I am Inducing Metamorphosis in Axolotls and Documenting the Process

[curtpw]

The metamorphosis of captive axolotls may very well be the most controversial and misunderstood issue amongst salamander hobbyists. I have been both frustrated and intrigued by the sheer volume of casually voiced opinion that is clearly contradicted by scientific evidence. Being both a research engineer and a salamander lover, I feel an experiment is in order.

Once it gets a little cooler (probably November, my NYC apartment doesn't allow for great temperature control) I will purchase six or so adolescent axolotls and manipulate their environment and diet in a fashion that induces metamorphosis. My goal is to avoid thyroxine or iodine but in my opinion, the use of thyroxine to induce metamorphosis is perfectly ethical - it just isn't that interesting.

METHODS:
1) Lowered water level.
2) Periodic fasting.
3) Artificial extended lighting (grow lights).
4) Mechanical water agitation (tank sits on top of 4 timers controlled vibration motors.

OPINIONS TO BE INVESTIGATED (I will briefly editorialize, but these will be addressed with literature citations once I start the project)

1) Axolotls are not 'meant' to morph, do not 'naturally' morph or are not 'happy' morphing: If Axolotls were not meant to naturally morph they wouldn't have the ability to do so. Evolution is a powerful force. If a complex and energy-intensive trait like metamorphosis were not useful it would in all likelihood be eliminated from the gene pool.

2) Axolotls do not naturally undergo metamorphosis so any morphed Axolotl you see is probably a Thyroxine induced morph: Not only is natural metamorphosis possible, everything I've read points to it being fairly easy - just not under the conditions under which most hobbyists care for their animals. 10% of the entire USA lab stock population of Axolotls underwent spontaneous natural metamorphosis because of a 3-hour truck ride: https://www.quantamagazine.org/axolotl-genome-slowly-yields-secrets-of-limb-regrowth-20180702/

3) Inducing metamorphosis in Axolotls is cruel and/or unethical: But keeping wild animals like Axolotls in a tank (how is that for 'natural'?) for personal entertainment is fine, right?..... I am doing this out of scientific curiosity, but even if I was doing this for fun or profit, so what? Getting Axolotls to undergo metamorphosis is a lot of work, no one is going to do it out of cruelty or neglect. Also, Axolotls can be captive bred but Tiger Salamander can't! All pet Tiger Salamanders are wild caught. What if instead of taking Tiger Salamanders out of the wild many hobbyists kept captive bred morphed Axolotls instead? The induction of metamorphosis in Axolotls has obvious value when it comes to advocacy for captive breeding of pet terrestrial salamanders. Also, it is worth mentioning that Axolotls are an extremely valuable animal model for research in regenerative medicine. Some of this research really is cruel (cutting off limbs, removing skin etc.) and as a salamander enthusiast I would never want to be part of it, but, as a scientist, I have to support it. As cruel as some Axolotl research may appear, it has incredible value for degenerative diseases in children, post-surgery healing for geriatric populations and much more. Try telling the parents of a three-year-old with muscular dystrophy that they shouldn't support research which might save their child's life because it involves killing an Axolotl.

OK, that's enough editorializing for today. Obviously, I am being purposefully provocative but controversy is what got me interested in this, to begin with. For now, this thread is for discussion. I will begin the experiment in a couple months. If enough people start reading this thread I'll start compiling literature citations for the above comments and more, but barring community interest I'm going to get the ball rolling later.

 

[Tye]

You'll probably be not very popular on the forums for this, if you've read up on the other morphed axolotl threads, though you probably know this already.
Expect a high casualty rate, I haven't heard of too many surviving the morph or living long post morph.

I personally think axolotls are paedomorphic for a reason and the ability to morph is a hold over from from when the species was a normal mole salamander. Many have called it a reverse evolutionary trait as it seems to do them more harm than good, example not being able to leave the waters they were born and bred in. However something happened to create the neonatiny in them. And if was enough to cause them to thrive until habitat conditions cut their population to near zero, if it isn't already zero.

Not really sure how I feel about this. We already know they can morph. We've seen it happen. People have posted photos of the whole process. Not quite sure what else there is to gain. We know it can happen spontaneously and be induced. We know it puts stress on the animal. If the animals all survive and are well taken care of... I don't know. Seems redundant when there are already species of terrestrial salamanders to keep.
I'm not sure if morphing axolotls is the solution to wild caught tigers.

