New study suggests polar bears evolved earlier than previously thought

Apr 20, 2012 by Lin Edwards report
polar bear

(Phys.org) -- A new genetic analysis carried out by and international team of scientists has revealed that polar bears and brown bears may have diverged around 600,000 years ago, which is much earlier than the previous estimate of 150,000 years ago.

The researchers were led by Frank Hailer of the Biodiversity and Climate Research Centre in Frankfurt, Germany (a joint venture between Senckenberg Nature Research Society and Goethe University). The team analyzed the nuclear DNA of 45 bears, including polar bears (Ursus maritimus) (Ursus arctos) and (Ursus americanus).

is passed down through both parents. Previous estimates of the emergence of polar bears as a discrete species were mostly based on the analysis of the smaller , which is inherited only through maternal blood lines.

The researchers compared 9,000 base pair sequences from the DNA of the 45 bears, and were able to use the data to construct a family tree, with the bears having greatest genetic difference being furthest apart on the tree. This allowed the scientists to estimate when the polar and brown bears diverged into separate species.

The results suggested that polar bears emerged around 600,000 years ago, which would mean the species has already survived several and inter-glacial warm periods. Hailer said this also makes sense because during that period the was much larger than at present, and so a greater area of suitable habitat was available for polar bears.

A lack of in the polar bear population also suggested that many polar bears died during the interglacial warm periods, creating a “genetic bottleneck,” and reducing genetic diversity.

Dating the emergence of polar bears as a separate species at 600,000 years ago rather than 150,000 years ago solves the problem of the appearance in polar bears of a number of specialized features, which would require a particularly rapid evolution if the shorter period was correct.

Hailer said he had long been puzzled by the idea that polar bears were such a rapidly evolving species and had wondered if it was true. He said the earlier studies using the mitochondrial genome and suggesting a divergence 150,000 years ago might have reflected a “hybridization event” during the last inter-glacial warm period, when polar and brown bears came into contact and bred during a period of melting sea ice.

This period would have introduced mitochondrial DNA from brown bears, and this could have given the hybrids a survival benefit. The population of at the time was small, and it is possible that in all the survivors the brown bear mitochondrial DNA had replaced the original polar bear mitochondrial genome.

The paper is published in the April 20th edition of Science.

Explore further: Fruit colours evolved to please picky birds, study says

More information: Nuclear Genomic Sequences Reveal that Polar Bears Are an Old and Distinct Bear Lineage, Science 20 April 2012: Vol. 336 no. 6079 pp. 344-347. DOI: 10.1126/science.1216424 . www.sciencemag.org/content/336/6079/344.short

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Salvador_Ramirez
1 / 5 (8) Apr 20, 2012
Okay 600,000 - 150,000 = 450,000 years...any difference here? :)
How much is the planet warming up in the last 450,000 years?
The end of human kind according to scientists that claim they can read the Maya calendar is 2012. Do they mean 2012 or 452,012?
Peteri
5 / 5 (4) Apr 20, 2012
@Ramirez
What on earth are you rambling on about?
kevinrtrs
1.3 / 5 (19) Apr 20, 2012
Hailer said he had long been puzzled by the idea that polar bears were such a rapidly evolving species and had wondered if it was true.

What the researcher is lamenting here is that the mitochondrial deterioration is incredibly rapid whilst the supposed uplifting and new complexity forming lucky mutational fixes are far too few or even none-existing whatsoever. This creates the conundrum that it would appear that bears must really have been in existence for only a very short time in more or less the same form that they appear now. OR ELSE - they had to have started out long ago and changed radically somewhere along the line, wiping out some important mitochondrial changes. He chose to assume the latter scenario.
Lurker2358
1.3 / 5 (14) Apr 20, 2012
Why, just a few weeks ago, they found a beetle which had the same DNA as it's own gut bacteria, which shows what everyone here has known and admits, which is to say, horizontal gene transfer can happen even across different kingdoms and phylla, but it is hard and probably involves a virus or prion or accident most of the time.

But the important thing to notice is that the gene transferred from the bacteria was not "accidentally created" through a mutation event. The entire gene was in fact designed in a special way, allowing it to modularly move between genomes, and neatly implant itself in the bug's genome. Quite a different scenario from the alleged "random accident creates a new super-gene" that evolutionists want everyone to believe in.

The biggest adaptation polar bears actually have is white fur.

If you could genetically modify polar bears to be black, and black bears to be white, and then swap environments, I bet they'd both be fine...
Sinister1811
1.9 / 5 (9) Apr 20, 2012
Interesting. What's also interesting is that Polar Bears and Brown Bears can interbreed.
ryggesogn2
1.6 / 5 (13) Apr 20, 2012
"The polar bears will be fine". Freeman Dyson
Yellowdart
3.2 / 5 (9) Apr 20, 2012
The biggest adaptation polar bears actually have is white fur.


