogbert assertion is valid because no one, not you nor the article's experimenters has proven that there were anything called, "augmented genes"! The presence of ANY genes is evident and all that was described...nothing augmented, nothing specially introduced. Those that were present were provoked, triggered for change within one generation, not two, not ten, not a billion! TIME is implied and explicit in all mention of evolution, BUT how SHORT a time is required for genetic change is being demonstrated here where no DNA is/was transferred. The Dogbert assertion is valid as a question and starting point for experimentation. Selection is NOT evolution was Dogbert's assertions and you have now also stated this: that's one for Dogbert!!!
word-
word-
210
1 / 5 (7) Dec 20, 2011
Now the argument is what triggered the kinds of expressions that occurred so quickly: The Triggers and the triggering point.

Selection. The death of fish that didn't have the right genes to handle the crowded conditions of the hatchery.
[P]
There was NO "death of fish" WITHIN a single generation as per the normal spawning act and the ones that might have died in the enclosed pen, had not yet inherited ANYTHING! They were being effected, not the result/offspring of the effect. Dogbert's dilemma is that until we know that some genetic change has been triggered, we cannot stop the stopwatch on how much time this species and every species needs in order to express in ones DNA, the intended change. Because we tend to know in what way the fish are changed -poor reproduction, allows us to pre-emptively state what must be the cause, but, evolution has always been defined as it is in the many posts on this article; by TIME. Dogbert's doubt is based in defined and realized timeliness
Nanobanano
1 / 5 (10) Dec 20, 2011
It's not a genetic change at all, idiots.

It's pavlovian conditioning.

If you lived your entire life in a CELL with no knowledge of how to "hunt" for food for yourself, because you were previously being fed by an owner, and no prior knowledge of what the hunting act was, nor of predators nor predation nor migration, and then suddenly found yourself thrust into the middle of a complete wilderness, you would soon die of starvation, or be eaten by a lion or some other creature.

Fish in a hatchery don't tend to die for any reason, unless your pond loses oxygen or becomes contaminated with a poison or pathogen, and none of that would be "selecting" for any alleged "domestication gene" any more than if those conditions occured in the wild.

I don't think any of you fools have ever dealt with real animals in your ignorant lives. You just listened to your brain-dead professor in college and said, "Uh, huh. That's gotta be right..."
Shootist
2 / 5 (4) Dec 20, 2011

And putting your comment in quotes to imply I said it is dishonest.


Yet accurate.
dogbert
1.7 / 5 (6) Dec 20, 2011
Shootist,

How do you find making up statements (lying) and attributing those lies to someone else to be "accurate"?
signoftimes
5 / 5 (2) Dec 20, 2011
Dude, let's argue over fish and call each other names to show how smart we are. Maybe even attempt to assert dominance by way of attitude and keyboard. Grrr. *Frontal muscular flex*
aroc91
3 / 5 (4) Dec 20, 2011
The Dogbert assertion is valid because no one, not you nor the article's experimenters has proven that there were anything called, "augmented genes"!


"These findings were based on a 19-year genetic analysis of steelhead in Oregon's Hood River"

Augmented gene DISTRIBUTION. Reading comprehension is a fantastic skill; I suggest you use it.

The presence of ANY genes is evident and all that was described...nothing augmented, nothing specially introduced.


You don't need to introduce new genes to change the gene distribution of a population. All you need to do is eliminate the unfit ones, which worked out well enough in one generation, as described, meaning the unfit parental generation fish died, leaving the fit ones to reproduce.

Those that were present were provoked, triggered for change within one generation, not two, not ten, not a billion!


I don't think you're interpreting "change" correctly here. "One generation" is defined as one round of breeding.
aroc91
3.2 / 5 (5) Dec 20, 2011
TIME is implied and explicit in all mention of evolution, BUT how SHORT a time is required for genetic change is being demonstrated here where no DNA is/was transferred.


Again, you're making an assumption. There can't be selection without differential breeding.

The Dogbert assertion is valid as a question and starting point for experimentation. Selection is NOT evolution was Dogbert's assertions and you have now also stated this


Not it's not. Selection is not evolution, but it leads to evolution. Have you just been skimming what I've posted? I've addressed this before. It's very clear in this case that evolution occurred. The population changed due to differential survival and it's only logical the population genetics changed.

There was NO "death of fish" WITHIN a single generation as per the normal spawning act and the ones that might have died in the enclosed pen, had not yet inherited ANYTHING!


It's implied the unfit parentals died and the fit ones didn't.
aroc91
3.4 / 5 (5) Dec 20, 2011
They were being effected, not the result/offspring of the effect.


What do you think happens when unfit fish die and can't reproduce? The fit ones do, eliminating the unfit genes. This is only logical.

Dogbert's dilemma is that until we know that some genetic change has been triggered, we cannot stop the stopwatch on how much time this species and every species needs in order to express in ones DNA, the intended change.


What do you suggest to be the change between the parental generation and the next one then?

Because we tend to know in what way the fish are changed -poor reproduction, allows us to pre-emptively state what must be the cause, but, evolution has always been defined as it is in the many posts on this article; by TIME.


All it takes is one round of selection to eliminate unfit genes. This is demonstrated every day in laboratories.

