Triturus Marmoratus embryonic development

[Molch]

If I am successful with this bunch, I will be more than happy to pay it forward if you could reimburse with shipping. There is no way it would be fair to keep all these babies to myself and Dawn was sweet enough to share with me.

ahh, that's sweet....but it turns out that Dawn, the Queen of Newtdom, :angel: has taken pity on my poor marm-less heart and sent me another batch of eggs.

These ones look to be developing fine. They are very fresh yet, and are only in the tail-bud stage, but under the magnifying lens I can definitely see that the embryos are shaping up.

I got about 80 eggs, so I reckon about half will fall victim to that genetic thing, which should leave a good crop of larvae. I have them at 58 F, so it'll be at least another 2 weeks before they hatch.

I hope to raise enough to start my own lil' Marmoratus colony, and if I have more, I can give some away in a year or so

 

[esnailme]

I am happy that Dawn took care of you. Wishing you well with your future babies.

 

[Otterwoman]

OK but just so you know, the real queen of Newt-dom is Jennewt.

 

[esnailme]

Well if she is half as kind and generous as you.....

May caudata.org crown you both Queen of newt-dom :famous:

 

[Molch]

(well, in a progressive kingdom there can be 2 queens...)

ya know, I've never actually laid eyes on a real-life marmoratus before. Only in pictures. When these hatch, they'll be the first-ever marms I behold with my very own uncovered rheumy old eyes.

When I was 13, my Dad borrowed a camper van and took my brother and me on a trip through France. The idea was that we were going to be cultured little Europeans and visit all the museums and the cathedrals and admire every last pile of rubble left behind by the Romans.

Little did my dad know that the real purpose of the trip turned out to be to stop at every ditch, creek, puddle, pond or meadow so that my brother and I could go butterflying (him) and newting (me). My great ambition was to find a marmoratus. Of course, I found just about any other herp native to France except the marmoratus. Never saw a single one. I pleaded with my Dad to extend the trip all the way through the Pyrenees and into Spain, but alas, to no avail Had to go home un-marmed and disappointed....

 

[Jennewt]

OK but just so you know, the real queen of Newt-dom is Jennewt.

You get the title this spring, Dawn, with all these marm eggs you're producing. And in this oh-so-progressive kingdom, there is plenty of room for multiple queens. It still won't improve your salary.

Great story, Molch.

 

[Otterwoman]

You get the title this spring, Dawn, with all these marm eggs you're producing.

Sheesh, Jen, it's not like I'm layin' 'em myself!

Great story, Molch.

I agree!

 

[Molch]

so to ask about the genetic thing: what exactly causes it? The 50% rate would suggest some type of Mendellian thing: is it a bad gene and only heterozygous ones survive? That would explain the 50%

I went through the eggs and I have 15 good ones for sure that are now in the comma stage. The others may be duds and getting fungussy. Still, 15 is something. I have them in clean water with daily changes and a bit of aeration at 60F.

 

[Otterwoman]

Are you changing their water completely? I don't' really see that anything negative would be building up. I raise my eggs in water and don't do any changes until they start to get rather large.

 

[Azhael]

The genetic thing is one of those misteries...
I for one think that it definitely must have a purpose. Nothing like that would appear naturally and be spread over such a succesfull genus as Triturus if there wasn´t some point to it. The problem is that finding a purpose for it is no easy task. I can´t even begin to fathom what on earth can be the benefit of loosing 50% of your offspring even before hatching.
But the fact remains, all Triturus have the same condition and they are obviously very succesful when conditions permit....so it´s not as bad as it may seem from our point of view.

It´s exactly like that, Molch. Only heterozygous animals survive, and all homozygous one die before hatching, generally at the point where the tail bud is forming. The strange thing is that ALL living Triturus are heterozygous for this lethal gene. It is indeed strange, but as i said i believe there must a reason, and a good one too.

 

[Molch]

The genetic thing is one of those misteries...
I for one think that it definitely must have a purpose. Nothing like that would appear naturally and be spread over such a succesfull genus as Triturus if there wasn´t some point to it. The problem is that finding a purpose for it is no easy task. I can´t even begin to fathom what on earth can be the benefit of loosing 50% of your offspring even before hatching.
.

okay, I read up some more and it turns out that the bad gene is in fact not a gene but an entire chromosome. A genetic "destiny" like that may be pretty inescapable and cannot be easily "mutated away" by natural selection, sincs mutations happen at best one gene at a time. In order to explain the persistence of this genetic booboo through the generations, there does not need to be a benefit to it as long as it also does not provide a fitness disadvantage. It may just be that the Triturus genus evolved a way to compensate for the deficit by laying larger numbers of eggs. They are notorious for laying hundreds of eggs, aren't they?:talker:


(btw, Azhael, why does your Avatar say "sadly I live in Salamanca" What's sad about Salamanca? I'd imagine it to be a nice place...)

 

[Azhael]

They do have large clutches, but i don´t think they are significantly larger than what you can see in other Salamandridae. I imagine that perhaps at some point in their evolution, heterozygotic animals showed an advantage and so the pressence of the genetic condition was favoured and eventually fixed by simple means of natural selection (with the unusual and confussing side effect of lethal homozygotism). As you say, you don´t need any benefitial effect to justify the existence of the condition, but i do think you need it to explain how it became fixed and generalized because it certainly cannot have happened from an isolated case otherwise (it would have been selected out) and it obviously didn´t appear in the individuals of the ancestral species all at the same time. Just a thought, though...

I say sadly, because i admit i don´t like it here xD It´s nice...i guess, but it´s not for me. I don´t like the weather (too hot and dry in summer, though i like the cold winters), i don´t like the city itself, i don´t really like the "universitary" atmosphere...(i´m an 80 year old in the body of a 26 year old). There are other places in spain i´d much rather live in like the glorious, beautiful, lush north (in fact i´m going to Cantabria tomorrow and i´m already happy just thinking about it). Mind you, Salamanca has some trully unique and beautiful areas with a bonanza of herps (endemisms included), but with no car, those places may as well be in a different solar system.

 

[Otterwoman]

What are you doing that you can't move?

 

[Azhael]

Technically i´m studying biology xD
I could move to another city that has a biology university but it´s really not practical (what with all the tanks and all...). I´m stuck here until i finish my degree or i´m sent back home in shame, whatever comes first :blush:

 

[esnailme]

Quick update on the larvae:

The larvae were moved to a 5 gallon tank.

The tank is bare bottom with a fluorescent light.

A cycled media cartridge is running with an airline.

The larvae received their first generous feeding of brine shrimp.

I can see some of the larvae have begun eating the brine shrimp by the color of their tummies.

Total count of larvae = 25

 

[Molch]

awesome. Mine will start hatching in maybe a week or more.

A question: when you have them in a 5-ga, how do you clean up after brine shrimp feedings? Do you change the water completely or just siphon off dead shrimp from the bottom?

 

[esnailme]

Now that my larvae are in the 5 gallon tank, I have taken a preventative measure and attached the cycled media. I can remove the uneaten brine in 1 of 2 ways.

I can either:

1) Siphon the bottom with a baster .......which is too time consuming for me because I have 3-4 more tanks to tend to OR

I can:

2) Siphon the bottom off with an open air line, which will have a continuous pull on the uneaten food and will take less time.


As far as the amount of water that is removed......This will be just enough to the eaten food which should be about 25%. I am also trying to establish a beneficial bacteria so I will take it easy on the water change.

note: I am using water changes from my 22 gallon ghost shrimp feeder tank.

 

[Molch]

by "cycled media", do you mean some kind of box filter ?

 

[esnailme]

By cycled media I mean..charcoal and filter floss encased in a plastic cartridge or a plastic frame that has the filter floss material on the outside and charcoal is on the inside.

The media has been used on a established tank.

Some people throw their cycled media away....

I keep mine so that I can setup tanks without waiting to grow beneficial bacteria.

 

[esnailme]

I forgot to ask......how many adult t marms can be stocked to e.g. 10 gallon tank???