Ummm they have translucent fur. It is actually pigment free. The skin underneath is also black.
NotParker
1.6 / 5 (14) Apr 20, 2012
Typical AGW con game. Blaming interglacials for killing bears that hunt from land. The only problem polar bears have today is that over 1000 are shot each year.
ryggesogn2
1.7 / 5 (11) Apr 20, 2012
The biggest adaptation polar bears actually have is white fur.


Ummm they have translucent fur. It is actually pigment free. The skin underneath is also black.

Except in zoos when algae turns them green.
TheGhostofOtto1923
2.3 / 5 (9) Apr 20, 2012
The biggest adaptation polar bears actually have is white fur.


Ummm they have translucent fur. It is actually pigment free. The skin underneath is also black.
Whiteness as camouflage is common and the adaptive potential must have developed early in evolution. Many species at White Sands in NM, a relatively small area, are white-adapted, including insects, spiders, scorpions, lizards, mammals, and even toads.
http://www.nps.go...ands.htm
TheGhostofOtto1923
1.7 / 5 (6) Apr 20, 2012
But the important thing to notice is that the gene transferred from the bacteria was not "accidentally created" through a mutation event. The entire gene was in fact designed in a special way, allowing it to modularly move between genomes, and neatly implant itself in the bug's genome.
As always speedball thanks for the link. Gene transfer among species is common. Some species are actually an amalgam of different, independent species, such as lichen, which evolved tofether.
http://en.wikiped...transfer
Torbjorn_Larsson_OM
3.9 / 5 (11) Apr 20, 2012
That is good news for polar bear survivability. The ice age (Pliocene -Quaternary glaciation) is ~ 2.6 billion years, and surviving such a long period with some 10 interglacials shows robustness.

@ kevintrs:

"What the researcher is lamenting here is that the mitochondrial deterioration".

No, he is not, as an even cursory reading of the article shows. A biologist wouldn't claim something that isn't observed in nature. Instead he discusses how evolution changes species.

Creationists shouldn't comment on science sites.

@ Lurker2358:

"The entire gene was in fact designed in a special way, allowing it to modularly move".

You are confusing cause and effect by selection bias, as those genes that can't move - can't move. This is called evolution, and is known to result in functionality.

Creationists shouldn't comment on science sites.

@ NotParker:

Nobody mentioned AGW, the accepted climate science theory, until you did.

Climate denialists shouldn't comment on science sites.
ryggesogn2
1.9 / 5 (14) Apr 20, 2012
Climate denialists shouldn't comment on science sites.

Scientists can't tolerate dissent.

"A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.
Max Planck"
Read more at http://www.brainy...dwxXH.99

NotParker
1.7 / 5 (12) Apr 20, 2012
Nobody mentioned AGW, the accepted climate science theory, until you did.


Reuters did:

"The finding suggests polar bears took a long time to adapt to their icy world and may therefore struggle to adjust as the Arctic gets warmer and the sea ice melts, depriving them of vital hunting platforms."

http://uk.reuters...20120419

Don't be dupe. The whole point of this study is to get them to try and think Polar Bears are endangered because of AGW, when it is hunters shooting them that causes problems.

BBC too:

And the AUthors:

"Writing in Science, they explain: "Although polar bears have persisted through previous warm phases, multiple human-mediated stressors (eg habitat conversion, persecution, and accumulation of toxic substances in the food chain) could magnify the impact of current climate change, posing a novel and likely profound threat to polar bear survival."

http://www.bbc.co...ronment-
NotParker
1.4 / 5 (11) Apr 20, 2012
Nobody mentioned AGW, the accepted climate science theory, until you did.


The authors did:

"The researchers say polar bears face many other threats to their survival today, including habitat destruction, hunting and the effects of environmental pollutants.

Writing in Science, they explain: "Although polar bears have persisted through previous warm phases, multiple human-mediated stressors (eg habitat conversion, persecution, and accumulation of toxic substances in the food chain) could magnify the impact of current climate change, posing a novel and likely profound threat to polar bear survival.""

http://www.bbc.co...17762196
MandoZink
5 / 5 (3) Apr 20, 2012
The biggest adaptation polar bears actually have is white fur.


The fur is not white. Polar bear hairs are actually transparent. They have no pigment. The hairs also do not absorb UV and do not allow IR to pass through, keeping them warm. The military has studied polar bear fur because it masks IR. Except for its breath, you cannot see a polar bear with infrared devices. It is an excellent evolutionary development for the far northern latitudes.

Horizontal gene transfer does occur. And gee whiz, I had no idea genetic engineers had "designed" those similar gene segments. I guess I need to spend some time unlearning genetics and dumping evolution since I can just put "god in the gaps". NOT!
Vendicar_Decarian
0.6 / 5 (41) Apr 21, 2012
That is Alzheimer talking there Tard Boy.

