Uncommon Descent Serving The Intelligent Design Community

Sounds Fishy (or, How to Get Published at AAAS)

Share
Facebook
Twitter
LinkedIn
Flipboard
Print
Email

unScientific American and Science News are reporting in (this) story that “darwinian debt”s are being generated by over-fishing and the result is that

Fast-growing fish therefore get penalized evolutionarily because they quickly become large enough to get caught…

Correct me if I’m wrong, but isn’t this nothing more than an exagerated example of dog-breeding (except with fish, of course)?

In the present case of these Atlantic silversides, isn’t Dr. Conover merely controlling the reproductive environment in order to diminish the size, growth rate, and sexual appetite of the resulting breed by taking advantage of the existing gene pool? By removing the largest 90% of fish periodically, isn’t that the same as only allowing dogs with big floppy ears to procreate thus increasing the chances of getting a floppy-eared dog? Variation within kind based on an existing genome without any mutation-driven change can hardly be called evolution.

But there is important value to this experiment. As an avid fisherman I recall a time 20 years ago when I was fishing the upper end of Yellowstone Lake. Back then regulations required that I throw back any fish larger than 12 inches. It seemed silly at the time because conventional wisdom dictated it was best to release the small ones so they could grow up and breed at least once. When I asked a ranger at the park about it, he explained that they had surmised that it would be better to let the older, larger fish live so they could reproduce over a number of years – since as they grew larger they also produced more eggs and offspring, etc.

So it seems this study is just reiterating old news (by at least 20 years).

That’s all well and good, but why does this report presented to the American Association for the Advancement of Science try to draw Darwinian evolution into a place it clearly does not belong? My guess is that the authors know the power and influence of the word “Darwinian” when it comes to getting published. They would have been better off dropping the Darwinian Red Herring and presenting this paper to organizations who can actually use the information to help preserve fish species. I assume they (the authors) didn’t do that because, well… it’s old news.

My question is: if the authors had not included mention of Darwin, would they have been published by the AAAS?

Comments
"My guess is you’re blowing hot air and any number of unknowns could reverse which mi[g]ht act faster. ... Meanwhile for all you know the needed environmental cues could take hundreds of generations to become established and trigger any change." And I'm blowing hot air? The reason an environmental response will be faster is simply that every fish is primed to respond, so if the environment changes, so will they. Hence, if we stop fishing and this means that the environment returns to the pristine state, the fish would revert in one generation. In reality, the changes would almost certainly take longer, if only because the numbers of fish (and other parts of the ecosystem) will take longer to recover. If the change are genetic, then it will take longer, simply because the genes which are now fitter have to be selected back into the population. Your statement about large fish is true, and is (of course) already figured into the Breeder's equation. Even if we take the simplest case, where there is a single gene in a haploid population with two alleles ("big" and "small"), then the change in frequency can be calculated from this equation (originally from Haldane in the 1920s): logit(p_t) = t*log(1+s) + logit(p_0) where logit(x)= log(x/(1-x), p_t is the frequency of the fitter allele at time t, and s is the relative fitness of the fitter allele. Total replacement takes infinitely long, but if we assume that the fitter allele is twice as fit, then it tales about 10 generations to go from 1% to 90%. This will be slower in practice, because there will be more than 1 gene involved, and hence recombination, and the relative fitness probably won't be as large (because there is a lot of environmental variation, for starters). BobBob OH
April 18, 2006
April
04
Apr
18
18
2006
11:36 PM
11
11
36
PM
PDT

"I think Michaels7 is asking what the fuss is all about since the science of fishery management already understands how to manage the population through both selective breeding and population density."

They weren't aware that selective breeding would have an effect: it's less obvious that it appears (read the paper by Dieckmann & Heino & co). Advice about keeping larger fish was not about evolution per se, but was because (as I understand it) larger fish are more fecund, so they can produce more offsring, and hence replenish the stocks quicker.

"Just for kicks, since you seem convinced that “evolution” is slower than environmental cues about when (sizewise) to reach sexual maturity, how long does NeoDarwinian theory predict it takes these fish to “evolve” back to a larger size through selective breeding and how long it takes these environmental cues to acheive the same size increase. "

If the response was just due to environmental cues, then it would take a couple of generations (in principle it would take one, but there's always the problem that there's a different environment so the population will have to re-equilibriate). If the response had been evolutionary, then the change would depend on the additive genetic variance in the population: you can calculate it from the Breeder's equation (first derived by Fisher in 1918). The additive variation will have been depleted by the selective breeding, so it will almost certainly be slower than the initial change due to the fishing. In addition, the selective pressure is probably also less, so that will make things slower too. My guess is that it would be tens of generations at least, but I haven't done the calculations, so I might be wrong.

