干旱区生态环境知识资源中心

The activity of the thermophilous ant Proformica longiseta has been studied in a Mediterranean high-mountain environment. An analysis has been made of the biotic and abiotic variables involved, the location of and conditions surrounding the activity, as well as the strategies used by the ant to remain active at high temperatures. The results of this study indicate that the maximum activity occurs during the middle hours of the day and that the variable which most influences daily activity is temperature, especially at the soil surface. With respect to the biotic variables, the availability of food and the demand for food by the larvae strongly correlate with activity. The time outside the nest is usually spent in vegetation searching for food. This activity continues even when the temperature of the soil surface exceeds 58 degrees C. To tolerate these temperatures, the ant not only has a high resistance to heat (critical thermal maximum = 51.1 degrees C), but also increases the speed of its movements and resorts to thermal refuges. The present work contributes data on the biology of this highly thermophilous species, which is also capable of tolerating a long, hard winter and then developing within a short vegetative period.