The origin of the ratites, large flightless birds from the Southern Hemisphere, along with their flighted sister taxa, the South American tinamous, is central to understanding the role of plate tectonics in the distributions of modern birds and mammals. Defining the dates of ratite divergences is also critical for determining the age of modern avian…

The ratites have stimulated much debate as to how such large flightless birds came to be distributed across the southern continents, and whether they are a monophyletic group or are composed of unrelated lineages that independently lost the power of flight. Hypotheses regarding the relationships among taxa differ for morphological and molecular data sets, thus…

Chickens and the great flightless emu belong to two distantly related orders of birds in the carinate and ratite subclasses that diverged at least 80 million years ago. In the first ZOO-FISH study between bird species, we hybridized single chromosome paints from the chicken (Gallus domesticus) onto the emu chromosomes. We found that the nine…

Existing animal models of femoral head osteonecrosis, while displaying varying levels of concordance with early histopathologic features of the human disorder, generally fail to progress to end-stage mechanical collapse. A new animal model of osteonecrosis is here introduced, utilizing the emu (Dromaius novaehollandie). These animals’ bipedality and their high activity level represent a much more…

Interference in radioimmunoassays (RIAs) was frequently encountered during endocrinological studies of the emu (Dromaius novaehollandiae). Interference was greatest when serum was cloudy or opaque. Such samples appeared seasonally, in spring and summer during the phase of fat deposition, and in the winter when females were laying. These poor quality samples did not allow accurate measurement…

Six emu hatchlings were non-invasively measured for electrocardiogram (ECG) from their chest wall using flexible electrodes, and the instantaneous heart rate (IHR) was determined from ECG throughout the first week of post-hatching life. Although the baseline heart rate (HR) was low, approximately 100-200 beats per min (bpm), compared with chick hatchlings, the IHR fluctuated markedly.…

The amino acid sequence of a single polypeptide chain, B-4, from fowl feather barbs has been determined. The B-4 chain was found to consist of 96 amino acid residues and to have a molecular weight of 10206 in the S-carboxymethylated form. The N terminus of this protein was an N-acetylserine residue. The B-4 protein contained…