How Evolved are the Mass Donor Stars in Cataclysmic Variables

Recent spectroscopic observations have identified several cataclysmic variables non-solar metal abundances. We present theoretical models which examine the level of core evolution expected for CV secondaries prior to contact. Our results indicate that few secondary stars evolve past 10% of their main sequence lifetime prior to the initiation of mass transfer; a result which is in agreement with present day observations. Thus, the non-solar metal abundances observed must be due to nuclear burning by-products accreted by the secondary star during common envelope sweeping prior to initial contact or ejecta collected during classical nova outbursts.