Figure 2.

The relationship between early-life telomere length (at 10 days post-hatching) and (a) longevity (months seen alive), and (b) lifetime reproductive success (total offspring produced across the lifetimes) of 104 house sparrows (Passer domesticus) who bred at least once. The sexes are separated by colour (48 females are red and 56 males are black) and their separate linear regressions indicated with solid lines and 95% confidence limits by the shaded areas. Significance (see text) in (a) was assessed using a Cox regression and in (b) using a GLM with a negative binomial distribution. (Online version in colour.)