how do they do it? argiope sac

[Galapoheros]

I was on my mountain bike and saw an argiope eggsac, I would've left it there but I wanted to check to see if the slings survived the winter temps here. It got down into the mid teens here. How do they keep from freezing in there? My reasoning might be wrong but isn't it no warmer in there than a blanket? People say, "This blanket is really warm, but it's literally not warm, you heat it up with your body heat, the ones that hold the heat better that's generated by our bodies are the ones we call "warm". Spiders don't generate their own heat to heat up the sac, so how do they keep from freezing? Or do they have some kind of natural anti-freeze when that young, or when they are eggs? Click on the pic for a vid if you want to see them crawling around.

 

[zonbonzovi]

I have wondered about this, too. If I'm reading this correctly, the space between the cocoon & flocculent layer normalize the interior of the eggsac? I didn't know sacs had this "microscopic gatekeeper". Neat. Thanks for posing the question!

http://www.sciencedirect.com/scienc...28755f72b844ec3542aa9af37fce16a4&searchtype=a

 

[Galapoheros]

Yeah that was pretty cool, too bad the clip is about the higher temp side, and I'm not paying $31.50 just to see if it answers the "freeze" thing. This sac was under a metal rail in the shade. Last night I was thinking of the probable high insulating qualities of the sac and wondered if sewing 1000's between cloth material, maybe after cutting them in a certain way, would make a really good blanket. These are the kinds of things that keep me from falling asleep:8o

 

[zonbonzovi]

I used to laugh at people and their high thread count sheets...until someone gave me a set. Now if you can find a means to process those sacs into clean fiber, you could set the textile world on fire! I don't think anyone's been able to do so yet?

 

[Moltar]

Lots of arthropods have some sort of "antifreeze" in their body fluids that prevents hard freezing.

 

[presurcukr]

Lots of arthropods have some sort of "antifreeze" in their body fluids that prevents hard freezing.

Most Coccinellidae (ladybugs/ladybird/ladybird beetles/lady beetles/ladyclock, lady cow, and lady fly) can survive a freeze and "thaw" unharmed in the spring!!Actulay they have trehalose sugar, that depresses the freezing point of the insect. Insects that pass the winter exposed to cold have an extra amount of trehalose, so their anti-freeze is more effective.And some lady beetles congregate in large groups to pass the winter in a state of hibernation. Conserved heat from the mass of lady beetles raises their temperature slightly, helping to protect them from freezing.