Found this wood frog, Rana (Lithobates) sylvatica, yesterday near an ephemeral pond at Hildacy Farm Preserve, Media, Pennsylvania. A common frog, but still rather amazing when you look at its distribution … they can be found above the Arctic Circle in Alaska. [Pause for amazement.] That means they can tolerate being almost completely frozen in their hibernaculum for as long as 7 months, tolerating temperatures as low as -18 degrees Celsius (~0 degrees F). No other amphibian is found that far north. Part of their trick is jacking up the glucose concentration of muscles. If you chipped one out of the ice and grilled it quickly, it would taste a lot sweeter (13 fold!) than one grilled during the summer. But they also jack up their urea content so I’m not sure it would be a treat. #woodfrog #ranasylvatica #hildacyfarmpreserve #naturallandstrust #mediapa #frog #amphibian #ephemeralpond #lithobatessylvaticus #freezing #antifreeze #biology #hibernaculum #cryoprotection (at Hildacy Farm Preserve)