FIGURE 2. Phylogram of alcid relationships showing calibrated nodes 7-15 (modified from Smith, 2011a, figure 1.26). Numbered nodes in red correspond to the following calibrations: (8) divergence of Alcidae from Stercorariidae; (9) divergence of Aethiini from Fraterculini; (10) divergence of Fratercula arctica from Fratercula corniculata; (11) divergence of Cepphus carbo from Cepphus columba; (12) divergence of Synthliboramphus hypoleucus from Synliboramphus craveri;divergence of Synthliboramphus hypoleucus from Synthliboramphus craveri; (13) divergence of Brachyramphus marmoratus from Brachyramphus brevirostris; (14) divergence of Alle alle from Uria; (15) divergence of Uria lomvia from Uria aalge; (16) divergence of Alca torda from Pinguinus impennis.