Dogbert's doubt is based in defined and realized timeliness


Implying there wasn't one round of reproduction.
aroc91
3.4 / 5 (5) Dec 20, 2011
They were being effected, not the result/offspring of the effect


What you're thinking of here is an old and flawed evolutionary hypothesis. A giraffe's neck doesn't grow because it wills it to grow. Its sperm cells don't change because it wants to be taller. There has to be a difference in phenotype due to a difference in genotype and selection based on that. Selective pressure doesn't change your gametes to better fit the environment.
210
1 / 5 (7) Dec 20, 2011
They were being effected, not the result/offspring of the effect

What you're thinking of here is an old and flawed evolutionary hypothesis. A giraffe's neck doesn't grow because it wills it to grow.
You have taken my comment out of context: I AM saying a change took place, "under extreme pressure" as stated by The Dogbert Dilemma and the story. Prior to generational propagation, change had been encoded. The opportunity is to snag some of those Salmon and possibly see an evolutional trigger in action...we now have those tools available to science as we have never had them before! Dogbert's Dilemma and the story firmly dwell on an aspect of TIME: Dogbert's assertion sees too-short-a-time, hence refers to the instance as 'selection' this is not necessarily incorrect. The definition and dogma of EVOLUTION IS always granted and accepted has using appreciable to extended time periods. The Salmon R offering us a chance 2 see change actually happening.
word-to-ya-muthas
210
1 / 5 (7) Dec 20, 2011
Dogbert is not yet proven wrong because all elements that compose/propose a possible direction for selection/evolution do NOT become encoded or expressed! The salmon may be providing us with a window into the what and why of change in larger more complex organisms and their environments...this could be good!
FrankHerbert
1.1 / 5 (54) Dec 20, 2011
The salmon may be providing us with a window into the what and why of change in larger more complex organisms and their environments...this could be good!


Where the Hell are you getting this from dogbert? He said nothing of the sort. He said in paraphrase: "this is not evolution, this is selection." Now you are saying because of dogbert's unique insight we are going to learn the "what and why" (whatever the hell that means) about evolution.

What?

To reiterate, you are saying 1) we can learn from this, which I don't think anyone has disputed, and 2) dogbert's comments have some sort of special insight into this? He said nothing of the sort. Go back and read what he said, then read what you said. They don't follow each other. They aren't necessarily exclusive but THEY DO NOT FOLLOW.

NON SEQUITUR.
210
1 / 5 (6) Dec 20, 2011
TIME is implied and explicit in all mention of evolution, BUT how SHORT a time is required for genetic change is being demonstrated here where no DNA is/was transferred.


Again, you're making an assumption. There can't be selection without differential breeding.

___________THAT is what I am saying has always been the assumption. I am NOT making it, the story is saying it. Change begins BEFORE the males mate with the females. Their life span is so short compared with evolutionary forces as they have been identified and defined that an argument, Dogbert's Dilemma, begs for analysis on a much shorter timescale and rightly so! Each new hatching of salmon may contain many salmon whose parentage were not themselves captive bred! Hatcheries will purchase outside stock to replenish there own gene pool, including stock from the wild...primarily for better size. Then the experiment starts all over and the outcome contains the failure to reproduce well...grab some of these fish!
word
210
1 / 5 (6) Dec 20, 2011
The salmon may be providing us with a window into the what and why of change in larger more complex organisms and their environments...this could be good!


Where the Hell are you getting this from dogbert? He said nothing of the sort.

Franky-Stein; go to Dogberts' FIRST post, the second post there is! "Extreme selection pressures" try not to ignore these things...

210
1 / 5 (6) Dec 20, 2011


I don't think you're interpreting "change" correctly here. "One generation" is defined as one round of breeding


The change is 'seen' after a mating. The offspring ARE the result of mating; The FACT of change is not because a mating took place essentially, but because change was encoded by Dogbert's observed "Extreme selection pressures" in the prior generation. The argument is, " IS that evolution" If people, select traits for commerce does that denote true evolution - that is what it all comes down to. Clearly, we can affect change. Obviously we select traits and apply 'pressure' but the idea that evolution needs vast amounts of time is being tested by the breeding methods used to produce change in these fish. Since the fish are showing poor reproductive proclivities and that would normally hinder a species survival in the wild, Man is becoming evolution and if so, we should be able to see the actual event of change on the molecular level.
Dogbert HAS a point.
word-
210
1 / 5 (7) Dec 20, 2011
We breed dogs... for 'TRAITS'...is that "Evolution" or is that selection... we do need TIME to tell in some cases, but in most, Dogbert is right! Wolves and Dingos are natural predatrs and endure best in the wild. However, loss of habitat, caused by man, loss of clean water - injurious to their long term survival, failing prey species due to over-grazing of human-held herds likewise detrimental to predation, is all pressure that takes time, to cull the top feeders. Few would argue about evolution there - yes, an argument is evident. But PRESSURE is quite evident. Historically, they would only have to contend with nature. Can the lap dog contend under natural pressures against the wolf and dingo? Some would say no, or else they would not have wound up - through TIME- being on Paris Hilton's Lap - that being the only biosphere in which it could survive. Dogbert's observation is NOT faulty. It is in fact a good starting point for some broad arguments in several areas.
word-
FrankHerbert
1.1 / 5 (54) Dec 20, 2011
Anthropologists would tell you it's also evolution as we selected wolves so thoroughly that they speciated into dogs. We did the same with garlic. Pretty much all domesticated animals and many crops have been selected so much they have actually evolved into different species, even though it was at least partially via the hand of humans.

210, dogbert is trying to confuse you. Seems like it has worked.

Here's dogbert's second post you said I should go back to.
You don't seem to know who you are and you don't seem to know that evolution is theorized to result from selection -- it is not the selection process.

More trickery. He's implying the "everything's a theory" crap in a very subtle manner. Typical for him.
You can watch selection. Humans have selected for traits for all of our history in both plants and animals. That is not evolution. It is a common error to confuse selection with evolution.

Third post. Addressed by the above. See wolves into dogs.
aroc91
3.7 / 5 (6) Dec 20, 2011
Jesus Christ, 210, can you read? Lets get back to basics here, because you've convoluted the hell out of this with no discernible goal.

Different genes encode for different traits. This is not disputable.

Please tell me how there can be selection without there being evolution of a population.

Don't give me some roundabout bullshit.

