71–80 of 145 posts
> Nobody yet understands what starts the wood frog’s heart after being frozen and inert for the entire northern winter. To me, that's the most fascinating part of the (already quite fascinating) story. Frog is frozen solid, there is no (to our knowledge) heartbeat or brain activity. It thaws and something happens that gets it going again. I have trouble imagining what that mechanism could even look like. Tiny portion…
> Nobody yet understands what starts the wood frog’s heart after being frozen and inert for the entire northern winter. To me, that's the most fascinating part of the (already quite fascinating) story. Frog is frozen solid, there is no (to our knowledge) heartbeat or brain activity. It thaws and something happens that gets it going again. I have trouble imagining what that mechanism could even look like. Tiny portion…
The frog is not frozen solid.
> Nobody yet understands what starts the wood frog’s heart after being frozen and inert for the entire northern winter. To me, that's the most fascinating part of the (already quite fascinating) story. Frog is frozen solid, there is no (to our knowledge) heartbeat or brain activity. It thaws and something happens that gets it going again. I have trouble imagining what that mechanism could even look like. Tiny portion…
my poor knowledge of biology says it's a deeply unsatisfying "heart beats when enough of the body has thawed for it to beat." If the heart depends on the brain at all in frogs.
So starting and stopping the heart in a controlled manner is pretty interesting, because it has to be well-timed, and there are few obvious and reliable inputs to control it, especially when thawing.
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!)
> Nobody yet understands what starts the wood frog’s heart after being frozen and inert for the entire northern winter. To me, that's the most fascinating part of the (already quite fascinating) story. Frog is frozen solid, there is no (to our knowledge) heartbeat or brain activity. It thaws and something happens that gets it going again. I have trouble imagining what that mechanism could even look like. Tiny portion…
Maybe something like a bit flip but for neurons happens in the frog's brain from the sun's radiation or something. Or the elasticity of the heart and muscles.
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!)
It's a bit of a fantasy that we might find a perfectly well preserved dinosaur in a glacier somewhere.
Earlier quoted context omitted.
> 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 ve…
Earlier quoted context omitted.
Maybe something like a bit flip but for neurons happens in the frog's brain from the sun's radiation or something. Or the elasticity of the heart and muscles.
If it gets frozen in a heavily contracted form, unthawing it will trigger at least one half-beat: could that be enough to restart it?
Did not think that my early morning would be spend trying to imagine how thawing a frog works. :)
> Nobody yet understands what starts the wood frog’s heart after being frozen and inert for the entire northern winter. To me, that's the most fascinating part of the (already quite fascinating) story. Frog is frozen solid, there is no (to our knowledge) heartbeat or brain activity. It thaws and something happens that gets it going again. I have trouble imagining what that mechanism could even look like. Tiny portion…
Maybe it is that thawing happens in reverse with the extremities, then the rest of the system thawing, with the heart being last. Would be a biological advantage in this case for the heart to be centrally located.
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.