events	initial capture	first sampling (S1)	second sampling (S2)	third sampling (S3)
dates	25 Sep ±5 days	10 Oct ±5 days	20 Oct ±5 days	27 Oct ±2 days
procedures	Purging of T. tenuis worms	experiment start		experiment end
		hormone implants
		parasite challenges
measurementsa		T. tenuis parasites		T. tenuis parasites
		testosterone	testosterone	testosterone
		comb area	comb area	comb area
		MDA	MDA
		TAS	TAS

^aWe measured parasites at S1 (using faecal samples) and S3 (using direct worm counts) to check that the parasite purging conducted at S0 had been effective (S1) and to check that parasite challenges were effective (S3), respectively. We did not measure parasites at S2 because it takes 10–15 days for T. tenuis larvae to develop into measurable, egg-producing worms using faecal samples. Not all parameters (parasites, testosterone, MDA and TAS) could be measured for all individuals at each sampling time, due to lack of sample material (faecal samples or plasma), so sample size varies between treatment groups and sampling times.