Edit: And just because evolution happens over time doesn't mean it can't happen in one generation (meaning one breeding cycle).
210
1 / 5 (7) Dec 20, 2011
" More trickery. He's implying the "everything's a theory" crap in a very subtle manner. Typical for him."
Franky - maybe the two of you 'bumped heads' sometime back; Just as you and I have! I can still see his point and it is not without merit. He, and Pirouette, and Me and several dozen people have gotten into it with you...and yet, I STILL communicate with you...when you have something to say, Mr. Wright or Mr. Wrong. Selecting traits we like in our food has been presented in the article as possibly occurring within one generation. The selection of traits by humans and their viability as candidates for becoming the evolved creatures of the future is controversial. Dogbert's FIRST post is amendable to a new way of looking at evolutionary triggers. He is not wrong for that. After his first post, he tried to defend himself against attack, some personal - I will have nothing to do with that. These salmon do not do well in nature; Human selection may need closer examination!
word-
aroc91
3 / 5 (4) Dec 20, 2011
The selection of traits by humans and their viability as candidates for becoming the evolved creatures of the future is controversial.


How so? You're trying to give evolution a definition it doesn't have. If we select particular traits, and therefore genes, we've induced evolution in the population. Plain and simple. There's nothing to question here. This is completely comparable to peppered moth evolution and nobody seems to dispute that as evolution.
210
1 / 5 (7) Dec 20, 2011
" Anthropologists would tell you it's also evolution as we selected wolves so thoroughly that they speciated into dogs. We did the same with garlic. Pretty much all domesticated animals and many crops have been selected so much they have actually evolved into different species, even though it was at least partially via the hand of humans."
Selections to meet human tastes may, MAY not be what Evolutionists had in mind. Charles Darwin, or at least, his adherents use the phrase: NATURAL SELECTION and define it as" the nonrandom process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers." Now, if traits selected for by man for commercial goods do not enhance the survivability of that species, in Nature, (poor ability to reproduce) and the selection process imposed is so intense that it occurs in one generation in that one species in a manmade environment, all natural variables pushed aside - hummm???
210
1 / 5 (7) Dec 20, 2011
The selection of traits by humans and their viability as candidates for becoming the evolved creatures of the future is controversial.


How so? You're trying to give evolution a definition it doesn't have. If we select particular traits, and therefore genes, we've induced evolution in the population. Plain and simple. There's nothing to question here. This is completely comparable to peppered moth evolution and nobody seems to dispute that as evolution.

These Salmon when released back into the wild reproduce very poorly. Evolution has been the lynch-pin of species survival universally. We humans intervene for a particular outcome, taste, size, color, texture of meat. We are pursing an outcome that is not an Evolutionary dictum but a culinary one. We make super-drug resistant germs by abusing antibiotics an ethical mis-step that naturally did NOT have to occur and the drugs are man made. It can be argued that this is not D work of Evolution.
word-

aroc91
3.9 / 5 (7) Dec 20, 2011
Selections to meet human tastes may, MAY not be what Evolutionists had in mind. Charles Darwin, or at least, his adherents use the phrase: NATURAL SELECTION and define it as" the nonrandom process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers." Now, if traits selected for by man for commercial goods do not enhance the survivability of that species, in Nature, (poor ability to reproduce) and the selection process imposed is so intense that it occurs in one generation in that one species in a manmade environment, all natural variables pushed aside - hummm?


Now you're implying a dispute that doesn't exist. Evolution is evolution whether it's brought about by natural or artificial selection.
aroc91
4 / 5 (8) Dec 20, 2011
These Salmon when released back into the wild reproduce very poorly. Evolution has been the lynch-pin of species survival universally. We humans intervene for a particular outcome, taste, size, color, texture of meat. We are pursing an outcome that is not an Evolutionary dictum but a culinary one. We make super-drug resistant germs by abusing antibiotics an ethical mis-step that naturally did NOT have to occur and the drugs are man made. It can be argued that this is not D work of Evolution.
word-


Again, the mechanism has no bearing on whether or not it's evolution. It's a change in gene frequency either way and by definition, evolution does not make a distinction between mechanisms. ALL it implies is that gene frequencies of a population change.
dogbert
1.4 / 5 (10) Dec 21, 2011
ALL it implies is that gene frequencies of a population change.


That is not evolution. Evolution posits speciation from changes as a result of selection, mutation and genetic drift.

Selection is a mechanism, a process. It does not represent evolution.

Adult human beings who can drink milk, for example, represent such a change selected in herders. Those human adults who can drink milk are not a new species of human being. They simply have a specific trait which is lacking in much of the population.

All dogs are dogs, despite excessive selection pressures which human beings have placed on them. They are examples of selection, not evolution.
FrankHerbert
1.1 / 5 (54) Dec 21, 2011
That is not evolution.

Actually it is. Change "gene" to "allele" and you actually get the textbook definition. Go ahead, open one up.

All dogs are dogs, despite excessive selection pressures which human beings have placed on them. They are examples of selection, not evolution.

Dogs evolved from wolves dogbert. You are intentionally conflating what I said. Humans (as part of nature) and nature selected wolves until they became dogs. You can scream "dogs are dogs" until you are blue in the face but it doesn't change that fact the wolves ARE NOT dogs and humans most certainly had a hand in that evolutionary process.

Please stop your dishonesty dogbert. It's becoming obvious in this topic.
dogbert
1.4 / 5 (11) Dec 21, 2011
Frankie,
The term evolution as it applies to biological systems has a distinct meaning. You may certainly argue that the word simply means change, but then you rob the word of meaning. Since I presume you accept evolution as the mechanism driving diversity, I don't see why you want to make the word essentially meaningless.

FrankHerbert
1.1 / 5 (55) Dec 21, 2011
dogbert, you are the one trying to make the word meaningless so you can say to scientifically minded people you believe in it while not accepting any of its implications.

