Efficient fish not faint-hearted

Access through your institution Buy or subscribe THE BLOOD CIRCULATION SYSTEMS OF CERTAIN AIR-BREATHING FISHES AND MOST REPTILES APPEAR TO BE PRIMITIVE AND INEFFICIENT. BUT THERE MAY WELL BE

GOOD REASON THAT THEY ARE DESIGNED THE WAY THEY ARE, AND THE PRINCIPLES CONCERNED COULD INFORM CLINICIANS WHO TREAT HEART DISEASE. A primary function of blood circulation is to provide

oxygenated blood to the tissues of the body. Why, then, in some air-breathing fishes, does oxygenated blood flow from the lung to the heart and then to the gills, rather than flowing

directly to oxygenate the body? And why do the hearts of most reptiles retain an only partially divided ventricle, given that mixing venous and arterial blood reduces oxygen delivery to the

body? Writing in the August issue of _Paleobiology_, Colleen Farmer1 proposes an intriguing function for these puzzling circulatory patterns — that they provide oxygenated blood to the heart

muscle itself. This is a preview of subscription content, access via your institution ACCESS OPTIONS Access through your institution Subscribe to this journal Receive 51 print issues and

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which are calculated during checkout ADDITIONAL ACCESS OPTIONS: * Log in * Learn about institutional subscriptions * Read our FAQs * Contact customer support REFERENCES * Farmer, C.

_Paleobiology_ 23, 358–372 (1997). Google Scholar  * White, F. N. in _Biology of the Reptilia_ (eds Dawson, W. R. & Gans, C.) 275-334 (Academic, New York, 1976). * Johansen, K. &

Burggren, W. W. in _Hearts and Heart-Like Organs_ (ed. Bourne, G.) 61-117 (Academic, New York, 1980). * Hicks, J. W. & Wang, T. _J. Exp. Zool._ 275, 204–216 (1996). Google Scholar  *

Wang, T., Krosniunas, E. H. & Hicks, J. W. _Am. Zool._ 37, 12 –22 (1997). Google Scholar  * Kohmoto, T. _et al. Circulation_ 95, 1585–1591 (1997). Google Scholar  * Horvath, K.

A., Mannting, F., Cummings, N., Shernan, S. K. & Cohn, L. H. _J. Thorac. Cardiovasc. Surg._ 111, 1047–1053 (1996). Google Scholar  * Gans, C. _Forma et Functio_ 3, 61–104 (1970). Google

Scholar  * Liem, K. F. _Am. Zool._ 28, 739–759 (1988). Google Scholar  * Graham, J. B. _Air-Breathing Fishes: Evolution, Diversity, and Adaptation_ (Academic, New York, 1997). Download

references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * the Biology Department, and the Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, 01003,

Massachusetts, USA Elizabeth Brainerd Authors * Elizabeth Brainerd View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and

permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Brainerd, E. Efficient fish not faint-hearted. _Nature_ 389, 229–230 (1997). https://doi.org/10.1038/38381 Download citation * Issue Date: 18

September 1997 * DOI: https://doi.org/10.1038/38381 SHARE THIS ARTICLE Anyone you share the following link with will be able to read this content: Get shareable link Sorry, a shareable link

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