The role of temperature in reproductivity trade-offs and life span in a winter-adaptive arthropod

Abstract

Temperature plays a key role in the development and population maintenance of arthropods, especially for those living in cold environments. In the temperate zone, one of the most common soil-dwelling arthropods is Collembola. Instead of tracking warm and thermal temperature ranges, some Collembola species are psychrotrophic, i.e., they are well-adapted to lower temperatures. We investigated Desoria ruseki (Isotomidae), a Collembola species widely distributed in high latitudes in the Palearctic and adapted to winter, to determine the crucial temperature conditions for the sustainability of field populations of this winter-adaptive arthropod. We incubated the adult individuals of the species at six temperatures ranging from -5°C to 30°C for 98 days. We found that 0°C and 5°C, corresponding to the temperatures when the species is active in the field between late autumn (November) and early spring (April), were the best temperatures for the survival of the lab individuals. However, they died out quickly at temperatures above 20°C without laying eggs. In contrast, the species could lay eggs between 0℃ and 15℃: the higher the temperature was, the earlier they laid eggs. In addition, longer periods were needed for juveniles to hatch from eggs at lower temperatures. Our study indicates that, rather than colder conditions, hotter environments are likely to be more detrimental to the winter-adaptive Collembola species, thereby suggesting major threats to biodiversity at high latitudes under the current global warming regimes.