Compare the circulatory systems of different vertebrate groups and explore how during evolution the structure of the heart has changed drastically from the relatively simple two-chambered heart of fish, to the three-chambered heart of amphibians and reptiles, and the four-chambered heart of mammals and birds. Interesting adaptations include the heart of the crocodile, which changes its circulatory pattern depending on whether the animal is diving underwater or on the surface. The heart of a mammalian fetus shows a circulatory pattern reminiscent of that of the crocodile diving underwater.
This Click and Learn supplements the 1998 Holiday Lectures on Science.
