Comparative study of mathematical models for the relationship between water temperature and brood development time of Gammarus fossarum and G. roeseli (Crustacea: Amphipoda)

SUMMARY. 1. The relationship between water temperature ( T°C ) and brood development time (d days for embryonic development time plus 'post-hatch time') was investigated experimentally using animals from four populations of Gammarus fossarum (populations 1–4) and two populations of G. roeseli (populations 5 and 6) in Austrian streams.
2. Eleven mathematical models were examined as suitable functions to describe the relationship between d and T . The models were compared with respect to their goodness-of-fit and suitability for further quantitative, statistical analyses of intra- and interspecific differences between natural populations of G. fossarum and G. roeseli .
3. Statistical analyses were performed with logarithmically transformed values of d , in order to provide homogeneous variances between the different constant temperatures used. The following three-parameter model was found to be the most suitable for the data:
This equation was fitted in its linear form: