Fig. 1. (A) Experimental estradiol injection protocol to determine the pattern of vitellogenin production in response to the treatment. (B) Experimental injection and resting metabolic rate (RMR) protocol to determine the potential metabolic cost of yolk precursor production. The numbers represent the days into the treatment, with the white sections symbolizing daytime and dark sections symbolizing night-time. The arrows represent either RMR measurement, injection or blood sampling time.