comment on this calibration

Fratecula arctica

 node name
Fratecula arctica     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Smith, 2015
  node minimum age
4.2 Ma
The Early Pliocene Yorktown Formation has been assigned an age of 4.4 ± 0.2 Ma based on K/Ar dating of the Orionina vaughani assemblage zone, and correlated with planktonic foraminifera Zone N19 (Hazel, 1983).
  node maximum age
0 Ma
none specified.
 primary fossil used to date this node 
USNM 490887
Fratercula aff. arctica, Olson and Rasmussen, 2001
Location relative to the calibrated node: Stem

[show fossil details]
     Locality: Lee Creek Mine
     Stratum: Yorktown Formation
     Geological age: Zanclean, Pliocene, Neogene, Cenozoic

  phylogenetic justification
Although never included in a phylogenetic analysis, specimens referred to Fratercula aff. arctica by Olson and Rasmussen (2001) and Smith et al. (2007) were scored into the morphological phylogenetic data matrix of Smith (2011a) and were determined to be operational equivalents of the extant exemplars of Fratercula arctica that were included in that combined phylogenetic analysis. Fratercula arctica and Fratercula corniculata have been recovered as sister taxa to the exclusion of the Tufted Puffin Fratercula cirrhata in analyses of morphological and molecular sequence data (Moum et al., 1994; Friesen et al., 1996; Thomas et al., 2004; Pereira and Baker, 2008; Smith, 2011a,b).
  phylogenetic reference(s)
Smith, N. A. 2011a. Systematics and evolution of extinct and extant Pan-Alcidae (Aves, Charadriiformes): combined phylogenetic analyses, divergence estimation, and paleoclimatic interactions. PhD Dissertation. The University of Texas at Austin. 748pp
Olson, S. L., and P. C. Rasmussen. 2001. Miocene and Pliocene birds from the Lee Creek Mine, North Carolina. Smithsonian Contributions to Paleobiology, 90:233-365.
Smith, N.A., Olson, S.L., and Clarke, J.A. 2007. First Atlantic record of the puffin Cerorhinca (Aves, Alcidae) from the Pliocene of North Carolina. Journal of Vertebrate Paleontology, 27:1039-1042.
 tree image (click image for full size) 
tree image
Figure 2 from Smith (2015).