Wood frogs only live 3-5 years, so they probably only go through a max of 5 of these cycles. I wonder how much cellular damage they accumulate during these cycles that they can tolerate due to short lifespans. They also have ~10,000x less neurons than a mammal.
Even if you had the biochemistry that was able to do this, how many cycles could a higher life form tolerate this, assuming it would even work? Complex life seems to sacrifice some resiliency, such as the ability to regrow limbs. Amphibians already seem to be particularly adept at regeneration.
"frogs don’t freeze once and stay frozen. Instead, they spend a week or two freezing at night and thawing during the day until the temperatures drop permanently below freezing"
Curious to how long the frozen structure can "survive". I wonder if it's a good idea to freeze one such frog and thaw it centuries later (an amphibian time-traveler!)
If kept in pristine conditions (perfectly sealed to prevent evaporation leading to dehydration, deep freeze), is there a particular chemical needed for life that we might expect to break down first?
Since chemical reactions happen in the freezer just slower...
Aquatic turtles have another brumination (hibernation) strategy. Since they breathe air, yet may get trapped under the ice for months at at time, they lower their metabolism plus have adaptations such as scavenging some oxygen from the water via rectal tissues as well as other chemical activity involving glucose and calcium.
I have one at home in constant warm water, yet she can see the sky and decides to bruminate on her own: every year around this time, she starts napping in her under water hide for days or weeks at a time.
The verb ought to be brumate. But I guess the desire to pull it into line with hibernation is strong, this happens with lots of words. (Or was the influence from "rumination"?)
Now I'm wondering all kinds of things about their brain. Are they capable of forming memories, and would they retain those memories after a freeze/thaw cycle?
Effectively they're dead when they freeze. I'm assuming there's no brain activity.. Which means when they thaw they're being restored to life. I wonder if any other animals experience this
I would assume that just as a computer’s storage remains intact after a restart, these frogs’ brains have internal structure, synaptic connections etc that are preserved after a freeze/thaw cycle.
Reading about them, it seems they migrate in winter (like half a mile uphill), but the adults always return to the same breeding pond in spring, so that information is stored somewhere.
I'm not surprised. There have been studies that show caterpillars retain memories through metamorphosis into a butterfly (a process that basically liquefies them).
cant even call that hibernation. There are other knock on advantages to bieng frozen solid, it would slow down and even kill a lot of infectious microbes.It may convey a certain life extension benifit.
And threre is not much behavioral adaptation needed,frog gets chilly, snuggles under a leaf,freezes solid, gets defrosted 8 months later and wakes up hungry and horny, not bad.
> it would slow down and even kill a lot of infectious microbes
I wouldn't count on it killing them. The cryoprotectants in the frog's body don't discriminate; they'll protect foreign bacteria just as well as the frog's cells.
I should of elaborated, many of the issues associated with,"conventional hibernation"
have to do with lethal infections aquired
externaly while hibernating, damp, cold, ....mold
as to the cryoprotectants ,side protecting microbes, clearly gut microbes and other internal flora ,would benifit......but ,big but, would a sneeky cryosuspension routine also include a freeze and clense
cycle?, why not!
and easy enough to verify,right!
> ...the wood frog’s liver produces large amounts of glucose that flushes into every cell in its body. This syrupy sugar solution prevents the cells from freezing...
All natural, no preservatives added, sweetened frog popsicles! Yummy!
I'm not even joking about this -- since frog legs are a thing people eat (taste kinda like chicken), I'm now incredibly curious what this would taste like if you "caught" these in their frozen state and cooked them.
Are we taking syrupy sweet meat? Or just a hint of it?
Evolutionarily, amphibians are somewhat simpler than mammals, they're smaller than a lot of mammals and they don't live as long, so I suspect some of this is simply that "things that aren't there". They wouldn't have as many problems with advanced glycation end products because the temperature is so low. There's at least one other ice survival strategy: antifreeze proteins. The fir tree and a variety of arctic fish have these: https://pmc.ncbi.nlm.nih.gov/articles/PMC6691018/.
In all cases, I still don't understand how the membrane potentials are maintained or re-constructed in the thawing phase: any pointers?
I think there are threads in Michael Levin's work that suggest membrane voltage potential may be able to be 'encoded' to microtubule structures and converted back into voltage potentials later. I don't think it's firmly established or understood yet but seems like a promising area for research!
