We investigate the impact of starspots on the evolution of late-type starsduring the pre-main sequence (pre-MS). We find that heavy spot coverageincreases the radii of stars by 4-10%, consistent with inflation factors ineclipsing binary systems, and suppresses the rate of pre-MS lithium depletion,leading to a dispersion in zero-age MS Li abundance (comparable to observedspreads) if a range of spot properties exist within clusters from 3-10 Myr.This concordance with data implies that spots induce a range of radii at fixedmass during the pre-MS. These spots decrease the luminosity and $T_{\rm eff}$of stars, leading to a displacement on the HR diagram. This displacement causesisochrone derived masses and ages to be systematically under-estimated, and canlead to the spurious appearance of an age spread in a co-eval population.
展开▼