Bob

I'm quite certain fish & wildlife managers know about selective breeding. Perhaps to you it's rocket science but it's basic animal husbandry for everyone else. Further, even though you don't know what specific environment cues are operating or how long it takes to reacquire equilibrium you guess it's a couple generations and you guess its tens of generations for selective breeding to produce bigger fish. My guess is you're blowing hot air and any number of unknowns could reverse which mibht act faster. There are likely some evolved bigger fish still in the population since they were big in the past and where if they aren't heavily harvested will immediately produce large offspring in exponentially growing numbers. Meanwhile for all you know the needed environmental cues could take hundreds of generations to become established and trigger any change. -ds

Bob OH
April 18, 2006
April
04
Apr
18
18
2006
08:12 AM
8
08
12
AM
PDT

I'll try again: hopefully someone at UD believes in having a sensible discussion.

Michaels7 wrote
"No better examples exist than wildlife management as experimental evidence for farming of different fish species. Yes, Fish and Wildlife have done it as I said since before 1900. They had no choice due to overfishing in lakes and streams. If they did not “trout fishing in America” would’ve been history long ago. And yes they kept statistics. Some of them ‘ole boys’ even had college degrees Bob!"

Here you're not talking about evolution, but conervation and ecology. Overfishing is going to have a larger ecological effect, because the time scales are shorter: essentially, the population can go extinct before it has a chance to evolve. Over the last few years, there has been work on "evolutionatry rescue", but little convincing evidence that it works in practice.

Michaels7 wrote
"Explain how the same fish can reproduce larger stock in a larger pond? Or smaller fish in smaller tanks?"

I expanded on this in a post that got dinged. Fish are well known to be phenotypically plastic. Dieckmann and Heino argue that size will be plastic, because fish can decide when to mature, and if they mature earlier, they will be smaller (all other things being equal: if fisheries have strong density dependence, then fishing could increase growth rate!). Hence, the change in size may not be due to evolution: it could be that hard-wired behavioural cues are just kicking in at different stages of a fish's life.

Michaels7 wrote
"And more imporantly why can I take the same fish, breed it with better stock and produce larger, stronger, reproductive cycles? Because, they’re still the same ‘FISH’."

I don't understand why you're making a fuss about this: I haven't seen ANYONE argue that these papers show speciation, and can't see why anyone (at least any scientist or fisheries manager) would want to: they are only showing micro-evolution, but so what? It's still interesting, and of practical importance (because if there isn't evolution, then the stocks should rebound quicker if fishing is stopped).