""The polar bears will be fine". Freeman Dyson" - RyggTard
Vendicar_Decarian
0.8 / 5 (43) Apr 21, 2012
We generally abhor liars. That is why very few scientists are Conservatives or RandTards.

"Scientists can't tolerate dissent." - RyggTard

http://www.woodfo...dcrut4gl
Skepticus
3 / 5 (10) Apr 22, 2012
Who cares if polar bears evolved earlier than thought? It is a proven fact here, reading from this forum, that homo stupidus is breeding out of control, and haven't evolved a single bit.
NotParker
1 / 5 (8) Apr 22, 2012
Polar Bears are fine


Except for the 1000 or so shot each year.

http://pbsg.npola...ml#faq14

okyesno
1 / 5 (5) Apr 23, 2012
So how did the first polar bear emerge? The article offers no answer. Pushing back the date 450,000 years doesn't explain anything but just increases the mystery. The speculative branching off event is still without any form of proof.
Ethelred
3 / 5 (6) Apr 23, 2012
So how did the first polar bear emerge?
Moved North as a brown bear and those in the North adapted via the normal evolutionary process as they were no longer interbreeding with bears that were better off brown than white.

Mutations happen. This is a fact. Failure to reproduce happens and that is a fact. Those two cannot not result in evolution and given time an separation, speciation. It would take a miracle to stop it from occurring. Be a nasty miracle as then the bears would have to stop moving into the North. Not quite as nasty as an intelligent psycho designer would have to be to create parasites. It would take a John Wayne Gacey to design parasitic wasps.

Ethelred
Yellowdart
1 / 5 (8) Apr 23, 2012
Moved North as a brown bear and those in the North adapted via the normal evolutionary process as they were no longer interbreeding with bears that were better off brown than white.


So brown bears moved north...and somehow figured out they needed to have web feet and translucent fur, while standing on white snow with the capability of preventing water from freezing in their hair post swim? Rate of reproduction and loss of offspring does not bode well for speciation when it comes to polar bears.
okyesno
1.4 / 5 (10) Apr 23, 2012
So a bunch of brown bears move north, and suddenly in one (?) bear a mutation occurs that happens to change the fur just right and happens to be just what is required out there, and by some one in a million stroke of luck was retained and copied into the entire future population. Very implausible.

More likely, the genetic capability to adapt to a colder and sunny climate was already present in the DNA. This capability was activated because of environmental pressure. Just as the longer beaks were activated in Darwin's finches. Once the finches were taken out of the habitat, the beaks changed to normal size back again. The question is then: how are these genetic variations pre-programmed into the original DNA?
Deathclock
2 / 5 (8) Apr 26, 2012
So a bunch of brown bears move north, and suddenly in one (?) bear a mutation occurs that happens to change the fur just right and happens to be just what is required out there, and by some one in a million stroke of luck was retained and copied into the entire future population. Very implausible.


The problem with you anti-evolution retards is that you think everything happens with ONE mutation in ONE individual... The same mutations occur CONSTANTLY, or do you think only one human has ever been born with sickle cell anemia? It's likely that in the original brown bear population some bears were born with slightly lighter fur ALL THE TIME... it wasn't advantageous and so it wasn't selected for UNTIL they migrated to the arctic. After that, bears with SLIGHLY lighter fur were selected for, and the average color of the fur got lighter and lighter over MANY generations.

Stop talking, your ignorance is showing.
Deathclock
1.6 / 5 (7) Apr 26, 2012
So brown bears moved north...and somehow figured out they needed to have web feet and translucent fur?


What I said above goes for you as well.
Yellowdart
1 / 5 (7) Apr 26, 2012
What I said above goes for you as well.


Except I made no such comments about needing one mutation in one individual. The fact you would need multiple over many generations creates a bigger problem, not a smaller one.

Once again, you'd have to overcome the rate of reproduction and loss of offspring verses the harsh climate. Similar mutations like sickle cell aren't beneficial. Mutations have no awareness of the fact you are standing on white snow now.

True, that a brown bear population could have lighter fur representations, but polar bear fur isn't just lighter, it's entirely hollow/translucent. Are you suggesting that brown bears were self aware enough to know that they needed to only sleep with the rare white bears if they were going to live on the snow? And even if they did, their genetics wouldn't guarantee that outcome, being the minority. Polar bears need web feet and their fur from within a few generations at most. Nature doesn't wait on you.
Deathclock
2 / 5 (8) Apr 26, 2012
What you've stated and how evolution actually functions have nothing in common... I don't even know where to go with you short of telling you to go back to school, I'm not in a position to teach you evolutionary theory from the ground up in 1000 characters or less here.
Yellowdart
1 / 5 (6) Apr 26, 2012
What you've stated and how evolution actually functions have nothing in common... I don't even know where to go with you short of telling you to go back to school, I'm not in a position to teach you evolutionary theory from the ground up in 1000 characters or less here.