Perhaps because ice forms outside cells, freezing ions in place. Even if there was a very small area around ion channels that was liquid that equalized all ion concentrations with the cell, when the extra cellular fluid thaws the original concentrations would be pretty much restored
Oh god. This made me wonder, what is wood, anyway? And I've just come away much more confused.
Bamboo is a grass and doesn't come from a tree. Palm wood comes from palm trees, except palm tree trunks are apparently a totally different type of structure than other tree trunks, sounds closer to Papyrus. No growth rings, a fiber type structure. Is Papyrus wood?
Any plant matter above a certain density? I don't think that's it. Corn stalks aren't wood.
Man, I don't know. I am certain that it must be plant matter though, so yes, a wooden frog would be a biological miracle.
What's really going to bake your noodle later is that Corn is a grass, just like Bamboo.
My total armchair answer: It helps to think about trees as just giant shrubs.
Shrubs are considered "woody", but most definitely are not trees. There are plenty of trees which are close relatives of shrubs (like poison oak and the urushi tree).
So what's the difference between a grass and a tree? Walking the tree of life up from Poison Oak and Bamboo, we see we land at Monocotyledon and Eudicots. There's lots of non-woody and tough fibrous (i.e. woody) plans in both clades (palm trees are monocots, btw).
Wikipedia says if it is tough and fibrous and has growth rings it's wood:
So Bamboo, although coming from a grass and not a tree, is wood. Further reading down that page talks about density as a key quality of wood, and goes on to not definitively quality bamboo as wood or as non-wood but some are dense enough.
Ultimately, there's no super clean definition of wood is my take-away, between the technical and colloquial aspects. You can use bamboo in construction much like wood, if you cut off a bit of shrub and dry it out, it's a "stick" just as much as if you trimmed it off a tree. You can make paper out of all kinds of fibers.
It's worse than that. _Tree_ isn't even a well-defined thing.
> Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight.[1]
Wood is secondary xylem produced by growth from the vascular Cambium. (Sometimes? I think the issue is that there’s more than one definition of wood depending on context …?). Growth rings?
But palm trees aren’t truly trees, right ? Just called trees…. They’re more of a tree like shrub? I think.
Trying to learn about this through claude was kinda funny.
Ask it to tell me about wood that doesn't come from trees, and it tells me about palm wood. I say, but doesn't that come from palm trees? It says palm trees aren't technically trees because their trunk isn't wooden.
Anyway, with your definition palm wood wouldn't be wood, and neither would bamboo. Feels like the vegetable/fruit thing though, there just isn't a perfect answer.
But the article explains perfectly how they look like. White eyes, glucose filled cells, frozen solid as a rock. Bang it against a table, it's definitely frozen. Throw it back underneath those leaves.
Wood frogs only live 3-5 years, so they probably only go through a max of 5 of these cycles. I wonder how much cellular damage they accumulate during these cycles that they can tolerate due to short lifespans. They also have ~10,000x less neurons than a mammal.
Even if you had the biochemistry that was able to do this, how many cycles could a higher life form tolerate this, assuming it would even work? Complex life seems to sacrifice some resiliency, such as the ability to regrow limbs. Amphibians already seem to be particularly adept at regeneration.
"frogs don’t freeze once and stay frozen. Instead, they spend a week or two freezing at night and thawing during the day until the temperatures drop permanently below freezing"
https://shakerlakes.org/frozen-frogs/
like maple syrup...
Curious to how long the frozen structure can "survive". I wonder if it's a good idea to freeze one such frog and thaw it centuries later (an amphibian time-traveler!)
- Artificial experiment [1]: no longer than 3 months (but see disclaimer)
- New study [2]: 7 months (with 100% survival rate)
So further study seems to be needed.
[1] https://journals.biologists.com/jeb/article/216/18/3461/1160...
[2] https://journals.biologists.com/jeb/article/217/12/2193/1211...
If kept in pristine conditions (perfectly sealed to prevent evaporation leading to dehydration, deep freeze), is there a particular chemical needed for life that we might expect to break down first?
Since chemical reactions happen in the freezer just slower...
Aquatic turtles have another brumination (hibernation) strategy. Since they breathe air, yet may get trapped under the ice for months at at time, they lower their metabolism plus have adaptations such as scavenging some oxygen from the water via rectal tissues as well as other chemical activity involving glucose and calcium.
https://www.pbs.org/newshour/science/the-secret-to-turtle-hi...
https://wildlifeinwinter.com/painted-turtle
I have one at home in constant warm water, yet she can see the sky and decides to bruminate on her own: every year around this time, she starts napping in her under water hide for days or weeks at a time.
