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We have used UVES on VLT-UT2 to take spectra of 15 red giants in theSculptor, Fornax, Carina and Leo I dwarf spheroidal galaxies. We measure theabundances of alpha, iron peak, s and r-process elements. No dSph giants in oursample show the deep mixing abundance pattern seen in nearly all globularclusters. At a given metallicity, the dSph giants exhibit lower [el/Fe]abundance ratios for the alpha elements than stars in the Galactic halo. Thiscan be caused by a slow star formation rate and contribution from Type Ia SN,and/or a small star formation event (low total mass) and mass dependent Type IISN yields. Differences in the even-Z [el/Fe] ratios between these galaxies, aswell as differences in the evolution of the s&r-process elements areinterpreted in terms of their star formation histories. Comparison of the dSphabundances with those of the Galactic halo reveals some consistencies. Inparticular, we find stars that mimic the abundance pattern found by Nissen &Shuster (1997) for metal-rich, high R_max, high z_max halo stars, supportingtheir suggestion that disrupted dSph's may explain up to 50% of the metal-richhalo. A comparison with the metal-poor Galactic halo reveal no consistenciessuggesting that the majority of the metal-poor Galactic halo could not havebeen formed from objects similar to these dSph. Finally, we use the dSphabundances to place new constraints on the nucleosynthetic origins, includingCu and Mn which are more consistent with metallicity dependent SN yields thanthe more commonly assumed SN Ia production.Comment: 37 pages, 12 tables, 14 figures, accepted by AJ for Feb 200

VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies. I. Nucleosynthesis and Abundance Ratios