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Comment by cbolton | Hacker News Reader

A very interesting animal. A biology professor told me a story that went something like this: these animals were known for seemingly staying in a larval state for their whole life, an extreme case of neoteny. Scientists brought some specimens back to Europe to investigate. But when visitors came to witness the eternal larvae, they had actually started to transform into adults. It turns out a change of environment or other stress factor must have triggered the metamorphosis. These animals can "choose" to grow into adults or stay as larvae till the end.

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Sounds like your professor's story involved the cousin of the axolotl, the tiger salamander. They can live an entire life in a larval state or they can undergo metamorphosis. The axolotl cannot, their adult form is their larval one.

These two creatures are so often mistaken that most pet stores selling axolotls are actually selling tiger salamanders. https://en.m.wikipedia.org/wiki/Axolotl

The professor's story is potentially this one detailed in the very Wikipedia article you linked:

> Six adult axolotls (including a leucistic specimen) were shipped from Mexico City to the Jardin des Plantes in Paris in 1863. Unaware of their neoteny, Auguste Duméril was surprised when, instead of the axolotl, he found in the vivarium a new species, similar to the salamander. [verification needed] This discovery was the starting point of research about neoteny. It is not certain that Ambystoma velasci specimens were not included in the original shipment. [citation needed] Vilem Laufberger in Prague used thyroid hormone injections to induce an axolotl to grow into a terrestrial adult salamander. The experiment was repeated by Englishman Julian Huxley, who was unaware the experiment had already been done, using ground thyroids. [39] Since then, experiments have been done often with injections of iodine or various thyroid hormones used to induce metamorphosis. [16]

I don't recall clearly so that's certainly possible, but it seems the Axolotl does have the capability of spontaneous metamorphosis. Here are quotes from some publications I found.

First, regarding the first individuals imported in Europe [1]:

"In November 1865, Duméril issued another report to the Académie des sciences. One of the axolotls had started to become “markedly different from the other axolotls of the same age.” Soon, others followed. The external gills disappeared, and the form of their heads and bodies changed along with their coloration. Several animals that were born in the Collection had left the water and had transformed into a land-dwelling form. They had become what Duméril called “ambystomes.”"

Then this extract of a Master's thesis [2]:

"Six A. mexicanum were transferred to Paris where Dumeril (1870) subsequently reported that individuals reproduced in an aquatic, larval state and that some of the resulting offspring underwent a metamorphosis. Smith (1989) suggests that some of the original stock that arrived in Paris included closely related members of the Tiger salamander species complex, that are capable of expressing a paedomorphic or metamorphic life history. However, it seems likely that domestication altered the penetrance for expressing paedomorphosis and the original axolotl stock was pure A. mexicanum that maintained a higher propensity to express metamorphosis in nature (Voss & Shaffer, 2000). Even though metamorphic forms have been culled from the Ambystoma Genetic Stock Center axolotl collection for decades, the frequency of spontaneous metamorphosis is only 1–2%, with a 10% frequency observed if A. mexicanum experience stressful conditions (Randal Voss, unpublished data)."

And this from a book chapter [3]:

"The modern axolotl strain used in most laboratories is a highly inbred population that most likely arose from a donation of seven wild axolotls (six wild-type and one white mutant) between 1863 and 1866 to the Paris Natural History Museum [6] . In fact, most modern-day laboratory axolotls likely have a direct lineage to these founders, and all white mutants are descendants from this single white animal [7]. A few wild-caught axolotls were introduced into the colony strain in the 1960s including an albino tiger salamander (Ambystoma tigrinum) [8], but overall the present-day laboratory strain is likely one of the most long-running inbred strains of any laboratory species. The 150-year history of laboratory breeding seems to have selected against spontaneous metamorphosis (currently <1 % frequency), as it is more prevalent in wild strains than the lab strain [7, 9]. The most extensive colony of laboratory axolotls is maintained at the Ambystoma Genetic Stock Center (AGSC)"

In particular this part: "The 150-year history of laboratory breeding seems to have selected against spontaneous metamorphosis (currently <1 % frequency), as it is more prevalent in wild strains than the lab strain."

[1] https://www.brepolsonline.net/doi/full/10.1484/J.CNT.5.13210...