Are you willing to admit wolves evolved into dogs, or will you continue ignoring that and just respond with "dogs are dogs"? You have a history of ignoring the parameters of questions asked to you and providing either irrelevant or vague answers. This is because you are intentionally dishonest and know your ideology does not stand up to scrutiny in such a forum as this.

Since we cannot agree on a definition of evolution, will you say unequivocally that speciation via evolution occurs? Just in case you decide to go on another obfuscation spree, I'll reword the question as simply as possible.

Does speciation occur? Please provide an example of an organism that has speciated into another. Any will do. I just need to hear "X evolved into Y" or something equivalent come out of your mouth.

I have no faith in you though.
aroc91
4.1 / 5 (9) Dec 21, 2011
That is not evolution. Evolution posits speciation from changes as a result of selection, mutation and genetic drift.


No. Stop it. You can't change the definition to suit your own agenda.

Evolution- any change across successive generations in the heritable characteristics of biological populations

JUST BECAUSE IT'S NOT A NEW SPECIES DOES NOT MEAN IT'S NOT EVOLUTION. At this point, you're clearly trolling.
dogbert
1.4 / 5 (10) Dec 21, 2011
aroc91,

Your welcome to believe that evolution means just change. Change is indisputable and evident to everyone. The question you present with your insistance on defining evolution as merely change is why you continue to use the term evolution when you have stripped it of meaning. Why not just use the word change?
aroc91
3.9 / 5 (7) Dec 21, 2011
"Stripped it of its meaning"

What? It means exactly what it means, a change in the genetics of a population. What are you getting at? Neither the speed at which it happens nor the mechanism matter.

Humans can evolve to become taller and still be humans, if you're going to bring up your "its not evolution if it's still the same species. This is convention. Most, if not all, of the scientific community has absolutely no problem with this definition.

So then it begs the question- how would YOU define evolution and precisely why isn't the conventional definition satisfactory?
aroc91
3.7 / 5 (7) Dec 21, 2011
Why not just use the word change?


Because there's a bit more to it than that- it's the change in genetics over time.

"Change" by itself is so vague. Even then, you'd have to describe what is changing, bringing you back to the conventional definition, but taking more time to do so.

But then you could carry on your current point and say "well, why not describe the mechanisms in the definition as well?" to which I would say that if you read a dictionary, a definition of a word isn't an endless tree of definitions of each of the words within the definition itself, so why should it be that way for "evolution"?

If you want to learn further, there are plenty of resources by which to do so besides merely the basic definition.
aroc91
3.7 / 5 (6) Dec 21, 2011
If you have something to say, 210, say it. If you don't have a valid criticism, then keep your 1's to yourself. I'm trying to be civil here and I've made a point to respond to every post.
dogbert
1.8 / 5 (12) Dec 21, 2011
aroc91,
As I said, you're welcome to diminish the word evolution. I prefer for such words to retain their meaning, but you don't have to care about such things.

FrankHerbert
1 / 5 (53) Dec 21, 2011
Can anyone really deny my description of dogbert's M.O.? I'll post my question again:

Does speciation occur? Please provide an example of an organism that has speciated into another. Any will do. I just need to hear "X evolved into Y" or something equivalent come out of your mouth.


dogbert,
As I said, you're welcome to diminish the word evolution. I prefer for such words to retain their meaning, but you don't have to care about such things.
aroc91
3.3 / 5 (6) Dec 21, 2011
I'll ask you again because you're conveniently ignoring parts of my posts: How would you define evolution and precisely why isn't the conventional definition satisfactory?

Edit: And I do care about such things because your interpretation of it goes against accepted convention that has been used for decades.
dogbert
1.6 / 5 (7) Dec 22, 2011
aroc91,
How would you define evolution and precisely why isn't the conventional definition satisfactory?


I already said it, but I'll say it again. The concept of evolution was created to posit speciation as a result of selection ( with the later addition of the mechanisms of mutation and genetic drift ).

You choose to redefine evolution to be any change whatsoever, even changes which are clearly not related to speciation.

People have selected for traits for all of our history. Change is universally accepted as a part of biological processes in the presence of selection. Prior to the work of Darwin and others of his time, we had no theoretical mechanism for speciation. Evolution theory provides that mechanism.

You diminish the word and concept when you redefine it to mean just change. The concept of speciation is an important concept.

aroc91
2.3 / 5 (3) Dec 22, 2011
I see where you're coming from, but alas, I'm not going to be able to change your mind.

So: You would only consider drastic mutations, fragmenting populations due to an inability to breed, as evolution, such as a change in chromosome number? You wouldn't consider dinosaurs developing feathers as evolution?
dogbert
1.4 / 5 (9) Dec 22, 2011
So: You would only consider drastic mutations, fragmenting populations due to an inability to breed, as evolution ...


No. You have been arguing that any change is evolution. I have been arguing that it is more than just change.

You will doubtless continue to argue that the process is the result and that every process is the result. Not scientific, but I don't see any way to redirect you.

aroc91
3.3 / 5 (4) Dec 23, 2011
Thanks for the 1, 210, you've been an excellent contributor lately.

No. You have been arguing that any change is evolution. I have been arguing that it is more than just change.

You will doubtless continue to argue that the process is the result and that every process is the result. Not scientific, but I don't see any way to redirect you.



As previously stated-

"I'm not going to be able to change your mind."

I'm just in it for the clarification now. Can we get back to that and not do this roundabout bullshit?

So you would only consider mutations that produce separate, non-breeding populations as evolution?

Simple question, simple answer.
Thrasymachus
3.2 / 5 (5) Dec 23, 2011
"Species" is not a relevant concept when discussing evolution. There is no natural category of "species." In nature, there are only organisms, more or less closely related to one another. Even the nature of reproduction, whether through sexual reproduction with another closely-related organism, or through budding or mitosis, is irrelevant. Evolution occurs even in populations of organisms which do not sexually reproduce.