That's a word I don't know (and neither do you): brumation, invented in 1965.
https://en.wiktionary.org/wiki/brumation
The verb ought to be brumate. But I guess the desire to pull it into line with hibernation is strong, this happens with lots of words. (Or was the influence from "rumination"?)
Oops, thank you.
Our tortoise, even though he's in a very comfortable climate controlled indoor pen, tries to dig a hole every year to do the same.
He's not very smart but he tries hard.
Now I'm wondering all kinds of things about their brain. Are they capable of forming memories, and would they retain those memories after a freeze/thaw cycle?
Effectively they're dead when they freeze. I'm assuming there's no brain activity.. Which means when they thaw they're being restored to life. I wonder if any other animals experience this
I would assume that just as a computer’s storage remains intact after a restart, these frogs’ brains have internal structure, synaptic connections etc that are preserved after a freeze/thaw cycle.
Reading about them, it seems they migrate in winter (like half a mile uphill), but the adults always return to the same breeding pond in spring, so that information is stored somewhere.
I'm not surprised. There have been studies that show caterpillars retain memories through metamorphosis into a butterfly (a process that basically liquefies them).
Hibernate and resume.
There are no pictures of the frogs in this article. For pictures (of thawed and frozen frogs) you can see: https://shakerlakes.org/frozen-frogs/
From the linked video: timelapse of the thawing process: https://youtu.be/pLPeehsXAr4?t=176
They also have a wiki, but not many photos. One photo is from Quebec.
The wiki also mentions that urea is produced, in addition to glucose, and both act as cryoprotectants.
https://en.m.wikipedia.org/wiki/Wood_frog
Looks like a normal (frozen) frog to me
cant even call that hibernation. There are other knock on advantages to bieng frozen solid, it would slow down and even kill a lot of infectious microbes.It may convey a certain life extension benifit. And threre is not much behavioral adaptation needed,frog gets chilly, snuggles under a leaf,freezes solid, gets defrosted 8 months later and wakes up hungry and horny, not bad.
> it would slow down and even kill a lot of infectious microbes
I wouldn't count on it killing them. The cryoprotectants in the frog's body don't discriminate; they'll protect foreign bacteria just as well as the frog's cells.
I should of elaborated, many of the issues associated with,"conventional hibernation" have to do with lethal infections aquired externaly while hibernating, damp, cold, ....mold as to the cryoprotectants ,side protecting microbes, clearly gut microbes and other internal flora ,would benifit......but ,big but, would a sneeky cryosuspension routine also include a freeze and clense cycle?, why not! and easy enough to verify,right!
> It may convey a certain life extension benefit.
I think it would be more interesting if it doesn't affect lifespan. It would be a really counter-intuitive result (to me).
> ...the wood frog’s liver produces large amounts of glucose that flushes into every cell in its body. This syrupy sugar solution prevents the cells from freezing...
All natural, no preservatives added, sweetened frog popsicles! Yummy!
I'm not even joking about this -- since frog legs are a thing people eat (taste kinda like chicken), I'm now incredibly curious what this would taste like if you "caught" these in their frozen state and cooked them.
Are we taking syrupy sweet meat? Or just a hint of it?
According to the video in https://shakerlakes.org/frozen-frogs, it's also full of urine. Not sure if any left after the cooking process.
Evolutionarily, amphibians are somewhat simpler than mammals, they're smaller than a lot of mammals and they don't live as long, so I suspect some of this is simply that "things that aren't there". They wouldn't have as many problems with advanced glycation end products because the temperature is so low. There's at least one other ice survival strategy: antifreeze proteins. The fir tree and a variety of arctic fish have these: https://pmc.ncbi.nlm.nih.gov/articles/PMC6691018/.
In all cases, I still don't understand how the membrane potentials are maintained or re-constructed in the thawing phase: any pointers?
I think there are threads in Michael Levin's work that suggest membrane voltage potential may be able to be 'encoded' to microtubule structures and converted back into voltage potentials later. I don't think it's firmly established or understood yet but seems like a promising area for research!
Perhaps because ice forms outside cells, freezing ions in place. Even if there was a very small area around ion channels that was liquid that equalized all ion concentrations with the cell, when the extra cellular fluid thaws the original concentrations would be pretty much restored
Could such a mechanism be used for interstellar travel ?