Bob

I think Michaels7 is asking what the fuss is all about since the science of fishery management already understands how to manage the population through both selective breeding and population density. Just for kicks, since you seem convinced that "evolution" is slower than environmental cues about when (sizewise) to reach sexual maturity, how long does NeoDarwinian theory predict it takes these fish to "evolve" back to a larger size through selective breeding and how long it takes these environmental cues to acheive the same size increase. Surely you must have some clarification about how you know one should be faster than the other. -ds P.S. I can make your size a lot smaller here in about two seconds. -dt Bob OH
April 17, 2006
April
04
Apr
17
17
2006
10:14 PM
10
10
14
PM
PDT
Bob, this is a 'never ending story'. I stated this was 'micro-evolution'. Nothing more. No better examples exist than wildlife management as experimental evidence for farming of different fish species. Yes, Fish and Wildlife have done it as I said since before 1900. They had no choice due to overfishing in lakes and streams. If they did not "trout fishing in America" would've been history long ago. And yes they kept statistics. Some of them 'ole boys' even had college degrees Bob! They produced in reality, on a larger scale what this scientist did, but in opposite direction. Of course, they just saw it as a job in sustaining our wildlife resources, not as a highwater mark for Darwin and scientific arrogance. Its like herds of sheep or cattle overgrazing fields. It does not take government grants for scientific study on a patch of grass to understand to many sheep or cattle will turn a plush field into a barren wasteland. Small wars have been fought over these very issues. Again, science better serves us by making a hardier grass that can quicly recover itself under such strenous conditions. If the scientist in question was looking for ways to improve fish production that's different. But he was simply rediscovering well known facts and wasting money. "Note also that the story about the ranger isn’t about the response to selection: he was simply saying that larger fish produce more offspring (and I agree, of course we already knew that!)." Bob, this is not true, let me inform you my intentions. You just applied your lack of knowledge to my story. You're saying that a scientist because he took government money to do a study is smarter than typical Fish Hatchery personnel. First of all, maybe you should check the credentials of Wildlife management. My story is every bit as evidenturary as the scientist. One more time: 7th grade 4H club members understand selective breeding - step thru it - pick best of litter, mate with - ding - best from another line. Continue process until features of "best breed" are produced. This is what farmers do, cattle ranchers do, dog breeders do. Exactly what do you not understand? That people cannot figure this out without a scientific study? I gave you my reason for the problem. Demand and greed reduces the stock in the ocean. My point was that wildlife management of internal resources have long understood the impact of overfishing - and thus so to have nations and large commercial interest understood impact of overfishing the ocean. What we have solved on lakes and streams is harder to control worldwide between nations. If this is to straight forward, maybe we should take it to the UN.... ugh. They can reproduce another study whereby I am certain its America's fault fish are getting smaller ;-). My example story is simple, but do not mistake its simplicity for ignorance. It was not just about total reproduction - but quality reproduction. Throwing back larger fish denotes a stronger species to survive and reproduce. I guess only 'scientist' can recognize this in your opinion? Do you really think Fish and Wildlife did not understand breeding? Of course they did! Many of them grew up on farms! They knew that selectively throwing back large "keepers" would improve not just quantity, but QUALITY. Just because weekend angler JoeBillyBob did not understand the reason, does not imply Fish and Wildlife managers are stupid. Your argument is of arrogance and lack of historical undertanding of our nations resources. Why do you think there are limits on hunting bucks at times with certain number of points? They want a good stock to grow! Give people some credit, they're smarter than you think! "I’m confused about what you’re trying to argue. The original papers were demonstrating that there is evolution for earlier maturity and reduced size in fish. This is not the same thing as there being smaller fish: that’s not news, what was news was that there was actual evolution. i.e. they were showing that your statement “In the ocean, left alone, within a few generations, size, reproduction cycles will increase to normal” is wrong." Micro Bob - micro! Explain how the same fish can reproduce larger stock in a larger pond? Or smaller fish in smaller tanks? And more imporantly why can I take the same fish, breed it with better stock and produce larger, stronger, reproductive cycles? Because, they're still the same 'FISH'. Do you not understand the difference between quality of the genome and different species? Take any species and you derive multiple outcomes over time, but the fish is still a fish, whether weakened, small or not. This is no different than breeding dogs. It only proves one thing - again - variation. As I stated, I disagree. His study is to limited, inconclusive and naive. Secondly and more importantly, He "winnowed" out strong breeders and got weak stock. So what? Exactly my point there is no news here. He is doing exactly opposite of breeders for best breed. The only evolution taking place is MICRO. Given only a few of his weak stock mixed with good stock in wild conditions, they quickly replenish themselves with healthy, vibrant stock. If this was NOT TRUE, our lakes, streams and rivers would never replenish with good stock Bob. Sometimes lakes go thru periods of 'catch and release' to replenish the entire stock. This is different from quality limits. This study was and is a waste of money, better used for study of real problems we face in the future for ocean farming. "P.S. “It would be more useful to help fish farms in the ocean …” Just think how large the cages would have to be!" Bob, why should I imagine? Its already being done! See following story: http://www.npr.org/templates/story/story.php?storyId=5291579 Fish Farming has been going on for several years off northwest and northeast coast, and England. There are real problems, parasites being one I mentioned which can effect the wild fish population. We must solve these issues as the ocean cannot support a growing world population. It will not be enough to just build fish farms, we'll have to manage the runoff as well, just as we do with our own refuse. Otherwise the ocean will not survive for long with such large fish farming systems. We know this due to other large breeding systems such as hatcheries, chicken, pigs and cattle. Again, this does not take science to recognize it, but common sense and experience. Where science and engineering help is in designing systems to reduce the problems of refuse, to organically turn it into matter which can be beneficial for future use. That is where tax dollar are better spent. Not in 'rediscovering' the obvious. Science can address real issues. But I or any one with simple fishing knowledge could've told you long, long ago, not to take all the Big Ones! And despite the scientist claims in a lab, reproductive rates can radically increase given breeding and opportunity. He did not create a new species, only a weakened version, which can be easily replenished.Michaels7
April 17, 2006
April
04
Apr
17
17
2006
12:26 PM
12
12
26
PM
PDT
"My better half renewed my subscription as a Valentine day gift. So now I have to read the darn thing out of respect for her. Curses." This is easily atoned for via a contribution of equal or greater amount to the Discovery Institute, or ISCID.org with the receipt and an explanation sent to the editor of S.A.russ
April 16, 2006
April
04
Apr
16
16
2006
05:25 PM
5
05
25
PM
PDT

"This scientist learned what bass fishermen have known for decades. And what US Wildlife and Fish Hatcheries have known since before 1900."

