For those of us who observe the academic calendar in the United States, the end of August means the end of summer and the beginning of a new year. It’s a time of general excitement and new possibilities. And while we are caught up in the craziness that comes during this season, we are generally unaware that winter is coming – at least for those that live in the northern hemisphere. Somehow, even though I know it is coming, I am never quite prepared for its arrival. My unpreparedness is partly because day-to-day busyness distracts me from these sorts of things, but there are other reasons. One is that the timing of seasons is changing and becoming less predictable because of global climate weirding. Another reason is that modern lighting, heating and cooling systems, and agricultural practices have lessened the need to prepare for seasonal changes in daylight, temperature, and food abundance.
I am fully aware that not all living things (or even all people) share the privilege I have of paying more attention to holiday seasons or sports season than to seasons marked by significant changes in average daily temperatures and food availability. Most living things have little control over their surroundings, and they rely on a variety of adaptations in order to survive seasons when the environment is inhospitable. Insects, birds, reptiles, mammals, and plants that live in temperate regions adjust their metabolic rates, behaviors, activity levels, living spaces, and, in some cases physical appearances in order to survive the challenges of winter. Some birds, insects, and mammals escape from winter by migrating to warmer places with a more hospitable climate. Other living things shelter in place in some form of suspended animation.
Many insects fit into this second category, and they overwinter in diapause, a type of dormancy that is similar to, but not exactly like, hibernation.