Evolution is not just "change in general" because it is specifically the change in the distribution of characteristics from generation to generation. It's not change in general, because it's not talking about how rocks change due to erosion, and it's not talking about change in general in a group of organisms because many organisms change quite drastically as they mature. It's talking about change between generations attributable to differential success in reproduction.
aroc91
3 / 5 (3) Dec 23, 2011
It's talking about change between generations attributable to differential success in reproduction.


Not necessarily. There doesn't have to be selection for evolution to take place. What about neutral mutations that don't affect survival and don't have any effect on reproductive success?

Edit: and yes, I do agree with your first part. Species is an arbitrary man-made idea.
Thrasymachus
3 / 5 (4) Dec 23, 2011
A lack of strong selection pressure is still selection. Even when the vast majority of the organisms that make up a given population survive to reproduce, that type of selection allows the proliferation of neutral mutations throughout the population. Higher selection pressures means neutral mutations don't spread through the population as rapidly, if at all. Selecting 100% of the members of a population to reproduce is just as much selection as selecting only 20%. The only kind of "selection" which isn't selection is extinction, where none of the members of a population survive to reproduce. As long as there is reproduction, there is selection.
Thrasymachus
3.3 / 5 (4) Dec 23, 2011
In other words, the proliferation of neutral mutations through a population is still attributed to the differential success of reproduction, in this case, to the relative lack of differences in success. Selection is still the cause of the proliferation of neutral mutations, because if you changed selections, you'd change the pattern of proliferation.
aroc91
3 / 5 (2) Dec 23, 2011
Selection implies differential survivibility. If a mutation is truly neutral, then there will be no difference.

the proliferation of neutral mutations through a population is still attributed to the differential success of reproduction, in this case, to the relative lack of differences in success


Which is implied by "neutral"

Edit: So if a trait is neutral there isn't selection for or against, and its proliferation just comes down to random chance.

rocky j squirrel
5 / 5 (2) Dec 24, 2011
These comments are like New York Taxi riders arguing about which is the best pickup for Ranching.
Background I am a Fish Bioligist U of Wash '68 well aquainted with Aquaculture.
The managment or the Migratory Fisheries in the NW has two factions: Natural production and Hatchery propagation; and they have argued for decades, this study is a response to the fray.
Rainbow Trout in all its variations (Steelhead sea run to the hyper domesticated hatchery raised food market trout) all have the set of genes that perpetuated their Line in the enviorment it lived in.
Hatchery production yeilds fish for suitable for hatchery opperations, and the wild produces fish that hedge their bets with variablity in case of changed conditions to enhance long term survival and do very poorly in hatcheries (I have raised both side by side).
Epigenetics: a soft hatchery life yeilds lazy fish. Emerging from gravel into current and predation turns on some genes that hatchery life does not.
TheGhostofOtto1923
2.7 / 5 (7) Dec 24, 2011
"Species" is not a relevant concept when discussing evolution.
Uh not according to experts?

"A usable definition of the word "species" and reliable methods of identifying particular species is essential for stating and testing biological theories and for measuring biodiversity. ...

"Some biologists may view species as statistical phenomena, as opposed to the traditional idea, with a species seen as a class of organisms. In that case, a species is defined as

a separately evolving lineage that forms a single gene pool.

"Although properties such as DNA-sequences and morphology are used to help separate closely related lineages, this definition has fuzzy boundaries. ...Biologists have proposed a range of more precise definitions, but the definition used is a pragmatic choice that depends on the particularities of the species of concern."

The Internet is always there, do not forget that.
Jaeherys
not rated yet Dec 24, 2011
@rocky j squirrel
Finally someone mentioned EPIGENETICS! There has been so much debate over "how to define evolution" but the definitions being used range over decades and there are key differences causing problems here.

The most important difference to note is that evolution can happen over the lifespan of a single individual by the fore mentioned epigenetics.

A more, full definition of evolution would be the change of phenotype by the mechanisms of selection, mutation, genetic drift (e.g. cross over) and epigenetics (typically, a change of gene expression by environmental factors).

As of late, that is the definition I hear most compared to that of previous definitions which left out epigenetics and included speciation and genotypic changes.

With respect to selection though, biochemically there is no distinction between natural/artificial or high/low selective pressure. Therefore any debate about human selection not causing evolution is non sequitur.
DavidMcC
not rated yet Dec 25, 2011
All so that Steelhead trout can end up on the dinner plate..... what a shame....


With a human population of 7Bn and rising, it isn't a trivial matter, shifty. I think the best option would be to somehow nake the farmed fish into a new species, so that escaped fish don't damage the survival chances of wild ones.
Thrasymachus
3 / 5 (2) Dec 25, 2011
Traits, by themselves, are neither selected for or against. Only organisms are either selected to reproduce by surviving, or not selected by failing to survive to reproduce. If an organism has an unique mutation that gives it a massive advantage to survival, while at the same time possessing another, unrelated mutation that is lethal, that advantageous mutation is selected against because the organism that possesses it will not survive to reproduce. As far as evolution is concerned, epigenetics is nothing more than an interesting way in which genomes are mutated. Evolution still does not occur within a single organism, because evolution by definition is those changes that occur in a population from one generation to the next as a result of the selection to reproduce or not.
TheGhostofOtto1923
3 / 5 (6) Dec 25, 2011
Traits, by themselves, are neither selected for or against.
Yawn again I would defer to experts:

"In fact, if you were told which traits evolved on which branches, you could precisely predict which traits each living species would have. Conversely, if given the features of each living species, you could explain the variation between the species by invoking just four events of trait evolution."
As far as evolution is concerned, epigenetics is nothing more than an interesting way in which genomes are mutated.
And again:

"The organism experiences its environment in one continuous nested process, adjusting and changing, leaving imprints in its epigenetic system, its genome as well as on the environment, all of which are passed on to subsequent generations. Thus, there is no separation between development and evolution."

