A. Location of the MMSt and adjoining striatum (MSt) in a schematic section from the budgerigar brain atlas at http://www.brauthlab.umd.edu/atlas.htm (Brauth SE; Jarvis et al., 2013). (B) In situ hybridized FoxP2 mRNA in which the MMSt can be found at (B) D20, D35, D60, and (C) in adults, D>120 (all birds are male). Sections of similar male brains show in situ hybridized FoxP1 mRNA in (D) and (E). Scale bar in (E) = 4 mm. Abbreviations: H, Hyperpallium; MD, dorsal Mesopallium; MV, ventral Mesopallium; N, Nidopallium; Bas, Basorostral pallial nucleus; MMSt, Magnocellular nucleus of the medial striatum; MSt, Medial striatum; LSt, Lateral striatum; VSt, Ventral striatum.