This is the classical situation retained in the commonly-dissected dogfish shark (a cartilaginous fish). The addition of a conus arteriosus to the heart of jawed vertebrates, a structure that damps out the pulsatile nature of the blood flow out of the ventricle, is held to reflect a higher blood pressure in jawed vertebrates over the condition in jawless ones.
© 2007-2010 Christine Janis, Professor of Ecology and Evolutionary Biology
Colleen Brogan '10, Student Technology Assistant
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