You should really read through this before posting again:
http://www.i-sis....yclo.php
Thrasymachus
3 / 5 (2) Dec 25, 2011
Keep trying Otto. Maybe you'll come across a quote in your googling you can cherry-pick that has something relevant to say about what I wrote. Perhaps one of the clandestine Leaders of your Pan-Historical, Omniscient, Omnipotent and Benevolent Empire can point you in the right direction.
TheGhostofOtto1923
2.3 / 5 (6) Dec 25, 2011
Keep trying Otto. Maybe you'll come across a quote in your googling you can cherry-pick that has something relevant to say about what I wrote.
I just do a little research, look up definitions, and show how you like to pretend. Its easy.

See if you referenced your stuff then I wouldnt have a leg to stand on. But then I guess it is hard to reference yourself unless you have a website like zephyr/jigga.
Perhaps one of the clandestine Leaders of your Pan-Historical, Omniscient, Omnipotent and Benevolent Empire can point you in the right direction.
Naw anybody can poke holes in your fabrications. Thats what the internet is for.
Ethelred
3.3 / 5 (10) Dec 28, 2011
you don't seem to know that evolution is theorized to result from selection -- it is not the selection process.
Selection is half the cause of long term evolution. The other half is mutation. This article is about evolution via selection. The cause of the change in the species was the change in environment changes what constitutes a successful combination of genes.

Your calling it mere selection doesn't stop it from being part of the evolutionary process.

And putting your comment in quotes to imply I said it is dishonest.
You got that right.

It's not dishonest if it's true and either way, I don't give a rat's ass.
It was a lie. You are a rats ass. I give rats asses ones.

Evolution is a change in a population over time.
True. You changed into a rats ass.>>
Ethelred
3 / 5 (10) Dec 28, 2011
You can watch selection. Humans have selected for traits for all of our history in both plants and animals. That is not evolution. It is a common error to confuse selection with evolution
Its a common evasion by Creationists to deliberately confuse the subject.

THIS IS THE DEFINITION. THIS IS NOT DISPUTABLE
Wanna bet? Its the definition of some people not everyone.

If yes, that is, within a single NON-breeding period - no exchange of DNA has occurred- what were the triggers and where did they have the greatest effect?
The environment changed and that was the trigger. It had the greatest effect on who survived to reproduce. The article supposed crowding as the main cause. I suspect the food source was more important. One single kind of food that the fish did not have to learn very much about. Stupid fish were more likely survive than in the wild. Crowding would likely be secondary UNLESS young salmon have a severe problem with crowding.>>
Ethelred
3 / 5 (10) Dec 28, 2011
So yes it is evolution as the populations dominent genes are replaced and the wild genes become resessive.
Not in one generation. There can be no replacement by new genes in just one generation. All that can happen is a culling of both specific genes and combinations of genes. Selecting OUT is all that is happening here.

I can make E. coli plates with antibiotic agar and evolve a population of antibiotic-resistant bacteria in a matter of weeks.
That is multiple generations and if you start with E. Coli that have resistance already or there is contamination by bacteria that are resistant and can exchange genes with E Coli then you have only emphasized certain genes or combinations of genes. IF you start with E. Coli with no resistance and there is no contamination THEN you have significant evolution and with all those generations over weeks that would be evolution. To you and me. Not to a Creationist who I guarantee will only respond that they are still bacteria.>>
Ethelred
3 / 5 (8) Dec 28, 2011
I can make E. coli plates with antibiotic agar and evolve a population of antibiotic-resistant bacteria in a matter of weeks.
Only if you use that crappy definition.

How would that change anything?
Well the Creationists would still say the result was still bacteria BUT they would also claim it human intervention.

A change in gene frequency is a change in gene frequency.
Yes but that is not evolution. You can't get speciation that way and speciation is a key part of evolution.

The Origin of Species by means of natural selection, not a change in gene frequencies by a Monk that Darwin never heard of. I don't think Wallace would have agreed either.

A quick disappearance of the unfit individuals isn't that unbelievable.
That is clearly what was going on.

Any population has a certain amount of genetic diversity.
Nearly any wild population not including Cheetahs.

Ethelred
Ethelred
3 / 5 (8) Dec 28, 2011
Nope, DogBert's query is worthy of closer examination because it points out the sliver of difference between selection and evolution POSSIBLY!
Not really. This because of motivation. Dogbert desperately wants to make speciation go away.

Selection embodied by a manmade effort to accidentally or intentionally impose change, must occur over relatively short period of time because humanity has only been around for a fraction of a second
Irrelevant. Change in the environment is still change in the environment whether it is by human intervention or a meteor strike or an earthquake.

Dogbert's doubt is based in defined and realized timeliness
No. Dogbert's doubt is based on his religion not biology.

I see Doggy is giving me ones for supporting him about the lie. Well Doggy knows that means.

Ethelred
Ethelred
3.3 / 5 (9) Dec 28, 2011
QC
It's not a genetic change at all, idiots.

It's pavlovian conditioning.
Speaking of idiots. That was idiotic. Stick to math and let someone else do the word problems.

If you lived your entire life in a CELL with no knowledge of how to "hunt" for food for yourself,
This allows those that can't learn to survive. Not conditioning AND it has nothing to do with the next generation which is what is failing to survive in the wild. Do read the article. If it helps you could write down in some kind of symbolic notation what is going on and when the reproduction occurs. You missed that last part completely.

I don't think any of you fools
I think you are the fool here. You can't read.

Ethelred
Ethelred
3 / 5 (8) Dec 28, 2011
Shootist,

How do you find making up statements (lying) and attributing those lies to someone else to be "accurate"?
The problem is that it was accurate. You don't understand evolution mostly because you don't to. Still, he was dishonest.

You don't need to introduce new genes to change the gene distribution of a population.
You do to have speciation.

