Euthanasia by ethyl alcohol

[eljorgo]

I think we have to distinguish between freezing temps in the environment and the actual temperature in the animals' tissues. What Az is saying is that most likely most caudates can not let their tissue temperatures go much below freezing. A caudate active on or below snow may have a body temperature a few degrees above freezing.

After all, the main reason that amphibian and reptile species are so few in areas of permafrost is that they can NOT find frost-free refugia there during winter. Only a few species, like the wood frog, have adaptations to survive freezing

Now here goes a very charismatic discussion on physics. So to you all calming that Caudate's in the wild are a few degrees warmer than the negative or 0ºC surroundings can you tell me how this wonder on physics its possible? Going on this brainstorm tomorrow there is people calming the gravity is a lie and the earth is square...

People, please this is Zeroth law of thermodynamics.... A salamander body is comparable to a stone since it doens't produce or has internal energy in the form of heat. As so according to one of the most basic laws in the world of physics this same body is in thermal balance with its surrounding environment. If the salamander is resting under ice (this same being -5ºC the salamander's body is facing -5ºC! Period.). Imagine you're at a cool, snow covered landscape. The thermometer marks -6ºC. Will a stone have 4ºC? A tree branch -2º? leaf litter 0ºC? This is Impossible physics people...

 

[ozarkhellbender]

As their blood and tissues are only a few degrees warmer than their surrounds, crystallisation occurs whilst the animal is still able to feel it.

I think we have to distinguish between freezing temps in the environment and the actual temperature in the animals' tissues. What Az is saying is that most likely most caudates can not let their tissue temperatures go much below freezing. A caudate active on or below snow may have a body temperature a few degrees above freezing.

And that is indeed my point, Molch. Even if air temperature is very low and surface temperature too, you won´t find those species at a microclimate that is below 0ºC (or perhaps some species slightly less than that) or meassure body temperatures any lower. They appear to be at freezing temperatures, but they aren´t.
I can attest from the experience of others that Ichthyosaura alpestris does not tolerate freezing. They happily tolerate 2ºC but they won´t survive if their tissues go below 0.
For example, close to home, the spanish subspecies Salamandra salamandra almanzoris inhabits an area that is completely covered with snow for many months. They, however, shelter below ground where the soil doesn´t freeze and wait. Right during the spring melt , when temperature goes reliably above 0ºC during the day or night, they emerge to lay their larvae. You can even see them on the snow as if sunbathing. Their bodies are never exposed to below 0ºC. The same habitat is used by Bufo bufo, Rana iberica y Pelophylax perezi and neither of those can tolerate freezing either.

It´s also the same reason why you can see terrestrial caudates about during cold periods, but not during freezing periods. They are safe in a freeze-free microenvironment.

Surviving being frozen is a trick that few species can manage

Ok, I am confused. I am not sure how an animal incapable of generating it's own body heat could have a body temperature above freezing, and yet be living beneath snow, which we all know is water at or below freezing. Am I missing something? If we were discussing a mammal, ok, sure, valid point. We are discussing poikilothermic, ectothermic animals here.

 

[Azhael]

So salamanders produce absolutely no heat at all?
I´m pretty sure anything with a respectable body mass and a methabolism produces at least some heat. It´s not just endotherms that burn calories. Even if it were just the heart pumping or other muscles contracting they will produce some heat.
Anyway, that is beside the point. The point remains that most salamander species are simply not exposed to temperatures below 0ºC. If you meassure their body temperature, it is above freezing. It doesn´t matter what the air temperature is, what matters is wether the frost line reaches where the salamander is and the surrounding groundwater freezes or not. If it doesn´t freeze then you are above 0ºC, however marginally that may be. I´m positive Molch Stark could speak volumes about frostlines and permafrost
It´s an easy but lethal and wasteful experiment to conduct to see if most species tolerate freezing or not.

 

[ozarkhellbender]

So salamanders produce absolutely no heat at all?
I´m pretty sure anything with a respectable body mass and a methabolism produces at least some heat. It´s not just endotherms that burn calories. Even if it were just the heart pumping or other muscles contracting they will produce some heat.
Anyway, that is beside the point. The point remains that most salamander species are simply not exposed to temperatures below 0ºC. If you meassure their body temperature, it is above freezing. It doesn´t matter what the air temperature is, what matters is wether the frost line reaches where the salamander is and the surrounding groundwater freezes or not. If it doesn´t freeze then you are above 0ºC, however marginally that may be. I´m positive Molch Stark could speak volumes about frostlines and permafrost
It´s an easy but lethal and wasteful experiment to conduct to see if most species tolerate freezing or not.

