On Being a Cold Bug

When confronted with the brutally cold weather of winter and harsh outdoor living conditions as a result of it, it is extremely difficult for a human being to spend an entire winter outside and survive. I can't imagine being stuck outside for all of winter because I wouldn't make it very long, but in this world for insects they have no other option. Perhaps if only I could borrow some of the unique adaptations insects refer to in order to overcome the coldest time of the year.

If there was a tree big enough then maybe I could choose to overwinter inside of it just like mourning cloak butterflies hibernate inside hollow trees. Another option, if I had wings, would be to learn from the shivering moth and shiver as a way to warm my muscles, heat up to overcome the cold, and fly away. However, I find these options too easy, and unfair, if I am to fully take on the cold weather.

One of the best characteristics that I could adopt from specific insects is their ability to supercool. As shown from the woolly bear caterpillar, supercooling is a way to reduce the freezing point of the insect's blood and prevent ice formation by converting glycogen into glycerol (an alcohol) and sorbitol (a sugar). As a result, the caterpillar will appear frozen but once thawed out is alive and well. Once a caterpillar is warmed it will come back to life, but this depends for other insects such as horned beetles since their glycerol level is very high. It takes a couple of days for them to move normally again once the proper temperature is present.  The presence of glycerol is also found to shield eastern tent caterpillar moth eggs.

                                                             
                                                                  Woolly bear caterpillar

Supercooling is an effective method to survive the winter but any contact with ice crystals will provide nucleation sites for ice crystal formation resulting in death. Even though stinkbugs and yellow jacket wasps are very effective at surviving through supercooling I wouldn't want to take any chances.

                                                    
                                                     Sharp and deadly edges of ice crystals

I think my best technique for surviving the winter would come from northern Eurosta larvae. The northern larvae have the same advantages for supercooling, but they also release a protein into their blood that promotes freezing. Although counterintuitive, this protein prevents the insect from supercooling. Freezing may not sound like the best option but it is more of a way to help the insect survive if the temperature was to become too cold for glycerol to tolerate. This way you have the help of the protein, to tolerate freezing if it were to occur, as well as the dual properties of glycerol to reduce the probability of freezing and damage from ice crystals if they were to occur. I think this would be the most effective and safest way to overcome the winter.

Images found from:
www.thefeaturedcreature.com
commons.wikimedia.org