Figure 3From: Offspring pay sooner, parents pay later: experimental manipulation of body mass reveals trade-offs between immune function, reproduction and survivalPrediction of return rates by immune parameters. A) Heterophil/lymphocyte-ratio at second brood and B) change in agglutination from first to second brood for experimental and control skylarks that returned the year after and for birds that did not return. The interaction between return rate and treatment was significant in both cases (P = 0.01). Statistical analyses can be found in Results.Back to article page