So you are saying that caudates produce enough body heat to compensate for freezing temperatures? So caudates can survive in environments at freezing temperatures? But didn't you just say they couldn't survive at freezing temperatures? If the caudate is covered in snow, doesn't that mean the frostline has reached the caudate? I know a thing or two about freezing temperatures and frostlines too. It reaches below freezing temperature here every year. It also snows here every year. In fact, earlier this year, it reached -29C.

 

[eljorgo]

So salamanders produce absolutely no heat at all?
I´m pretty sure anything with a respectable body mass and a methabolism produces at least some heat. It´s not just endotherms that burn calories. Even if it were just the heart pumping or other muscles contracting they will produce some heat.
Anyway, that is beside the point. The point remains that most salamander species are simply not exposed to temperatures below 0ºC. If you meassure their body temperature, it is above freezing. It doesn´t matter what the air temperature is, what matters is wether the frost line reaches where the salamander is and the surrounding groundwater freezes or not. I´m positive Molch Stark could speak volumes about frostlines and permafrost
It´s an easy but lethal and wasteful experiment to conduct to see if most species tolerate freezing or not.

I'm preaty much done with this. This is Zeroth law of thermodynamic. This part as any other part of physics is rolled by unchangeable facts. Off course one can invent fake facts and try to make others believe them but that's not polite to my eye.
Anyway I´m positive ozarkhellbender could speak volumes about frostlines and permafrost with salamanders living right bellow them.

 

[Molch]

any kind of metabolism produces heat. Cells use glucose to produce ATP, and heat is one of the byproducts (first law of thermodynamics, btw). So yes, a salamander produces a small amount of heat. If it's only 1 or even 1/2 degrees above ambient temperature, that makes the difference between life or death at the freezing point.

Also, any object, even an inanimate blob of goo, will absorb some radiation from the sun (yes, even on cloudy days) and heat up minimally in relation to the ambient environment. So yes, a salamander crawling around the snow, by these two simple mechanisms, can be just one or two degrees warmer than the environment.

The best way to test this is to take a very sensitive thermometer out there and measure microclimate in pockets beneath the snow, under a root, just an inch down the soil etc. You'd be surprised how much variation there is, and how much warmer some of these microhabitats are compared to air temperature.

better even, if you had a small probe you could stick up a sal's butt to measure its temperature. I'm sure it's been done somewhere by someone. Maybe I'll find a reference

 

[Azhael]

No, Ozark, i did not say that. I said they produce some heat, i ignore how much methabolic heat they produce, but it´s definitely some.

Eljorgo please point out which bits of what i said are fake. To the best of my knowledge and every single professor i´ve had, metabolisms produce heat. Even bacteria do...
And if that´s not the point you object to, then show me how all salamanders can tolerate freezing.

 

[Molch]

So you are saying that caudates produce enough body heat to compensate for freezing temperatures? So caudates can survive in environments at freezing temperatures? But didn't you just say they couldn't survive at freezing temperatures? If the caudate is covered in snow, doesn't that mean the frostline has reached the caudate? I know a thing or two about freezing temperatures and frostlines too. It reaches below freezing temperature here every year. It also snows here every year. In fact, earlier this year, it reached -29C.

but you don't have permafrost in MO Even at 29 below air temp, the unfrozen soil under a root or such is still, well, unfrozen.

The ultimate test (which of course you won't do) is to stick a sal in the freezer and see if he survives it. Do you really expect it to?

 

[ozarkhellbender]

but you don't have permafrost in MO Even at 29 below air temp, the unfrozen soil under a root or such is still, well, unfrozen.

The ultimate test (which of course you won't do) is to stick a sal in the freezer and see if he survives it. Do you really expect it to?

I know I don't have permafrost in MO. What is the definition of permafrost? Is it not soil which REMAINS frozen for TWO OR MORE years? The soil here does indeed freeze. It just does not stay frozen all year long.