 

[tundrabadger]

Well, it seems like you can have a whole argument with yourself about this so I don't have to, which is a real time saver.

 

[RoreyRoreyRorey]

Some tiger salamanders are captive bred though. And in the US, one of the major distributors of them has a large plot of land with ponds that he breeds them in. I wouldn’t consider that captive, but it is certainly not wild. And when I talked to one of the breeders, he says that often he finds paedocannibal morphs and just paedomorphs as well, which believes me to believe that it is evolutionarily advantageous to stay aquatic. But nonetheless, I will be interested to see the results of your experiment. Do try to keep the casualty rate low if you are able. It’s always sad to see them die. And I would recommend using axolotls less than a year old, as they will not have hit sexual maturity yet. Part of what causes such a high casualty rate when morphing axolotls is that if they morph after sexual maturity, it causes a lot of problems and destabilization to their biology. At a younger age, it is easier to trip that epigenetic trait that causes most mole salamanders to become terrestrial before hitting sexual maturity. Good luck!

 

[Birby]

I do not believe there is anything to gain from this as the stated before the whole process has already been documented and there isnt a need or desire for morphed axies.

however I am curious to see how this goes.

 

[Otterwoman]

I read an account of greater sirens maintained without food at 22 degrees C. One died after 26 months and losing 45% of its body weight. A second died after 5.2 years and losing 86% of its initial body weight.

I read an account of a tortoise that survived for 30 years when accidentally trapped in a box.

The former was done in the name of 'scientific curiosity.'

If creatures are not meant to be starved and kept in substandard conditions, they would not have the ability to survive such conditions. True ????


I can think of other "experiments done in the name of science" that I don't think were really very nice, even though they may have produced valuable information.

 

[xxianxx]

Tiger sals are bred in captivity though they are harder than axolotls , atleast one of the mods and John the founder have done so, as have other members of this group. In the EU cb tigers appear to be as common, if not more so than wc. So using the proposition that tiger sals cant be captive bred to justify your experiment is wrongheaded Axolotl metamorphasis is well documented and falls into three categories. 1) "Spontaneous" , some axolotl morph for no apparent reason, anecdotal evidence says they are generally healthy 2) "hormonally induced" , wether these axolotl are healthy is debatable, some sources cite reduced life expectancy others would dispute this. 3)"forced", these axolotls are exposed to substandard conditions , they die fast. If you take the time to read past post in this group you will see this. Your experiment is to force axolotl to morph , your going to kill them so i doubt your going to get much support in this group. What do you think your going to add to scientific knowledge anyway ? Axolotl have been widely studied and i doubt that killing a few more will achieve anything other than satisfy your morbid curiosity.

 

[ShrimpShepherd]

A salamander performing a research that provides no benefit to the Axolotl through stress and forced morphing. I am adamant about live research if it provides benefit and great insight into the human race and or the lives of the animals being tested, given that the methods aren't unusually cruel.

Unfortunately, this "experiment" seems to be rather pointless as it has already been documented, doesn't provide neither benefit nor insight for humans and Axolotls.

To refute your "opinions to be investigated",
1. You say that if it was useless or naturally morph, they wouldn't have the ability to. Sure, they can "naturally" morph under poor conditions (unless you mean't naturally out of coincidence in an ideal environment). However, I see this comparable to a vestigial structure, something over time, even evolution has been unable to get rid of, yet something behavioral or physical that we have. This may be the same for Axolotls, except unlike mammals with a coccyx, axolotls have the ability to morph.

2. Even I don't understand where you say Axolotl's need iodine or other hormone inducing chemicals to make them morph; for the most part, the majority of Axolotl owners believe it derives from adverse water conditions, a sudden "shock" factor from age, overcrowding, and or poor genetics. Considering you say from the article 10% of those Axolotls of a group of hundreds morphed in a 3 hour ride, I can only imagine how much water there was available, the overcrowding, the care taken prior to loading, and the water conditions during the 3 hour "ride".

