[α/Fe] vs. [Fe/H] for J1907 (large red circle with error bars), compared to relevant samples. Small open gray triangles show MW stars (Venn et al. 2004; Reddy et al. 2006). Black filled circles represent the Sgr dSph main-body stars (Monaco et al. 2005; Sbordone et al. 2007, and in prep.; Hansen et al. 2018a). Green large symbols show the average values for globular clusters associated with Sgr dSph: the square is Ter 7; the star is Pal 12; the diamond is NGC 6715; the triangle is Arp 2; the X is NGC 5634; the circle is Ter 8; and the cross is NGC 5053 (Sbordone et al. 2005, 2015; Cohen 2004; Carretta et al. 2010, 2014; Mottini et al. 2008). [α/Fe] is here defined as the simple average of [Mg/Fe], [Si/Fe], and [Ca/Fe], or any subsample of them available for each specific star. A reference error bar of ±0.15 dex on both axes is also plotted.