Yes, I really do expect it to survive. I would have no problem with testing it, what species would you like me to test?

 

[Molch]

I know I don't have permafrost in MO. What is the definition of permafrost? Is it not soil which REMAINS frozen for TWO OR MORE years? The soil here does indeed freeze. It just does not stay frozen all year long.

Yes, I really do expect it to survive. I would have no problem with testing it, what species would you like me to test?

permafrost is when soil stays permanently frozen after a certain depth. Then in the summer only the upper soil layer (maybe several feet) become thawed. This limits amphibian distribution because they cannot escape winter frosts by going deeper into the soil, because they will be trapped between the ice beneath and the new frost forming in the upper layers. Areas with permafrost have ONLY those amphibian species who have specially adapted to withstand freezing.

As for testing your theory with a sal in the freezer, for heaven's sake, Please Don't!! You'll kill the poor thing. I mean, seriously. :rofl:

 

[Molch]

A lot of research has been done on wood frogs, the only amphibian to go beyond the Arctic circle in North America (think about it: if sals were as freeze tolerant as you think, why wouldn't more species live in the far north? We sure have enough wetlands here).

Woodfrogs have unique adaptations to survive freezing. They flood their cells with glucose, which prevents water loss from cells when the spaces between the cells form ice crystals. In freezing injuries, it is this osmotic water loss that causes the most damage to tissues: as water outside cells freezes, its osmotic pressure rises and water is drawn from cells, and the cells die. Wood frogs prevent this by putting so much glucose into their cells that the osmotic pressure of the cells remains sufficient to keep the water.

I imagine some species like keyserlingii has similar adaptations, but most other amphibians don't

also, animal tissues don't freeze at exactly 0 degrees. They have much higher solute concentrations than plain water and therefore freeze at slightly lower temps, maybe -0.5 or -1 degree C.

I think it's entirely possible that there are other freeze-tolerant species that haven't been studied yet, but it's by no means all salamanders

 

[ozarkhellbender]

permafrost is when soil stays permanently frozen after a certain depth. Then in the summer only the upper soil layer (maybe several feet) become thawed. This limits amphibian distribution because they cannot escape winter frosts by going deeper into the soil, because they will be trapped between the ice beneath and the new frost forming in the upper layers. Areas with permafrost have ONLY those amphibian species who have specially adapted to withstand freezing.

As for testing your theory with a sal in the freezer, for heaven's sake, Please Don't!! You'll kill the poor thing. I mean, seriously. :rofl:

Ok, so, given that the soil here does freeze in winter, and that snow is itself freezing, then any caudate between the frozen soil and the snow would not be able to escape the freezing temperatures. Is this correct? So the caudates here found below the snow in winter are surviving freezing temperatures.

You THINK that will kill the salamander. However, I have no problem with testing it because I believe the caudate in question would survive. Actually, there is someone on this forum who froze his Laotriton laoensis without any harm coming to said caudates.

 

[ozarkhellbender]

A lot of research has been done on wood frogs, the only amphibian to go beyond the Arctic circle in North America (think about it: if sals were as freeze tolerant as you think, why wouldn't more species live in the far north? We sure have enough wetlands here).

Woodfrogs have unique adaptations to survive freezing. They flood their cells with glucose, which prevents water loss from cells when the spaces between the cells form ice crystals. In freezing injuries, it is this osmotic water loss that causes the most damage to tissues: as water outside cells freezes, its osmotic pressure rises and water is drawn from cells, and the cells die. Wood frogs prevent this by putting so much glucose into their cells that the osmotic pressure of the cells remains sufficient to keep the water.

I imagine some species like keyserlingii has similar adaptations, but most other amphibians don't

also, animal tissues don't freeze at exactly 0 degrees. They have much higher solute concentrations than plain water and therefore freeze at slightly lower temps, maybe -0.5 or -1 degree C.

It is true that Wood Frogs are the only amphibians to go beyond the Arctic circle. Why other species haven't, I have no idea.

Here is something you might find interesting:
Turtles survive being frozen - YouTube

 

[Molch]

You THINK that will kill the salamander. However, I have no problem with testing it because I believe the caudate in question would survive. Actually, there is someone on this forum who froze his Laotriton laoensis without any harm coming to said caudates.

the temperature in a household freezer is far too cold for any sal to survive. Even a freeze-tolerant species like a wood frog wouldn't survive that much freezing. Please, don't do it!

