Differential rotation of the present and the pre-main-sequence Sun

We present a model for the differential rotation of the present Sun as well as a solar-type star during its pre-main-sequence evolution. The model is based on the mixing-length theory of convective heat transport and a standa rd solar model. The resulting rotation law is in good agreement with observ ations and only weakly dependent on the mixing-length parameter. For the pr esent Sun, the normalized horizontal shear decreases with increasing rotati on rate, but the total shear is roughly constant. We then follow the Sun's evolutionary track from the beginning of the contraction to the arrival on the ZAMS. While at art age of 30 Myr the total shear is very similar to tha t of the present Sun, it is much smaller on the Hayashi track.