The heart of the dugong (Dugong dugon) and the west indian manatee (Trichechus manatus) (Sirenia)

✍ Scribed by U. Rowlatt; H. Marsh

• Book ID: 102904140
• Publisher: John Wiley and Sons
• Year: 1985
• Tongue: English
• Weight: 992 KB
• Volume: 186
• Category: Article
• ISSN: 0362-2525
• DOI: 10.1002/jmor.1051860109

✦ Synopsis

Thirty-eight dugong (Dugong dugon) hearts and 28 Florida manatee (Trichechus manatus) hearts were obtained from stranding programs in Australia and the United States. In addition to a double ventricular apex, a feature that has astonished scientists since the eighteenth century, the hearts of both animals have a double subvalvular conus and a dorsal left atrium. The heart lies in a vertical plane at right angles to that of the completely dorsal, symmetrical lungs. The dugong heart has a deeper interventricular cleft and a more conical left ventricle. The latter features may be part of a general morphological trend toward specialization for a more energetic aquatic existence. The presence of a bulbous ascending aorta in the manatee but not in the dugong is without explanation.