The physiological and evolutionary significance of cardiovascular shunting patterns in reptiles.
@article{Hicks2002ThePA, title={The physiological and evolutionary significance of cardiovascular shunting patterns in reptiles.}, author={James W Hicks}, journal={News in physiological sciences : an international journal of physiology produced jointly by the International Union of Physiological Sciences and the American Physiological Society}, year={2002}, volume={17}, pages={ 241-5 } }
The morphology of the reptilian heart results in the mixing of oxygenated and deoxygenated blood (cardiac shunts). In birds and mammals cardiac shunts are detrimental, but in reptiles this condition is often considered a derived trait, conveying important physiological functions and favored by natural selection. Alternative views are advanced suggesting that, in reptiles, cardiac shunts represent either an ancestral condition or an embryonic trait.
81 Citations
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The evidence supports the alternative hypothesis that cardiac anatomy and resulting cardiac shunts in nonavian reptiles are plesiomorphic traits that do not negatively impact the primary function of the cardiovascular system.
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In situ cardiac perfusion reveals interspecific variation of intraventricular flow separation in reptiles
- BiologyJournal of Experimental Biology
- 2016
It is concluded that relatively minor structural differences between non-crocodilian reptiles result in the fundamental changes in cardiac function, whereas some (turtles, anacondas, bearded dragons) show a large capacity for cardiac shunting.
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- 2009
These findings provide a molecular mechanism for the evolution of the amniote ventricle, and support the concept that altered expression of developmental regulators is a key mechanism of vertebrate evolution.
Cardiovascular shunting in vertebrates: a practical integration of competing hypotheses
- BiologyBiological reviews of the Cambridge Philosophical Society
- 2019
It is argued that deposing the ‘monolithic’ view of shunting leads to a more nuanced view of vertebrate cardiovascular systems, and suggests new paradigms for testing the function of shunts.
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- 2004
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