Gregori's Polar-Bird

Polarornis gregorii

(Chatterjee, 1985)

   Polarornis gregorii is the antarctic equivalent of Hesperornis regalis.  It is a diving, fish-eating bird that will sit on top of the water, diving under occasionally to snap at a fish or crustacean it sees below itself.  However, although both birds share the basic body type of all fot-propelled divers, they are totally unrelated.  Unlike, H. regalis , P. gregorii possesses functional wings, its legs are not splayed so far to its sides, and its lightly-built skull terminates in a pointed, completely toothless bill. Polarornis gregorii is, in fact, a loon.

    The avian fauna of the Cretaceous is widely varied, with many different lineages of toothed, clawed, and otherwise weird birds living side by side with familiar loons and shorebirds.  However, the extinction event that will destroy the larger dinosaurs will also decimate bird populations, and only one group of beaked, clawless birds will survive, spreading from the southern hemisphere and diversifying into a world-spanning monopoly on feathered flight.  For now, however, P. gregorii is only one of many, a diving fish-eater that dwells on the coasts of temperate Antarctica, quite similar to its distant descendants, which will live in almost exactly the same fashion, separated by a hemisphere and 70 million years.

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Other sites containing pertinent information:

• The Rise of Birds by Sankar Chatterjee.  Published in 1997 by Johns Hopkins University Press.
• "The Morphology and Systematics of Polarornis, a Cretaceous Loon (Aves: Gaviidae) from Antarctica)", by Sankar Chatterjee, published in The Proceedings of the 5th Symposium of the Society of Avian Paleontology and Evolution Bejing, 1-4 June 2000, edited by Zhonghe Zhou and Fucheng Zhang by Science Press, Beijing, China, 2002.