210
Prior to generational propagation, change had been encoded.
No. There is nothing that encodes the DNA besides a RNA virus. No species has a way to change the DNA except to increase the mutation rate and that is not encoding change it is random change.

The opportunity is to snag some of those Salmon and possibly see an evolutional trigger in action
No.

..we now have those tools available to science as we have never had them before!
Those tools have already shown there is no way to encode change in the phenotype to the genotype.>>
Ethelred
2.5 / 5 (6) Dec 29, 2011
Dogbert is not yet proven wrong because all elements that compose/propose a possible direction for selection/evolution do NOT become encoded or expressed!
None are.

The salmon may be providing us with a window into the what and why of change in larger more complex organisms and their environments
No. Go learn some biology. There is no way for the DNA to change except

Viral infection by retro viruses
Mutation - this can be caused by stress hormones BUT the mutations will be random.
Genetic engineering

I think that covers all the ways.

Ethelred
Ethelred
3 / 5 (6) Dec 29, 2011
"Species" is not a relevant concept when discussing evolution. There is no natural category of "species."
Yes there is. The ability to interbreed successfully. There is not natural category ABOVE species.

In nature, there are only organisms, more or less closely related to one another
No. Not in sexually species. That claim only fits non-sexually reproducing species.

Evolution occurs even in populations of organisms which do not sexually reproduce.
Not for long. If they don't have genetic recombination with related organisms they will die out except perhaps in clonal organism that simply don't have any competition.

Ethelred
Ethelred
3 / 5 (6) Dec 29, 2011
What about neutral mutations that don't affect survival and don't have any effect on reproductive success?
Those don't result in changes that are detectable. No speciation will occur and there is no adaptation.

Species is an arbitrary man-made idea.
Bullshit. Life created species when sexual reproduction evolved. I agree that non-sexually reproducing organisms don't have species. We mammals certainly do as do all other sexually reproducing species.

From Otto's link:
(c) there is no feedback from the environment to the organism's genes. All three assumptions have been demonstrated to be false.
This is wrong. There is no feedback except for that of stress related hormones. That was written in 1966 and its just wrong.

Ethelred
CHollman82
1.4 / 5 (13) Dec 30, 2011
Species is an arbitrary man-made idea.
Bullshit. Life created species when sexual reproduction evolved.


Our current definition of species is a group of organisms that can interbreed and produce fertile offspring. That is our CURRENT definition, it didn't used to be that way, species has meant many different things over the past few decades.

Species is a categorization, and all categorizations are man made. Nature does not categorize or classify. Each individual organism is unique, humans create systems of classification in order to ease the burden of identification for the purpose of communication. By classifying anything into a group you select specific traits that you consider important to use as a demarcation while simultaneously ignoring those traits that make each of those entities unique.
aroc91
3 / 5 (2) Dec 31, 2011
@Ethelred

Those don't result in changes that are detectable.


What? Where, exactly, does "neutral" convey that it isn't detectable? You can't make a broad judgment like that without even considering what types of mutations can produce alleles with the same survival rate. How about eye color?

No speciation will occur and there is no adaptation.


Of course not, because mutations like that don't invoke shifts in chromosome number or otherwise fragment populations and there can't be adaptation without differential survival.
Ethelred
3 / 5 (4) Jan 10, 2012
CHollman82, you are arguing about definitions. I am dealing with how reproduction actually works and using species as the label so we can use a common language.

Species is the ONLY classification based on actual biology. It isn't my fault that biologists keep trying to use variants of definitions that don't fit actual biology. If you don't like the word defined as:

Sexually reproducing organisms that are capable of interbreeding are members of the same species.

Then please produce a word that fits that definition as it is biologically correct and any other is not. It is just plain counterproductive to use words that cannot convey meaning.

Is this getting across? Why I don't like argument by definition when we are trying to talk about what is really going on?

Ethelred
Thrasymachus
2.5 / 5 (2) Jan 10, 2012
Species can be a convenient term in order to differentiate groups of organisms from other groups, but sexual reproduction, which is the only basis for which any kind of natural speciation can be maintained, is not essential to evolution.

Organisms that only reproduce by budding or splitting do not eventually die out, and indeed, that kind of reproduction, as long as it introduces errors, is sufficient. Reproduction, selection and mutation are all that's required for evolution to proceed. Sexual reproduction is just a fancy way of producing new mutations, which can include new combinations of already existing traits.
Ethelred
3 / 5 (4) Jan 11, 2012
but sexual reproduction, which is the only basis for which any kind of natural speciation can be maintained, is not essential to evolution.
It speeds it up considerably and that is not all it does.

Organisms that only reproduce by budding or splitting do not eventually die out,
I think new lines of descent in those die off at a higher percentage rate than sexual species do. Every mutation produces a new line of descent. There aren't very many lines from what I can see.

that kind of reproduction, as long as it introduces errors, is sufficient.
It is sufficient for lines of descent that are already well adapted and are not competing with sexually reproducing species. Sponges don't have a lot of competition except for other sponge lines of descent and they evolved a long time ago.>>
Ethelred
3 / 5 (4) Jan 11, 2012
Reproduction, selection and mutation are all that's required for evolution to proceed.
Never said otherwise. However it is not always enough to avoid extinction. Those parthenogenic whiptails are a dead end UNLESS they can produce a male when the conditions change.

Sexual reproduction is just a fancy way of producing new mutations, which can include new combinations of already existing traits.
No that is not right at all. First, new combinations are not mutations BUT they can do similar things. So don't muddle the two as new chemicals can do things no combination can. Second it is NOT a way to produce mutations. It is way to form new combinations but that is not the primary advantage.>>
Ethelred
2.3 / 5 (3) Jan 11, 2012
The primary advantage is that the ancestors are no longer dependent on a single line of descent to have descendants continuing in the future. The species is NETWORK of descent. The network can branch to form specialized networks and sometime even highly modified networks can reconnect as Homo Sapiens and Homo Neanderthalis seem to have done.