How else would it function? All I did was echo what you said, and then asked how it would know what to select for and how it would over come the rate of death? Polar bears currently lose 70% of their young and don't produce more than 2 typically.

If you subject a population of ancestor brown bears to the harsh arctic via a population split, the death rate would be higher back then than 70% when few would have been capable if any.

You could easily test this now, take 1000 brown bears, drop them on the arctic ice. See which fit survive.

Deathclock
2.6 / 5 (10) Apr 26, 2012
You could easily test this now, take 1000 brown bears, drop them on the arctic ice. See which fit survive.


Is that what happened originally? Were the brown bears airlifted to the arctic? Or, did they slowly migrate northward over time?

Tell me, is there a latitude where everything south is green and everything north is white?

No, of course not, and of course the bears did not migrate thousands of miles in a day. They migrated slowly, and as they did the landscape got progressively more white and less green...

When you consider these things in terms of the REAL WORLD, you will see where your objections fail.
NotParker
1 / 5 (4) Apr 26, 2012
"Ursus maritimus tyrannus was a very large fossil subspecies of polar bear, descended from an Arctic population of brown bears. Its name in Latin means tyrant sea bear. The species is mentioned by Björn Kurtén, who assigned it to a polar bear subspecies, U. m. tyrannus.[1] Its bones have been found in England."

Wait!

"U. m. tyrannus was the first polar bear and evolved sometime in the Middle Pleistocene. While the oldest fossil is 70,000 years old"

England? Oldest fossil only 70,000 years old. First Polar Bear?

http://en.wikiped...tyrannus
Yellowdart
1 / 5 (6) Apr 26, 2012
Is that what happened originally? Were the brown bears airlifted to the arctic? Or, did they slowly migrate northward over time?


It could be either, but a slow migration means that they would still be well suited to a greener environment on their way north. Animals prefer their natural habitat. Birds fly south for the winter to similar habitats. In essence a brown bear population may migrate north, but it will stop short of anything intensely stressful, because there is no point in going farther.

It is when the population is split and cut off, forced into a drastically different environment that the need to be a polar bear (for instance) will arise. Right? If the grass is still green, you don't need translucent hair, web feet, or even deicing to live on green grass.

Yellowdart
1 / 5 (5) Apr 26, 2012
No, of course not, and of course the bears did not migrate thousands of miles in a day. They migrated slowly, and as they did the landscape got progressively more white and less green...


According to the wiki link Parker provided, the current theory is glaciation separated a small population. So was it migration or separation? However, a small population has even less chance of reproduction and surviving drastically worse conditions. It's far easier to migrate back south if possible, than to hang around on the ice where the environment isn't suitable.

When you consider these things in terms of the REAL WORLD, you will see where your objections fail.


The real world doesn't give you millions of years, or many generations. The real world kills a fish out of water. And when the isolated environments are similar they do not produce drastic changes, but small variations. That's the real world.
Deathclock
2.2 / 5 (10) Apr 26, 2012
In essence a brown bear population may migrate north, but it will stop short of anything intensely stressful, because there is no point in going farther.


FOOD!

If the grass is still green, you don't need translucent hair, web feet, or even deciding to live on green grass.


Newsflash: Bears do not eat grass. They eat meat. They will migrate where the food is. If they've overpopulated their niche such that they are starving they will migrate to find new game whether there is snow there or not.
MandoZink
5 / 5 (1) Apr 27, 2012
A bear walks 100 miles due south, then 100 miles due east, then 100 miles due north and ends up where he started.

What color is the bear?

Sorry, I always liked those curved space jokes.
Ethelred
3.2 / 5 (9) Apr 27, 2012
So brown bears moved north...and somehow figured out they needed to have web feet and translucent fur,
No it just evolved. No figuring was needed. Mutations that caused those things were kept and mutations that stopped them were lost.

Rate of reproduction and loss of offspring does not bode well for speciation when it comes to polar bears.
They already did that. Lots of them die still. Especially those with mutations that stop those things.

and suddenly in one (?) bear a mutation occurs that happens to change the fur just right and happens to be just what is required out there
No. Suddenly in one parent there was a mutation that stopped the production of pigment. Happens now on then in all species with pigment. Usually the individual in which that mutation is fully expressed fails to reproduce. BUT on snow it is a good thing and thus the individual WILL reproduce.>>
Ethelred
3.2 / 5 (9) Apr 27, 2012
and by some one in a million stroke of luck was retained and copied into the entire future population. Very implausible.
Well except for the nonsense about one in a million when the very first time it happens it would be a STRONG advantage it is very possible. Indeed inevitable.

More likely, the genetic capability to adapt to a colder and sunny climate was already present in the DNA.
Possibly but then we should see a lot of white grizzlies and we don't so you are wrong on that. As usual for you.

This capability was activated because of environmental pressure.
Except there is no such capabilty in brown bears.

Just as the longer beaks were activated in Darwin's finches.
No those evolved as well. Minor mutations in homeobox genes most likely.

