Figure 2.

Overview of three current theories on the evolution f the dorsal pallium in amniotes. In each row, a drawing of a transverse hemisection through the telencephalon of a developing bird is shown to the left, and two drawings of transverse hemisections through the telencephalon of a developing mammal are shown to the right, with the far right drawing being the more caudal one and through the level of the amygdala. In the top row, the structures are identified (see abbreviations below). The second row illustrates the ADVR-lateral neocortex hypothesis of Reiner (1993) and Butler (1994), derived from the equivalent cell hypothesis of Karten (1969). The third row illustrates the ADVR-claustroamygdalar hypothesis, variations of which are supported by Bruce and Neary (1995), Stredter (1997), Puelles and co-workers (Puelles et al., 2000; 2007; Medina et al., 2005a,b), and Martínez-Garcia et al., (2002;. The fourth row illustrate the ADVR-lateral neocortex plus claustroamygdalar field homology hypothesis of Butler and Molnár (2002). The colors and fill patterns are used to indicate comparative structures for each hypothesis. Since the piriform cortex is not shown as a separate entitiy in the mammalian figures but rather is included in the LP/VP regions, it is not colored in most cases. All of these hypotheses basically agree on a discrete homology of most or all of piriform cortex across amniotes. Abbreviations: Cpi, Piriform cortex; HA, Hyperpallium apicale; LP, Lateral pallium; LNC, Lateral neocortex (i.e., collothalamic-recipient neocortex); LPCA, Lateral pallial cortical area; M, Mesopallium; MNC, Medial neocortex (i.e., lemnothalamic-recipient neocortex); MP, Medial pallium; N, Nidopallium; P, Pallidum; S, Septal nuclei; St, Striatum; V, Lateral ventricle; VP, Ventral pallium. (Modified by A. Butler from Butler and Hodos, 2005)Figure modified and kindly provided by AB Butler and reproduced with permission from John Wiley and Sons, Hoboken, New Jersey.