Exploring thermal ecology in the field

Temperature is a fundamental driver of biology, affecting physiology, phenology and species interactions in complex ways. While lab studies can isolate the effects of temperature under controlled conditions, insects commonly experience more complex thermal environments in nature. Here, I describe two recent projects that investigated different aspects of thermal ecology in the field. The first experiment aimed to separate the effects of daytime vs. nighttime warming on insect growth and survival in a natural community. The second experiment studied the effects of temperature on the likelihood and fitness costs of a predator avoidance behavior, i.e. dropping off a host plant in response to attack. Both experiments examined the consequences of temporal and spatial thermal variation at the scale of individual insects and in the context of complex natural communities. In both cases, the complexity of field conditions allowed for unexpected insights. A third study attempted to bring some key aspects of environmental complexity from the field back into the lab, using an array of microscale environmental chambers to create a factorial combination of temperature, moisture and photoperiodic conditions to test hypotheses about how insects integrate multiple phenological cues. Together, these projects (and projects like them) are attempting to further explore the complexity of thermal ecology in the field and suggest ways to combine field and lab studies in the future.