Of the frogs? Sure!
Someone tell Alcor about this.
How are they thawing from the inside out?
I really expected a wood(en) frog here, qualifying truly as a biological miracle. But the wood frogs are cool as well.
Oh god. This made me wonder, what is wood, anyway? And I've just come away much more confused.
Bamboo is a grass and doesn't come from a tree. Palm wood comes from palm trees, except palm tree trunks are apparently a totally different type of structure than other tree trunks, sounds closer to Papyrus. No growth rings, a fiber type structure. Is Papyrus wood?
Any plant matter above a certain density? I don't think that's it. Corn stalks aren't wood.
Man, I don't know. I am certain that it must be plant matter though, so yes, a wooden frog would be a biological miracle.
What's really going to bake your noodle later is that Corn is a grass, just like Bamboo.
My total armchair answer: It helps to think about trees as just giant shrubs.
Shrubs are considered "woody", but most definitely are not trees. There are plenty of trees which are close relatives of shrubs (like poison oak and the urushi tree).
So what's the difference between a grass and a tree? Walking the tree of life up from Poison Oak and Bamboo, we see we land at Monocotyledon and Eudicots. There's lots of non-woody and tough fibrous (i.e. woody) plans in both clades (palm trees are monocots, btw).
Wikipedia says if it is tough and fibrous and has growth rings it's wood:
https://en.wikipedia.org/wiki/Wood
So Bamboo, although coming from a grass and not a tree, is wood. Further reading down that page talks about density as a key quality of wood, and goes on to not definitively quality bamboo as wood or as non-wood but some are dense enough.
Ultimately, there's no super clean definition of wood is my take-away, between the technical and colloquial aspects. You can use bamboo in construction much like wood, if you cut off a bit of shrub and dry it out, it's a "stick" just as much as if you trimmed it off a tree. You can make paper out of all kinds of fibers.
It's worse than that. _Tree_ isn't even a well-defined thing.
> Trees are not a monophyletic taxonomic group but consist of a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight.[1]
[1]: https://en.wikipedia.org/wiki/Tree
I don't know a precise definition, but wood has many origins. Wood has evolved hundreds of separate times, including at least 38 separate times just on the Canary Islands. https://www.researchgate.net/publication/341287935_Multiple_..., https://www.pnas.org/doi/pdf/10.1073/pnas.2208629119?downloa...
Wood is secondary xylem produced by growth from the vascular Cambium. (Sometimes? I think the issue is that there’s more than one definition of wood depending on context …?). Growth rings?
But palm trees aren’t truly trees, right ? Just called trees…. They’re more of a tree like shrub? I think.
Trying to learn about this through claude was kinda funny.
Ask it to tell me about wood that doesn't come from trees, and it tells me about palm wood. I say, but doesn't that come from palm trees? It says palm trees aren't technically trees because their trunk isn't wooden.
Anyway, with your definition palm wood wouldn't be wood, and neither would bamboo. Feels like the vegetable/fruit thing though, there just isn't a perfect answer.
It's best to think of it as "tree-ing" or "to tree"
A really, really fantastic article: https://eukaryotewritesblog.com/2021/05/02/theres-no-such-th...
reminds me of the New Avengers episode "the eagle's nest" https://www.imdb.com/title/tt0659325/
> wood frogs spend the winter frozen
> syrupy sugar solution prevents the cells from freezing
So they don't freeze. This is click bait.
Why does it only count if the cells themselves freeze? Also, am I still allowed to play freeze tag, or do we need to rename that?
Can't tell if joking...
Nicely written article. A few pictures could have made it more interesting.
Ok, this is what you really wanted: https://www.bbc.co.uk/programmes/p091w1b3
Fascinating phenomena, thanks a lot for sharing!
I now know why I require so much sugar and sweets: I am a wood frog preparing for hibernation!
Not one photo of said frog.
Look, new rule: you write an article about frogs, you include a photo.
here's an illustration of one: https://image.non.io/e9078e7d-5eb4-4787-9fe2-d7068d01a4df.we...
this was really helpful! thanks!
But the article explains perfectly how they look like. White eyes, glucose filled cells, frozen solid as a rock. Bang it against a table, it's definitely frozen. Throw it back underneath those leaves.
Like the Tree Octopus?