Surviving the Bitter Cold

Vannessa Peters

23 May 2019

Introduction

"There is something infinitely healing in the repeating refrains of nature - the assurance that dawn comes after night, and spring after winter."

- Rachel Carson

Where do all the bugs and insects go during winter? There prescience is evident during the warmer times of the year, but do they disappear or die as soon as their summer vacation is over? How they actively live their lives has been more studied than when they go on vacation. I think it is just as important to understand what their smaller proportioned bodies, wings, and offspring go through during the rougher times. This blog is going to inform many biological and ecosystemic ways to survive temperatures far beyond their compacity.

Temperature

Insects are fairly poikilothermic; this means that their body temperatures correlate, if not match, the temperature of their surroundings. Each stage of development for insects sets a different temperature range for them to survive, and, if the insects aren’t comfortable with their temperature, they will move to where it’s warmer. A good portion of insects are able to withstand ice developing in their bodies. Temperature fluctuation can strongly influence the speed of aging or the pace for activity. Due to the rapid water evaporation in smaller bugs, the larger the bug, the longer is takes the bug to freeze. There tends to be more insulation in bigger bugs with hair, scales or shields (Romoser and Stoffolano, 1998).

Behind the Biology

The knowledge of activity, behavior, and location of insects is more understood and familiar when in higher temperatures (spring and summer) than that in lower temperatures (fall and winter). If a species of a given insect isn’t slowly acclimated to the drop in temperature, then, due to their body’s lack of preparation, they will go into a cold shock. More often than not a cold shock will either result in injury or supercooling which is when their bodies spontaneously freeze. Hemolymph proteins (lipoproteins) are used to confine the formation of ice in specific areas of the insect body’s to where they can still survive with little harm and prevent supercooling. Others tend to have genetics that provide them these “antifreeze proteins”/”thermalhysteresis proteins”. These proteins pause their development but push the ice that is being formed to as much of an outer layer as possible. This allows them to remain alive but kind of put into hibernation. There are also bacteria found in some species abdomen to help regulate the supercooling side effects. Sometimes cocoons are used as protection against the cold. Cold hardening is another option for insects to use for self-preservation; glycerol helps to make this possible. Both cold hardiness and diapause are necessary stages for insects to survive the winter. Diapause is a endocrine-mediated dormancy that only happens to insects that are within certain stages of their development at that time. There is a change in food storage that occurs. This helps the metabolism to slow down so that the insect may have a ong lasting amount of nutrition that it needs. Cold temperatures can be avoided by being underneath the snow and remaining undergrounds. Humidity can affect the survivial of most species. Clustering is an option for colonized insects so that they can try and contemperate heat within their bodyies (Lee and Delinger, 1991).

Habitats:

Some insects hibernate in various damp and dim conservative shelters to keep them hidden and comfortable during the winter months. There have been other informative reports stating that some larvae hibernate while frozen in bodies of water. An example of this is the Wyeomyia smithii (a.k.a. the pitcher plant misquito). Although spring is remarkably well known for the burst of new life, some insects even hibernate gravid (Matheson, 1966).

Factors

Overwintering is how an organism can last through the winter. There is a lot of variables to consider for how the temperature effects particular species. Some of these variables are how close the area is along the equator, what the altitude is for their habitat, the weather for their daily terrain, air flow, precipitation approximations, formations of water, soil texture and pH, and the moisture within all those surroundings. The more dehydrated an insect is approaching winter the better; being dehydrated helps them not to form crystallization of water in their head, thorax and abdomens. Lipids help preserve heat and create more of a barrier between the inside of the insect and its snowy surroundings. Cold hardiness can be described as an organism being able to survive low temperatures: some are tolerant and others are intolerant. Stabilizing proteins and electrolytes, maintaining cell volumes, the ability to help keep fluidity, can all be achieved by crypoprotective functions (Leather et al, 1995).