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tokens: a revised model for a He shell detonation Type Ia SN. In any case, we think it is likely that the Mn/Fe, Ni/Fe, Cu/Fe, and Zn/Fe enhancements in G 112-43/44 and the three α -poor stars are caused by element contribution from a special kind of SN to pockets of gas from which these stars were formed. Such inhomogeneous mixing of SN products is more likely to affect the chemical evolution of dwarf galaxies than higher-mass systems because in lower-mass galaxies the gas has a relatively long cooling time, resulting in episodic star-formation bursts ( Revaz et al. 2009 ; Venn et al. 2012 ). In view of this, it is interesting that G 112-43/44, as a member of the Helmi streams, was probably born in a dwarf galaxy and that one of the three α -poor halo stars with enhancements of Mn/Fe, Ni/Fe, and Zn/Fe also has Helmi stream kinematics 6 , as seen from Fig. 1 . G 4-36 and BPS BS 16920-17 have kinematics similar to stars belonging to the Gaia -Enceladus population, but BPS CS 22966-43 lies in the Helmi box with positive V Z . Not all stars belonging to the Helmi streams have unusual abundances. Roederer et al. (2010) made a detailed abundance analysis of 12 subgiant and giant stars with Helmi stream kinematics, and Gull et al. (2021) recently added seven stars to this work. Within the typical errors of the abundance determinations (0.10–0.15 dex), [Mn/Fe], [Ni/Fe], [Cu/Fe], and [Zn/Fe] agree with the [X/Fe]-[Fe/H] trends of Galactic halo stars. The stars investigated, however, have [Fe/H] ≲ −1.5 and high [ α /Fe] ratios (e.g., [Mg/Fe] ∼ 0.3), so it remains to be seen if the Helmi streams contain a population of low- α stars at higher metallicities and if some of these stars have over-abundances of Mn, Ni, Cu, and Zn relative to Fe. Low- α stars are well known in dwarf galaxies (see the review by Tolstoy et al. 2009 ). In the Sculptor dSph galaxy, for example, [Mg/Fe] shows a declining metallicity trend from [Mg/Fe] ≃ 0.4 at [Fe/H] = −1.8 to [Mg/Fe] ≃ −0.2 at [Fe/H] = −1.0. Interestingly, Skúladóttir et al. (2017) find indications of a cosmic scatter in [Zn/Fe] of the Sculptor stars (i.e., from about −0.6 dex to +0.4 dex) and a positive correlation between [Ni/Fe] and [Zn/Fe]. At a distance of ∼85 kpc, the giants observed in Sculptor are, however, faint (17.0 V 18.5), and the errors of [Zn/Fe] are of the order of ±0.3 dex. It will require more precise [Ni/Fe] and [Zn/Fe] values as well as an improved precision of [Mn/Fe] values ( North et al. 2012 ) to verify if stars with enhanced Mn/Fe, Ni/Fe, and Zn/Fe ratios are present in Sculptor. Another interesting case is the ultra-faint dwarf galaxy Horologium I, in which Nagasawa et al. (2018) found three very metal-poor ([Fe/H] ∼ −2.5) giant stars that are α -poor ([Mg/Fe] and [Ca/Fe] ≃ 0.0) and enhanced in [Mn/Fe] by about 0.4 dex relative to Galactic halo stars. However, their [Ni/Fe] ratios seem to be normal, and their Cu and Zn abundances were not determined. Again, we need more precise abundances,