Did the bass fishermen and 19th century US Wildlife and Fish Hatcheries workers really do the experiments, or did they just say "oh, fish are getting smaller". That can happen without selection: if you increase fishing effort, the average age and hence size will decrease.

Note also that the story about the ranger isn't about the response to selection: he was simply saying that larger fish produce more offspring (and I agree, of course we already knew that!).

Michaels7: I'm confused about what you're trying to argue. The original papers were demonstrating that there is evolution for earlier maturity and reduced size in fish. This is not the same thing as there being smaller fish: that's not news, what was news was that there was actual evolution. i.e. they were showing that your statement "In the ocean, left alone, within a few generations, size, reproduction cycles will increase to normal" is wrong.

Bob
P.S. "It would be more useful to help fish farms in the ocean ..." Just think how large the cages would have to be!

Smaller fish are still fish. And you've been caught, cleaned, and cooked. Hasta la vista, baby! -dt

I'll add that the whimpy fish are still Atlantic silversides and can still breed with the larger faster variety, so no macro evolution has taken place. I would even bet they all taste the same at the fish fry. -dmBob OH
April 15, 2006
April
04
Apr
15
15
2006
11:01 PM
11
11
01
PM
PDT
"Um, the whole point of the work was to demonstrate that there was a response to selection, i.e. that the populations evolved" Um Bob, "the whole point of the work" is a complete waste of money and probably our tax dollars. Doug you're right on target. This scientist learned what bass fishermen have known for decades. And what US Wildlife and Fish Hatcheries have known since before 1900. As a child going fishing we had limits on quantity and quality. Utilizing smaller resources on a lake, we had to conserve. Fishing limits changed to work with fluctuation of fish population levels and variety - including size. Yes, exactly, they asked us to throw larger ones back at times precisely because they knew over-fishing like "selective breeding" can be beneficial or harmful. Doug, you deserve a grant! Sign me up too! Micro-evolution, size variation - yes, but not macro. Talk about "Much ado about Nothing." Much as Woody Allen talks repeatedly about sex, scientist discover anew, selective breeding results in..., well, selective species. Neither Woody or Darwinist seem to learn from the past except its easier to fool the inexperienced. I am increasingly made more aware of studies produced for no purpose whatsoever. Wasting money for someone who does not understand nature or they've never experienced it first hand. Commercial fishermen have known since extinction of certain whales an inexhaustible food supply does not exist in our oceans, despite T.H. Huxley's proclamation to the contrary. Most nations are greedy in ocean harvesting and many refuse cooperation in limits. 7th grade 4H students understand 'selective breeding'. We didn't need a new study to tell commercial industry what it knows. The problem is not lack of knowledge, but demand between nations and greed of commercial interest. I predict his study is flawed on recovery analysis due to in-house lab - it does not mimic accurately ocean surroundings. In the ocean, left alone, within a few generations, size, reproduction cycles will increase to normal. Like Darwin's finches whose beak size returned to normal this is Dead News On Arrival. Tomorrow I look forward to eating Tilapia, probably from a fish farm in South America run by someone who is making a difference for our future. He didn't need a study, nor a grant, only a creative idea and careful observation of nature's truths long known by those close to it. Maybe that's a little harsh. But for this particular study, what a waste of money, time and resources. It would be more useful to help fish farms in the ocean to study such things as parasites and inhibitors to long term solutions for ocean farming. We already know what selective breeding does to a species. Why are scientist still surprised when they spend government money to produce it in a lab?Michaels7
April 15, 2006
April
04
Apr
15
15
2006
09:16 PM
9
09
16
PM
PDT
Um, the whole point of the work was to demonstrate that there was a response to selection, i.e. that the populations evolved. It's difficult to talk about evolution to the public without mentioning Darwin: it should really be a Fisherian debt, as the model for this sort of change comes from R.A. Fisher. And yes, it is evolution: it's a heritable change over time. Dang, that Fisher pun's so bad, I'll have to get it into the literature. BobBob OH
April 15, 2006
April
04
Apr
15
15
2006
11:05 AM
11
11
05
AM
PDT
I didn't renew my subscription to SciAm in November to protest the butthead editor-in-chief John Rennie's calling for universities to refuse admission to kids from Kansas as a warning to any other states who would do such a despicable thing as allow criticism of natural selection in a science class. My better half renewed my subscription as a Valentine day gift. So now I have to read the darn thing out of respect for her. Curses. ;-)DaveScot
April 15, 2006
April
04
Apr
15
15
2006
10:02 AM
10
10
02
AM
PDT

Leave a Reply