 

[Molch]

Ok, so, given that the soil here does freeze in winter, and that snow is itself freezing, then any caudate between the frozen soil and the snow would not be able to escape the freezing temperatures. Is this correct? So the caudates here found below the snow in winter are surviving freezing temperatures.

but....the very fact that the sal was active below the snow proves that it was NOT frozen. Freezing means the formation of ice crystals in the tissues. If that had been the case, it would have been a rigid little popcicle and unable to move. The fact that it was active shows that its tissues were either still above freezing, or that there was enough glucose in its cells to lower the freezing point to a few degrees below 0 C.

In any case, it's a matter of only a few degrees. Even the hardy wood frog wouldn't tolerate having its temp lowered to 15 or 18 below C, as lab experiments have shown (if you google cryobiology and wood frog, you get some references). At those temps, simply too much ice forms in the tissues for the frog to recover.

 

[ozarkhellbender]

but....the very fact that the sal was active below the snow proves that it was NOT frozen. Freezing means the formation of ice crystals in the tissues. If that had been the case, it would have been a rigid little popcicle and unable to move. The fact that it was active shows that its tissues were either still above freezing, or that there was enough glucose in its cells to lower the freezing point to a few degrees below 0 C..

Wait a minute, who said anything about them being active? I just said they were under the snow, I said nothing about them being active.

 

[JacksonR]

I don't think caudates produce much heat...but this thread is starting to. :lol:

 

[eljorgo]

Wait a minute, who said anything about them being active? I just said they were under the snow, I said nothing about them being active.

Wait two minutes... Who said they would be frozen? They are neither frozen or neither active. They just are... I know I never saw them but I've heard also from a few other US folks from PA and VA (Who do cool their salamanders even under -5ºC Temps) That state similar reports of Eurycea and Pseudotriton just under the under 0ºC Ice. They do not move and they are not frozen.

I don't think caudates produce much heat...but this thread is starting to. :lol:

Thing is the amount of heat they produce on the overall matches nearly into zero. Witch transales to, no heat. I doubt in the best change due to their mass and the specific heat capacity of most organic compounds and mostly of body water % will not let them heat more than in the order of centesimals Celsius. The thread is starting because the specific point is never touched from both sides of subject at same time. Thats why the path of the thread is an S instead of a simple I

Cheers,

 

[Molch]

also, keep in mind that freeze tolerance is not an absolute. It's a matter fo degrees. A species may be freeze tolerant to just a degree or two below zero C, and another species may tolerate freezing to lower temps, such as the wood frog, which is why it can live where others cannot. The point being, a sal or frog needs to remain unfrozen in order to be active (active in the metabolic sense: heart beating, blood flowing; it doesn't necessarily mean walking around or doing handstands). If frozen, it would be completely rigid. If you moved it, it might break like an icicle (yes, mean people do that to wood frogcicles up here).

in any case, I doubt any species will tolerate freezing to 18 or 20 below, which is the temp of a typical household freezer. The size and speed of ice crystal formation would simply be too much

 

[Molch]

I don't think caudates produce much heat...but this thread is starting to. :lol:

:lol: nah - just having a lively scientific debate, which is totally cool...it doesn't get really heated until we get out the turkey basters and start shooting newt poop bombs at one another.

I think we haven't really standardized our definitions: Some of us talk about freezing animals, others talk about cooling them below 0 degrees C, which is not the same as freezing.

here my summary so far:

Quite a few species can remain active (meaning, heartbeat and blood flow) below 0 degrees if they have enough natural antifreeze in their tissues (eg glucose). Everybody seems to agree with this.

Freezing means formation of ice crystals between the cells in the tissues. The animal turns into a rigid little popcicle, and heartbeat and blood flow cease entirely. The colder the temp, the more extensive the crystal formation. Too much, and the cells get damaged beyond repair, so there is a limit of tolerable temperatures for each species. Azhael and I maintain that NOT all caudates are adapted to survive actual freezing. Species known to be able to are keyserlingii, the wood frog, and probably some others who haven't been studied yet. But not all of them, and possibly only a small minority.