A magnitude-limited sample of nearly 9000 early-type galaxies in theredshift range 0.01<=z<=0.3 was selected from the Sloan DigitalSky Survey (SDSS) using morphological and spectral criteria. Thefundamental plane relation in this sample isRo~σ1.49+/-0.05I-0.75+/-0.01oin the r* band. It is approximately the same in the g*, i*, and z*bands. Relative to the population at the median redshift in the sample,galaxies at lower and higher redshifts have evolved only a little. Ifthe fundamental plane is used to quantify this evolution, then theapparent magnitude limit can masquerade as evolution; once thisselection effect has been accounted for, the evolution is consistentwith that of a passively evolving population that formed the bulk of itsstars about 9 Gyr ago. One of the principal advantages of the SDSSsample over previous samples is that the galaxies in it lie inenvironments ranging from isolation in the field to the dense cores ofclusters. The fundamental plane shows that galaxies in dense regions areslightly different from galaxies in less dense regions.