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We present the results of our analysis of the RR Lyrae (RRL) variable starsdetected in two transition-type dwarf galaxies (dTrans), ESO294-G010 andESO410-G005 in the Sculptor group, which is known to be one of the closestneighboring galaxy groups to our Local Group. Using deep archival images fromthe Advanced Camera for Surveys (ACS) onboard the Hubble Space Telescope (HST),we have identified a sample of RR Lyrae candidates in both dTrans galaxies [219RRab (RR0) and 13 RRc (RR1) variables in ESO294-G010; 225 RRab and 44 RRc starsin ESO410-G005]. The metallicities of the individual RRab stars are calculatedvia the period-amplitude-[Fe/H] relation derived by Alcock et al. This yieldsmean metallicities of <[Fe/H]>_{ESO294} = -1.77 +/- 0.03 and <[Fe/H]>_{ESO410}= -1.64 +/- 0.03. The RRL metallicity distribution functions (MDFs) areinvestigated further via simple chemical evolution models; these reveal therelics of the early chemical enrichment processes for these two dTransgalaxies. In the case of both galaxies, the shapes of the RRL MDFs arewell-described by pre-enrichment models. This suggests two possible channelsfor the early chemical evolution for these Sculptor group dTrans galaxies: 1)The ancient stellar populations of our target dwarf galaxies might have formedfrom the star forming gas which was already enriched through "prompt initialenrichment" or an "initial nucleosynthetic spike" from the very first massivestars, or 2) this pre-enrichment state might have been achieved by the endproducts from more evolved systems of their nearest neighbor, NGC 55.

The Early Chemical Enrichment Histories of Two Sculptor Group Dwarf Galaxies as Revealed by RR Lyrae Variables