comment on this calibration


 node name
Uria     Look for this name in NCBI   Wikipedia   Animal Diversity Web
  recommended citations Smith, 2015
  node minimum age
2.6 Ma
The transgressive marine sequences that outcrop at Tolstoi Point, and from which the Uria remains were recovered, are interpreted as equivalent to the Bigbendian and Colvillian stages and the absolute ages have been established at 2.6-3.0 Ma on the basis of stratigraphic and biostratigraphic correlations (Brigham-Grette and Carter 1992; Olson, in press).
  node maximum age
0 Ma
none specified.
 primary fossil used to date this node 
CASG 71892
Uria lomvia, NO REFERENCE
Location relative to the calibrated node: Crown

[show fossil details]
     Locality: Tolstoi Point
     Geological age: Piacenzian, Pliocene, Neogene, Cenozoic

  phylogenetic justification
Referred to Uria lomvia based upon apomorphies of the coracoid and humerus (Olson, in press). Although the specimen has not been included in a phylogenetic analysis, it would likely be an operational equivalent of specimens of Uria lomvia scored by Smith (2011a) and the referral of that specimen to Uria lomvia has not been questioned.
  phylogenetic reference(s)
Smith, N. A. and J. A. Clarke. 2011. An alphataxonomic revision of extinct and extant razorbills (Aves, Alcidae): a combined morphometric and phylogenetic approach. Ornithological Monographs 72:1-61.
 tree image (click image for full size) 
tree image
Figure 2 from Smith (2015).