The network is the key difference. Bacteria can form reproductive networks without having separate sexes. In fact you see sexual reproduction without a species having specialized sexual pairs. The is a flatworm species that shows how it might have started, a flatworm is believed to have been the ancestor of the vertebrate species. Two individual flatworms compete to impregnate the other by driving a penis into the other flatworm. There is no vagina or cloaca. The penetration is quite literal and the penetrated flatworm is the one that has to produce the offspring.>>
Ethelred
3 / 5 (4) Jan 11, 2012
The sheer success of sexual reproduction means that there is a reason it developed. The question many ask is since both parents only have half their gene passed on to any particular offspring why did it happen?

The answer is that they are looking at it the wrong way. Sexual species ARE the offspring. The whole lot is the offspring of the organisms, yes plural, that first produced offspring that could do that gene swap thing. A network of descent is more likely to succeed in the long run vs. individual lines since the mutations can be shared across the network over time.

This is related to some of the seemingly stupid claims Creationists make about there not being enough time. There hasn't been enough time for, oh say, vertebrates to move from the ocean to the trees IF they had to develop mutations along a single line. Each generation would get only so many chances to get a successful mutation and most mutations would be either neutral or fatal.>
Ethelred
2.3 / 5 (3) Jan 11, 2012
But with a network the fatalities don't stop the network. The successes aren't limited to a single line.

As far as I can tell I am the only person thinking about it this way at the moment. Dawkins comes close as he knows species form a network of reproduction but he doesn't seem to have thought of it in any way except in terms of last common ancestor. Maybe a hint in a book I read last month by Earnst Mayer.

Ethelred
Thrasymachus
1 / 5 (1) Jan 11, 2012
Variation, selection and reproduction are all that's required for evolution. Sexual reproduction is merely an interesting way of introducing new kinds of variation. It is certainly advantageous, but by no means necessary, to the process of increasing complexity through evolution.

Many microorganisms are capable of swapping genes cross-species and then reproducing having both daughter cells with the newly acquired gene and trait. This does not make microorganisms capable of such feats members of the same species.

I'm not downplaying the importance of sexual reproduction for the relatively rapid development of complex traits. I'm just saying that an understanding of sexual reproduction and speciation is not necessary to grasping the basic mechanics of evolution.
Ethelred
3 / 5 (4) Jan 11, 2012
Variation, selection and reproduction are all that's required for evolution.
You said that. I agreed with it. What part of 'yes' did you fail to understand?

Sexual reproduction is merely an interesting way of introducing new kinds of variation.
Horseshit. Its a vastly superior way.

It is certainly advantageous, but by no means necessary, to the process of increasing complexity through evolution.
Again where did I say otherwise? I did say that without some kind of exchange evolution would take much longer. Did you have problem with that?

Many microorganisms are capable of swapping genes cross-species and then reproducing having both daughter cells with the newly acquired gene and trait.
I said that or rather something equivalent.

This does not make microorganisms capable of such feats members of the same species.
Actually is does if you want to use the word with bacteria. If you don't you need an alternative word. I asked if you had one.>>
Ethelred
3 / 5 (4) Jan 11, 2012
So I will use species until someone comes up with a better word.

I'm not downplaying the importance of sexual reproduction for the relatively rapid development of complex traits.
NOW. In that one sentence.

I'm just saying that an understanding of sexual reproduction and speciation is not necessary to grasping the basic mechanics of evolution.
And where the heck did I say otherwise?

I am looking for a point in your comments. They seem to be directed at me as if I said things I didn't. Am I being paranoid or are you failing to make your point?>>

I hate that stupid 1000 character limit.
Ethelred
2.3 / 5 (3) Jan 11, 2012
What I was doing is making the importance of sexual reproduction clear. It was a MAJOR change in life on Earth. It may even have happened shortly before the Cambrian Explosion. The sort of gene exchange that goes on with bacteria cannot occur in eukaryotes. And even in bacteria there isn't the pairing of genes that allows sexually reproducing species to have a functioning gene even if the other mutates into something different but still useful. This is almost as important as the networking. Maybe more so but I don't think so.

Now if you have a problem with my species as networks idea I would appreciate knowing what it is as I could use some rational feedback. It keeps getting ignored as if it was somehow a new way to do the Frug or the Watusi* or something equally irrelevant to all that is rational.

*Two rather silly dance forms from the late fifties shortly before the British Invasion. I feel ill that I remember that they ever existed.

Ethelred
aroc91
3 / 5 (2) Jan 11, 2012
Ethelred-

Not in one generation. There can be no replacement by new genes in just one generation. All that can happen is a culling of both specific genes and combinations of genes. Selecting OUT is all that is happening here.


... Obviously. I NEVER implied there were NEW genes, just a new gene DISTRIBUTION.

On a side note- would you say that a change in gene distribution due to genetic drift is evolution?
Ethelred
3.3 / 5 (4) Jan 12, 2012
. Obviously. I NEVER implied there were NEW genes, just a new gene DISTRIBUTION.
Which is part of the process of evolution. The thing is mere change in the distribution, as you wrote it, is fully reversible. Gene loss is not reversible if the entire gene pool no longer has it.

On a side note- would you say that a change in gene distribution due to genetic drift is evolution?
Not as you wrote it. The idea that a change in gene distribution is a key part of Darwinian Evolution, that is with The Origin of Species, is supposed to have gone away decades ago.

Genetic drift IS part of how evolution occurs. Mostly via gene LOSS not mere redistribution. I don't see how reversible change is going to produce new species.

To put in terms that Dogbert seems to like. Redistribution of genes, or rather changes in gene frequencies in a gene pool, is mere adaptation. While it is part of evolution it isn't enough to create new species and it sure isn't adding complexity.

Ethelred