Fig. 2: Timeline of the artificial size selection experiment on free-living house sparrows conducted in parallel on two islands in Norway starting in year 2002 (1st year). Adult birds were captured each winter for 4 years and selected for either longer or shorter tarsus length (each selection event showed with a solid black arrow). Telomere lengths (TL) were measured on nestling cohorts produced in the subsequent summer breeding season (showed as dotted grey arrows). Birds that were not removed during the artificially selection stayed in their populations, and survival and recruit production were monitored until all sampled birds were assumed to had died.
Table 1: Number of sampled offspring (n =566) in each artificial selection category (1: both parents artificially selected; 0.5: one parent subject to artificial selection; 0: no parents artificially selected, i.e. unselected) from year 2002-2006 in two island populations selected for larger (high ) and smaller (low ) tarsus length, respectively. Unknown genetic parents were assumed not to have been artificially selected.