Once the finches were taken out of the habitat, the beaks changed to normal size back again.
No. The mutations could be lost since they were in a new environment and they evolved to meet it.>>
Ethelred
3.2 / 5 (9) Apr 27, 2012
The question is then: how are these genetic variations pre-programmed into the original DNA?
The question is do you have any evidence that they were. There is no such evidence at present.

Now since Yellowdart already knows the Great Flood could not have happened how about if Henrik tries dealing with it. As in I just dealt with your questions about real theories lets see you deal my questions about your beliefs?

When was that Flood Henrik? Where is some evidence for it? Physical evidence, genetic evidence counts as physical.

Ethelred
Ethelred
3.4 / 5 (5) Apr 27, 2012
Newsflash: Bears do not eat grass. They eat meat. They will migrate where the food is.
Newsflash Deathclock. Brown bears eat things besides meat. So that is another area that polar bears have adapted to over time. They no longer eat berries and such things.

The rest of that was fine.

Ethelred
Ethelred
2.7 / 5 (7) Apr 27, 2012
So was it migration or separation?
Either way there is reproductive separation.

However, a small population has even less chance of reproduction and surviving drastically worse conditions.
Not drastically worse. Different, different food but lots of it that isn't ready for bears. Smaller populations evolve faster as mutations become a majority of the gene pool more quickly.

ice where the environment isn't suitable
Except that large bears are suitable. They can swim just fine in cold water and seals are easy targets for them. They likely didn't need to do much swimming early on.>>
Ethelred
3 / 5 (8) Apr 27, 2012
The real world doesn't give you millions of years, or many generations.
It frequently does but in this case it happened in tens of thousands of years which is thousands of generations. They are still bears, the main change was they lost hair pigment. A very simple mutation is all that is needed for that. ANYTHING that stopped the production of hair pigment does the trick. A small population of less than a thousand bears could all go white in less then a dozen generations after that mutation and any single mutation of MANY mutations would do the trick.

Webbed feet is no big deal either. WE have webbed hands and toes. Webbing is something that is LOST not gained. The seperation between fingers and toes is a matter of programmed cell death. Any mutation that decreases the cell deaths causes webbing.

Ethelred
Yellowdart
1 / 5 (6) Apr 27, 2012
FOOD!


Better food where they were. Difficult to hunt arctic seals without the proper equipment.

Newsflash: Bears do not eat grass. They eat meat.


Newsflash: Bears are omnivores. They eat both. Polar bears are fairly carnivorous considering the lack of plants in the arctic, but they will also eat kelp.

If they've overpopulated their niche such that they are starving they will migrate to find new game whether there is snow there or not.


Overpopulation has a tendency to result in diseases. Deer for example. They would only migrate to a similar environment, even in overpopulation. Birds fly south to similar environments rather than brave the cold, harsher winters. Other bears hibernate during winter for the most part. Animals avoid harsh conditions unless forced into them.

Yellowdart
1 / 5 (7) Apr 27, 2012
BUT on snow it is a good thing and thus the individual WILL reproduce.


This is poor reasoning Ethelred. If this is the case, then no species would ever go extinct just because it's a good thing and it MUST reproduce.

Stick to the science. Go through the various breeding studies done over the years, none of them show selections for mutations becoming a dominant trait, and especially in the outside world, the isolated mutant is an outcast never selected for.

Further, you are assuming that at least 1 individual had such loss of pigment, that another bear slept with it, AND it passed on such mutation to the offspring...all the while surviving the significant change in environment and available food source.

kaasinees
0.9 / 5 (28) Apr 27, 2012
Stick to the science. Go through the various breeding studies done over the years, none of them show selections for mutations becoming a dominant trait,

Wrong, liar, idiot!

http://blogs.scie...ication/
Yellowdart
1 / 5 (4) Apr 27, 2012
Webbed feet is no big deal either. WE have webbed hands and toes. Webbing is something that is LOST not gained.


Then revise the glaciation theory. I would agree with this, and it is more likely the case that say a polar bear can shift to being a brown bear, than vice versa. Considering the availability of a brown bear's food source and it's more temperate climate. In essence it would be much easier to lose the fur and webbed feet, than to gain them as it would have the time.

I don't believe there is any indication though that the current though of ancestor of polar bears and brown bears had webbed feet, much less individuals with hollow translucent hair.

Yellowdart
1 / 5 (4) Apr 27, 2012
Wrong, liar, idiot!


No reason to be insulting kass, simply providing the link is enough. I'm not sure what your point is. According to the article you provided:

The scientists initially theorized that adrenaline might share a biochemical pathway with melanin, which controls pigment production in fur. Further research has since supported this initial hypothesis.


