Physiological Stress Mediates the Honesty of Social Signals
Figure 4
Relationship between corticosterone (pg/mm) in feathers and changes in comb area (mm2) of male red grouse between C1 and C2, according to treatment.
a) T0: control implanted males; b) T+: testosterone implanted males. Parasite treatments: P0: purged of worms; P+: challenged with T. tenuis infective larvae.