Figure 1.

Growth of Schistocephalus solidus plerocercoids in Gasterosteus aculeatus. (a) Parasite weight (mean±s.e.) and (b) growth rate given as fold increase in average weight of parasites relative to previous time point. Dotted line indicates 50 mg standard parasite weight, the potential threshold for infectivity of definitive bird host, which was reached after 45 days (arrow). Growth rate at day 7 post-exposure was calculated based on weight measurements of procercoids isolated from copepods at the day of exposure (n=20 at day 0).