This is a environmental effect from biochemical/adrenaline interactions. It's not mutation but natural selection. Physiological changes are there, but minor. Every breeder will tell you there are limitations on what you can do in breeding.
kaasinees
0.5 / 5 (24) Apr 27, 2012
The only limitation to breeding is TIME.
Fish can change organ structure pretty quickly in breeding programs.
In fact japanese koi are very hard to breed becuase you need to keep the right conditions so they dont change into more regular goldfish.

your ignorance Needs to be insulted, plain simple.
Yellowdart
1 / 5 (3) Apr 27, 2012
The only limitation to breeding is TIME.


This is incorrect. Time is one of the limitations. Genetics and natural selection also provide limitations.

In fact japanese koi are very hard to breed becuase you need to keep the right conditions so they dont change into more regular goldfish.


Your own ignorance is showing.

http://www.aquati.../koi.php

Koi goldfish are not a variation of the chinese goldfish. Both have been domesticated for centuries as well, and although they are both considered carp and close relatives breeding a koi poorly won't give you a goldfish. They can hybridize, but they are sterile offspring.
kaasinees
0.7 / 5 (26) Apr 27, 2012
And so i said REGULAR gold fish.
And i actually have a pond and meet with koi breeders.
I think i know what i am talking about, european kois are usually of bad quality and look more like regular gold fish than koi fish that have been properly taken care of becuase of a few generations of bad breeding.
I think we can both agree there is a difference between regular goldfish and a koi fish, even in physiology.
Yellowdart
1 / 5 (3) Apr 27, 2012
And so i said REGULAR gold fish.


You implied that poor breeding of koi results in a "regular" goldfish, not looks like one.

A "regular" goldfish is the species Carassius auratus auratus

A koi is the cyprinus carpio

Breeding poorly may give you a koi that looks like a goldfish ,but it doesn't give you Carrasius.

When you implied "regular" I assumed you meant Carrasius.

And yes I agree that bad breeding, or any breeding experiments can lead to physiological changes. Look in the variation in humans just for that alone. No matter how many times you breed koi though, you still get koi of some variety. Given limitless time and breeding, that's all you will ever get. You won't get an actual "regular" goldfish or anything else for that matter. But you are welcome to try.

Ethelred
2.3 / 5 (3) Apr 30, 2012
Better food where they were
That is an assumption. I don't think it is correct. Not if the bears population had expanded recently.

Difficult to hunt arctic seals without the proper equipment.
Bears have that equipment. Especially in the summertime. So it is likely they started out in the North just in the summer.

but they will also eat kelp.
Hey I may have learned something. Cool. Is there much kelp up there? Sure is along the coast of California and the water is pretty cold. Just not that cold.

Overpopulation has a tendency to result in diseases.
Only if they don't migrate.

They would only migrate to a similar environment, even in overpopulation.
Which is not the case for the ancestors of polar bears.

Animals avoid harsh conditions unless forced into them.
Which is what overpopulation does. Dears don't move north because there are other species of dear and reindeer up North already.>>
Ethelred
3.4 / 5 (5) Apr 30, 2012
This is poor reasoning Ethelred.
Not just because you say so.

If this is the case, then no species would ever go extinct just because it's a good thing and it MUST reproduce.
No and I did imply that. Loss of pigment is frequent mutation. In less northern areas it gets selected OUT. In the snow it is conserved. Don't try to change that something else entirely.

Stick to the science.
I did. You either failed to understand or distorted it.

none of them show selections for mutations becoming a dominant trait,
Oh that is horse manure. Completely false.

I have been on Yahoo a bit and it sure is nice that I can post links showing EXACTLY how this wrong.

http://myxo.css.msu.edu/ecoli/

http://en.wikiped...periment

>>
Ethelred
3.4 / 5 (5) Apr 30, 2012
Around generation 33,127, the experimenters noticed a dramatically expanded population-size in one of the samples; they found that there were clones in this population that could grow on the citrate included in the growth medium to permit iron acquisition. Examination of samples of the population frozen at earlier time points led to the discovery that a citrate-using variant had evolved in the population at some point between generations 31,000 and 31,500.


The mutation became VERY dominant.

And Richard Dawkins covers that in the Greatest Show On Earth.

the isolated mutant is an outcast never selected for.
Nonsense. If it increases reproduction as the citrate mutation OR white fur does then that is EXACTLY what will selected for.>>
Ethelred
3.4 / 5 (5) Apr 30, 2012
Further, you are assuming that at least 1 individual had such loss of pigment, that another bear slept with it
Since they have white fur it is a very reasonable assumption. To assume otherwise is to assume magic and that isn't needed here. Pigment loss is a frequent mutation in many species. Us too.

.all the while surviving the significant change in environment and available food source.
All the while taking advantage of the new uninhabited environment. That is uninhabited by competitors that have white camouflage or other bears.

hen revise the glaciation theory.
Why?

and it is more likely the case that say a polar bear can shift to being a brown bear, than vice versa.
Not in the Arctic. It is the environment that does the selection.

Considering the availability of a brown bear's food source and it's more temperate climate.
Again that is irrelevant in the Arctic.>>
Ethelred
3.4 / 5 (5) Apr 30, 2012
In essence it would be much easier to lose the fur and webbed feet, than to gain them as it would have the time.
No. The pressure of DEATH drives things the other way. Much harder to compete with other bears than to move where they aren't once the bears get any edge in the Arctic. White fur is a good edge. THEN the web feet starts to be selected for.

I don't believe there is any indication though that the current though of ancestor of polar bears
Sure there is. They exist today. They did not exist in the past. Since we KNOW that evolution can and does occur there is no need to invoke magic for an answer.

much less individuals with hollow translucent hair.
Translucent is just a loss of pigment. Hollow, well that one I don't know enough about but all the rest I gave solid reason for. I think hollow hair wouldn't take a lot of change. Quite a few species have evolved hollow hair.>>
Ethelred
3 / 5 (4) Apr 30, 2012
Every breeder will tell you there are limitations on what you can do in breeding.
Over short periods of time. Mutations hit in every generation and in darn near every single individual.

This is incorrect. Time is one of the limitations.
It is THE significant one for breeders.

Genetics and natural selection also provide limitations.
Breeders generally control the environment enough that natural selection isn't much of a limit in comparison to time. Mutations are the genetic key and it takes time to get a large number of significant mutations ADDED to the natural gene pool. In human selected populations mutations that would be fatal or serious can be maintained if the breeder wants it badly enough. The short noses and anti-survival hair of Persian cats exist entirely due to breeder intercession with natural selection.>>
Ethelred
3 / 5 (4) Apr 30, 2012
Given limitless time and breeding, that's all you will ever get.
Nonsense. That is an assumption of a magic intervention. Given limitless time speciation will occur if any effort is put into it. All that is needed is a effort to make one group have a characteristic that incompatible with another group. A change in breeding season will do the trick for sure.

Ethelred
okyesno
1 / 5 (8) Apr 30, 2012
The breeding of animals shows two major facts: 1. you cannot make a non-dog out of a dog, no matter how many generations. 2. introducing new species requires intelligence and weeds out mutants. Both results are evidence against Darwin.
Ethelred
3.3 / 5 (7) Apr 30, 2012
1. you cannot make a non-dog out of a dog, no matter how many generations.
False. No one has tried and no one has breed dogs long enough.

2. introducing new species requires intelligence
False. Reproductive separation and sufficient not intelligence is what is needed. Selection is selection whether by men or by the environment.

and weeds out mutants.
Or selects to keep them. Such as the e-coli I linked to.

Both results are evidence against Darwin.
Utter fabrication based on two separate fabrications.

Go read the e-coli experiment. Then try reading Richard Dawkins The Greatest Show On Earth.

Now where is that evidence for a Young Earth and the Great Flood?

If you can't post I will have to assume you agree that there was not Flood and Bible is just the writing of fallible men.

Ethelred
okyesno
1 / 5 (9) Apr 30, 2012
The e-coli expermiment just confirms my assertion that it takes an expensive lab and smart scientists to even change the DNA this much. Furthermore, the DNA code that allowed the citrus utilization was likely already present in the genes. Wild e-coli are known to have this ability. In the end however the e-coli remained very much what it was: an e-coli.

As with dogs, all the breeding so far has proven that dogs (canus)remain dogs. That observation does not support Darwinism. To say that the time was not long enough is arbitray and unscientific hubrus.
Ethelred
3 / 5 (6) Apr 30, 2012
The e-coli expermiment just confirms my assertion that it takes an expensive lab and smart scientists to even change the DNA this much.
Horseshit. It takes a lab to DOCUMENT it and meet the demand for the lab evidence that Creationists claim doesn't exist. That was very typical of you. Demand evidence and then lie about.

Furthermore, the DNA code that allowed the citrus utilization was likely already present in the genes.
Read the site. It was not. It took TWO mutations at that.

Wild e-coli are known to have this ability.
Really. Go ahead and produce evidence. In any case only ONE of twelve sets adapted so you are wrong about this set.

In the end however the e-coli remained very much what it was: an e-coli.
And still evolved by mutation and natural selection.

As with dogs, all the breeding so far has proven that dogs (canus)remain dogs.
And no one has tried to produce something else.>>
Ethelred
3 / 5 (6) Apr 30, 2012
. That observation does not support Darwinism.
Lie. It certainly does. It fits exactly. Mutation followed by selection by the environment. Humans did NOT make the selection in the E-coli.

To say that the time was not long enough is arbitray and unscientific hubrus.
Lie. It takes many generations and dogs have only been actively breed since the 1700's and that was by the Brits. Not once has anyone tried to create a new species. HOWEVER we humans are a new species. Flying squirrels are in middle of changing KIND and FRUIT BATS have already done so.

Now about the Great Flood, where is some physical evidence for it oh incompetent evader?

