Question

In summer, certain lizards have a low critical minimum temperature of 2.5ºC. In winter, these same lizards have a critical minimum temperature of -1.2ºC. The lizards do not freeze at this critical minimum temperature, even though this is below the freezing point for their blood. They are able to move under the snow while in this supercooled state at a temperature slightly above -1.2ºC. Hypothesize as to how the lizards are able to keep from freezing at temperatures below 0ºC.

Answer 1

I'm not certain if this applies to lizards, but I have heard of special proteins that allow certain organisms to withstand cold temperatures.

You may want to talk a look here: http://en.wikipedia.org/wiki/Antifreeze_protein
"...AFPs bind to small ice crystals to inhibit growth and recrystallization of ice that would otherwise be fatal."