[2] https://uknowledge.uky.edu/biology_etds/13/

[3] https://link.springer.com/protocol/10.1007/978-1-4939-2495-0...

there's also an instagram user who specializes in rescuing morphed axolotls: https://www.instagram.com/salamanderwithasign

i think some of the recent posts are about a batch of salamander/axolotl hybrids, but if you scroll further down, there's more of the morphed axolotls they have.

According to my family, I'm a 35 year old man-child so apparently humans can do the same. I don't want to find an out if a strong enough stressor turns me into and adult or not.

Try marrying. Nothing stresses you into a man like trying to forge a life with someone else.

Try having kids, building a life with someone is easy mode until you throw multiple children into the mix. It's the final milestone of the human metamorphosis and it's a challenge.

Been there, done that. Bought one of the kids an axolotl after lots of pester-power and boatloads of "I promise I'll look after it, feed it and clean its tank every day".

So it's come to pass that now I look after it, and every time there's a new "Dad, can I have a XXX as a pet?" I can say "Well, you haven't looked after the axolotl". And since they can live for 25 years, there is some method to my madness ;)

Don't agree to care for their parrot, it ought to outlive you both.

That's why RMS has a "I'd love to meet your parrot, but please don't buy me one" rider in his speaking contract.

Or a turtle / tortoise!

Contrary to what others have replied there are much more stressful situations than being a father/husband and they're such that you may never want to be one!

> I don't want to find an out if a strong enough stressor turns me into and adult or not.

Stress doesn't necessarily mean you have to grow up in the sense that you stop having fun. It just means you notice subtleties, know better, and are otherwise prepared for whatever life throws your way. In many ways this just makes life more fun.

> These animals can "choose" to grow into adults or stay as larvae till the end.

Just like professional DJs and rock-stars

What do you do for a living so we can shit on it

An ex-pro DJ :D

https://ra.co/dj/paullouth

How did you go from DJing Fabric to a healthcare company? Haha, just genuinely curious

That's not quite the path, but it sounds good haha!

When I was in my early teens, just discovering electronic music for the first time (mid 80s) - but also teaching myself to program on a BBC Micro - I had two dream jobs for "when I grow up":

1. Write computer games

2. Be a rock star

When I was 21 I moved to London to be the sole programmer on the PS1 sku of a game [1] for Eidos (didn't have any experience in that either). Then proceeded to work for 10 years in the games industry, before starting the healthcare company.

During my 20s I also started running parties in London, which then turned into a major residency, and playing all over the world. But, mostly I focused my efforts on playing in London; the traveling part of DJing - although pretty rockstar-esque - is actually usually a few hours of fun surrounded by an epic amount of traveling/sitting in airports. So, because I already lived in probably the centre of the world when it came to music, I kept my focus there.

I was earning enough from DJing to quit the Mon-Fri job, but what happened with games, during the period where I started getting success as a DJ, was that (although a good job) it became 'just-a-job'.

So one of my dreams was slowly dying. I never wanted that to happen with music, so I never went ‘all in’, even though I could have done it because I was earning enough from it. It's a decision I'm glad I made, because music has always been fun, and I've never had to compromise or sell-out. And the rent has always been paid.

So many of the people I came up with at the time, who are now on the downside of their career (not considered cool any more) are not in good places. Which is pretty hard to see.

It happens to us all. Fabric is obviously the thing you pick up on, because it's one of the major world clubs: I played there every year for 6 years running (in the good years too, 2006-2012) and then nothing ever again. It can really knock you if you have nothing else to fall back on.

The healthcare thing came about because I was ready to jump ship from games. And coincidentally I was recommended as a good programmer (by my old boss) to the people I am now partners with. Just a case of right time, right place, and right mental place for me ... I was ready to do something a bit more impactful.

I knew nothing about healthcare either :D

[1] https://www.unseen64.net/2020/11/16/lunatik-pure-entertainme...

This is a really good response, thanks for taking the time to write it all out. I once was going to use software engineering to pay the bills so I could DJ at night. Then life changed and I got carried away being happy with other obsessions.

Happy Wednesday :)

forum-poster, so similar.

disagree

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