Since you seem unable to even acknowledge the question that is a clear indication that you are fully aware that there is such evidence. Which means you know you are shoveling crap here as the Bible is disproved by the lack evidence.

Of course you could be the first to produce such evidence.

Ethelred
okyesno
1 / 5 (8) Apr 30, 2012
Barry Hall, Chromosomal Mutation for Citrate Utilization by Escherichia coli K12, Journal of Bacteriology 151 no. 1 (1982) 269273

Citrus use in e-coli is nothing new, and bacteria have to ability to change back and forth. This is simply a flexibility already programmed into the DNA. Lenski's reasearch is a dud.

You have no idea how much people have tried to re-engineer dogs for specific purposes. This simply proves that a breeders skill combined with information already present in canis produces these results, not some imiginary randomness you silly boy.
Yellowdart
1 / 5 (2) May 01, 2012
That is an assumption. I don't think it is correct. Not if the bears population had expanded recently.


Thinking it's incorrect is an assumption as well. Current theory on polar bears doesn't promote overpopulation either.

Bears have that equipment. Especially in the summertime. So it is likely they started out in the North just in the summer.


If it's summertime, then the food/environment aren't harsh nor relatively any different. They'd have no reason to go after more difficult food or habitats. Even overpopulation is only going to create a problem if it generates a lack of food source. Deer are overpopulated because there's plenty of food and regular habitat.

Dears don't move north because there are other species of dear and reindeer up North already


Why, do they call ahead to see if there's a vacancy?
Yellowdart
1 / 5 (4) May 01, 2012
In less northern areas it gets selected OUT. In the snow it is conserved.


I'm not sure if I get you here, there's usually more snow in the north. Reindeer aren't white, nor do they have translucent fur.

I have been on Yahoo a bit and it sure is nice that I can post links showing EXACTLY how this wrong.


You mean citrate as a source of food? It occurred once in a trillion cells according to your links. That's not dominant. And E.coli has always had the enzymes to do so, but does not readily do it unless under low oxygen levels. Other work has been done on this by Klaas and Hall in their respective studies.

Further, that's a lab, with 30,000 plus generations. You really wish to compare that to polar bears? They don't get 30,000 generations to adapt to the arctic winters if they become isolated.
Yellowdart
1 / 5 (3) May 01, 2012
It is THE significant one for breeders.


Great, wonderful, doesn't mean it's the only.

Mutations are the genetic key and it takes time to get a large number of significant mutations ADDED to the natural gene pool.


Did you read the E.Coli study? He had 10-20 at most that he considered beneficial out of his millions. At most 100 good/neutral, AND in a controlled environment. That's weak sauce.

Nonsense. That is an assumption of a magic intervention. Given limitless time speciation will occur if any effort is put into it.


You don't have limitless time in nature. Assuming you do is a magical intervention.
Yellowdart
1 / 5 (3) May 01, 2012
No one has tried and no one has breed dogs long enough.


Assumption.

No one has seen God either, but one day! (Also assumption)

Current study after study of breeding only results in dog begetting dog. There are tons of variations, species, and diversity of dogs via mutation, speciation, and natural selection, but when you reproduce them, all you get is another dog. It's defined by the vary range of genes involved and thus limited. ANd if you think it only started in the 1700s with domesticating/breeding dogs then you should do some more reading.

Humans did NOT make the selection in the E-coli.
Nope they didn't, because it was already there. They did force the change in environment and thus forced adaptation. It's as much artificial selection as breeders when attempting to select certain traits.
Yellowdart
1 / 5 (4) May 01, 2012


Not once has anyone tried to create a new species.


Maybe you are just exaggerating, but honestly, any breeding attempt should have the potential to produce a new species, intently trying or not, thus it has been tried since man has in the least been breeding animals. And as far as lab attempts go, you should honestly spend some time researching the history.

In fact with recent fly studies of 600 generations, they couldn't even prove fixated mutations. Your talking 12,000 years compared to us. See Burke, Nature - UCI

Study after study continues to show as well that if you breach certain limitations on genetic alterations/mutations the species will die.

Quit reading the community spin, read the studies yourself. Examine the history. You can't get birds from dinos with DNA no matter how much time. It won't let you.
Yellowdart
1.6 / 5 (7) May 01, 2012
Now about the Great Flood, where is some physical evidence for it oh incompetent evader?

Since you seem unable to even acknowledge the question that is a clear indication that you are fully aware that there is such evidence. Which means you know you are shoveling crap here as the Bible is disproved by the lack evidence.


Maybe it just needs more "time" too? Eh? Eh?

Not speaking for okeysno, but your welcome to PM me if you wish to discuss the Bible. It's off topic, and frankly, the redirection by you lends little to your argument, esp if you believe the Bible has no bearing on science.

This is like asking for historical evidence of the Battle of Gettysburg while trying to prove an argument on gravity. And even if you are wrong on one, it doesn't disprove the other.