3. It is, in fact, cruel and your comparison to simply having captive Axolotls or organisms is flawed. In the wild an organism is most likely a prey somewhere down the food web, hence giving adequate space, food, and a comfortable living environment without the stress of hunting and surviving is, as some deem, to be rather saving than cruel. In that case, all aquarists would be cruel, and all the owners of avians would be committing animal cruelty?

If you are doing this for fun, it is more to show the cruelty in this. There is really no beneficial point to this in the first place - putting Axolotls under extremely adverse conditions to the point they must metamorph to simply hope they can survive the conditions, but out of fun, I guess it's difficult to explain further at this point.

"Studying" this to try to sell metamorphosed Axolotl's instead of Tiger Salamanders which are actually protected species, is ridiculous. Attempting to force these organisms to metamorphose under uncomfortable conditions in order to earn a profit, disguised as an effort to help Tiger Salamanders in the wild? No thanks, and not buyin' it. There's a reason some animals are protected and illegal in some states and countries, and having alternatives are nice, such as a Savannah in place of a Serval, but having the morph an Axolotl so you can have something that resembles a Tiger Salamander? I beg to differ.

 

[curtpw]

A salamander performing a research that provides no benefit to the Axolotl through stress and forced morphing. I am adamant about live research if it provides benefit and great insight into the human race and or the lives of the animals being tested, given that the methods aren't unusually cruel.

Unfortunately, this "experiment" seems to be rather pointless as it has already been documented, doesn't provide neither benefit nor insight for humans and Axolotls.

To refute your "opinions to be investigated",
1. You say that if it was useless or naturally morph, they wouldn't have the ability to. Sure, they can "naturally" morph under poor conditions (unless you mean't naturally out of coincidence in an ideal environment). However, I see this comparable to a vestigial structure, something over time, even evolution has been unable to get rid of, yet something behavioral or physical that we have. This may be the same for Axolotls, except unlike mammals with a coccyx, axolotls have the ability to morph.

2. Even I don't understand where you say Axolotl's need iodine or other hormone inducing chemicals to make them morph; for the most part, the majority of Axolotl owners believe it derives from adverse water conditions, a sudden "shock" factor from age, overcrowding, and or poor genetics. Considering you say from the article 10% of those Axolotls of a group of hundreds morphed in a 3 hour ride, I can only imagine how much water there was available, the overcrowding, the care taken prior to loading, and the water conditions during the 3 hour "ride".

3. It is, in fact, cruel and your comparison to simply having captive Axolotls or organisms is flawed. In the wild an organism is most likely a prey somewhere down the food web, hence giving adequate space, food, and a comfortable living environment without the stress of hunting and surviving is, as some deem, to be rather saving than cruel. In that case, all aquarists would be cruel, and all the owners of avians would be committing animal cruelty?

If you are doing this for fun, it is more to show the cruelty in this. There is really no beneficial point to this in the first place - putting Axolotls under extremely adverse conditions to the point they must metamorph to simply hope they can survive the conditions, but out of fun, I guess it's difficult to explain further at this point.

"Studying" this to try to sell metamorphosed Axolotl's instead of Tiger Salamanders which are actually protected species, is ridiculous. Attempting to force these organisms to metamorphose under uncomfortable conditions in order to earn a profit, disguised as an effort to help Tiger Salamanders in the wild? No thanks, and not buyin' it. There's a reason some animals are protected and illegal in some states and countries, and having alternatives are nice, such as a Savannah in place of a Serval, but having the morph an Axolotl so you can have something that resembles a Tiger Salamander? I beg to differ.

My purpose isn't just to document the process, it is also a matter of refining the process and making it a little more predictable. The idea is to make it easier so that lots of people can do this. Ideally inducing metamorphosis in Axolotls would be as common as keeping Tiger Salamanders.

 

[curtpw]

Some tiger salamanders are captive bred though. And in the US, one of the major distributors of them has a large plot of land with ponds that he breeds them in. I wouldn’t consider that captive, but it is certainly not wild. And when I talked to one of the breeders, he says that often he finds paedocannibal morphs and just paedomorphs as well, which believes me to believe that it is evolutionarily advantageous to stay aquatic. But nonetheless, I will be interested to see the results of your experiment. Do try to keep the casualty rate low if you are able. It’s always sad to see them die. And I would recommend using axolotls less than a year old, as they will not have hit sexual maturity yet. Part of what causes such a high casualty rate when morphing axolotls is that if they morph after sexual maturity, it causes a lot of problems and destabilization to their biology. At a younger age, it is easier to trip that epigenetic trait that causes most mole salamanders to become terrestrial before hitting sexual maturity. Good luck!

