Bird eggs
THE FIRST RECORD OF BIRD EGGS FROM THE EARLY OLIGOCENE (ORELLAN) OF NORTH AMERICA ROBERT M. CHANDLER AND WILLIAM P. WALL
In overall geometry (elongation average, bicone average, asymmetry) and eggshell porosity, and texture compares closest to the egg of the Limpkin, Aramus guarauna. An extinct limpkin, Badistornis aramus Wetmore, has been described from essentially the same locality (using identical stratigraphic, lithologic, and age criteria). Although B. aramus did have slightly longer tarsometatarsi than A. guarauna, overall the birds would be of very similar body size and weight. It can be surmised that these two closely related species of North American limpkins would have had eggs of similar size and shape. There are other extinct birds represented in the fossil record during the early Oligocene such as a guan and a quail (Galliformes: Cracidae, Phasianidae, respectively), a hawk (Falconiformes: Accipitridae), and an extinct relative of the modern seriema (Bathornithidae), but all of these living birds have eggs of a very different shape and/or size.
There is a published record of an early Miocene possible duck egg from South Dakota (Farrington, 1899). However, the collecting data is simply "region of the Bad Lands" and, therefore, the age is also questionable. O'Harra (1920:143) cites Farrington's report and states that there are other badlands bird eggs in museums, as was also noted by one of our reviewers, but as yet these are unstudied and unpublished specimens and are, therefore, not science.
In overall geometry (elongation average, bicone average, asymmetry) and eggshell porosity, and texture compares closest to the egg of the Limpkin, Aramus guarauna. An extinct limpkin, Badistornis aramus Wetmore, has been described from essentially the same locality (using identical stratigraphic, lithologic, and age criteria). Although B. aramus did have slightly longer tarsometatarsi than A. guarauna, overall the birds would be of very similar body size and weight. It can be surmised that these two closely related species of North American limpkins would have had eggs of similar size and shape. There are other extinct birds represented in the fossil record during the early Oligocene such as a guan and a quail (Galliformes: Cracidae, Phasianidae, respectively), a hawk (Falconiformes: Accipitridae), and an extinct relative of the modern seriema (Bathornithidae), but all of these living birds have eggs of a very different shape and/or size.
There is a published record of an early Miocene possible duck egg from South Dakota (Farrington, 1899). However, the collecting data is simply "region of the Bad Lands" and, therefore, the age is also questionable. O'Harra (1920:143) cites Farrington's report and states that there are other badlands bird eggs in museums, as was also noted by one of our reviewers, but as yet these are unstudied and unpublished specimens and are, therefore, not science.
Taxa of birds ranked by abundance
Anatidae?