Can you provide some links or citations? I've never heard of this but I'm interested. Its not as if Tiger Salamanders have never been bred - it's just so difficult that it isn't realistic for the pet trade.

 

[curtpw]

You'll probably be not very popular on the forums for this, if you've read up on the other morphed axolotl threads, though you probably know this already.
Expect a high casualty rate, I haven't heard of too many surviving the morph or living long post morph.

I personally think axolotls are paedomorphic for a reason and the ability to morph is a hold over from from when the species was a normal mole salamander. Many have called it a reverse evolutionary trait as it seems to do them more harm than good, example not being able to leave the waters they were born and bred in. However something happened to create the neonatiny in them. And if was enough to cause them to thrive until habitat conditions cut their population to near zero, if it isn't already zero.

Not really sure how I feel about this. We already know they can morph. We've seen it happen. People have posted photos of the whole process. Not quite sure what else there is to gain. We know it can happen spontaneously and be induced. We know it puts stress on the animal. If the animals all survive and are well taken care of... I don't know. Seems redundant when there are already species of terrestrial salamanders to keep.
I'm not sure if morphing axolotls is the solution to wild caught tigers.

The idea that morphed Axolotls live shorter lives is pure myth. Several studies have been done in which sexually mature Axalatls were induced into metamorphosis byThyroxine injection - and that definitely did shorten their lifespan. I think those studies are what got this myth rolling. At this point, I've read through quite a bit of lit. If you can provide some citations though I'm interested.

RE "I personally think axolotls are paedomorphic for a reason": actually, there is a stronger argument that they can be both terrestrial and aquatic for a reason! (if by "reason" you mean evolutionary advantage). What an incredible adaptation.

 

[curtpw]

I read an account of greater sirens maintained without food at 22 degrees C. One died after 26 months and losing 45% of its body weight. A second died after 5.2 years and losing 86% of its initial body weight.

I read an account of a tortoise that survived for 30 years when accidentally trapped in a box.

The former was done in the name of 'scientific curiosity.'

If creatures are not meant to be starved and kept in substandard conditions, they would not have the ability to survive such conditions. True ????


I can think of other "experiments done in the name of science" that I don't think were really very nice, even though they may have produced valuable information.

On a general note, there is scientific evidence that periodic fasting is beneficial to most vertebrates, even humans ( https://www.cell.com/cell-metabolism/fulltext/S1550-4131(18)30130-X ).

I'm not talking about starving Axolotls. I'm talking about feeding them once every two weeks (more research to do on specific numbers) for a month or two, then giving them a break. The idea is to apply a variety of pressure so you don't put that animal under too much stress from any particular factor.

The NYTimes published an interesting article arguing that keeping any reptile or amphibian as a pet is unethical: https://www.nytimes.com/2017/11/10/science/reptiles-amphibians-pets.html

I have friends who think that keeping a wild animal of any kind locked up in a cage (a "pet") is immoral. I don't agree with them, but there is a strong argument to be made that keeping an Axolotl as a pet under any condition is unethical. Nothing I am proposing is more stressful than shipping an animal in the mail (considering the condition of some packages I get, a great deal less stressful!). If you anthropomorphize salamanders, it is very difficult to defend keeping them as pets at all. If I was a salamander, I would definitely not want to be anyone's pet.

One of the reasons I'm publishing all this on Caudata is because it is an opportunity for fresh perspectives on an interesting subject. I know I've enjoyed reading and responding to all the replies on this thread.

 

[xxianxx]

Can you provide some links or citations? I've never heard of this but I'm interested. Its not as if Tiger Salamanders have never been bred - it's just so difficult that it isn't realistic for the pet trade.

Search this site for breeding tiger sals , there are a few threads. One area of your experiment you need to review is your belief that a three hour journey caused morphing . Axolotl are routinely shipped over long distances for days , morping would be relatively common if this was a cause but its not. The most likely cause was the regular care standards slipped before shipping. Do you know what the mortality rate was after morphing ?