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I'm not aware of any animal with more than one heart and I'm not aware of any scientific literature backing that sort of claim. Conversely, statements to the effect that there would be an insurmountable problem with sauropods holding their heads high are easy to find in real scientific literature.
you just haven't done your reading. here's a hint, get off the internet. i remember very distinctly when the issue of the cardiopulmonary system of a brachiosaurus was dealt with. i do believe they even had fossil evidence to support it.
I was trying to be polite the first time. If you're going to stick with this sort of ignorant bullshit, there's no real need for politeness.
There is no animal with more than one heart and no reason to believe there ever would have been. That would require that dinosaurs had been a totally separate creation from all other animals, which NOBODY believes, evolutionists, creationists, or anybody else other possibly than the people who write the Marvel comic books.
Moreover, a number of totally competent scientists have flatly stated that a sauropod dinosaur could not hold his head high due to the problems of the blood pressure which would be required to do so (in our present gravity).
Christopher McGowan (DINOSAURS, SPITFIRES, & SEA DRAGONS) goes into this in detail (pages 101 - 120). He mentions the fact that a giraffe's blood pressure, at 200 - 300 mm Hg, far higher than that of any other animal, would probably rupture the vascular system of any other animal, and is maintained by thick arterial walls and by a very tight skin which apparently acts like a jet pilot's pressure suit. A giraffe's head might reach to 20'. How a sauropod might have gotten blood to its brain at 50' or 60' is the real question.
Two articles which mention this problem appeared in the 12/91 issue of Natural History. In "Sauropods and Gravity", Harvey B. Lillywhite of Univ. Fla., Gainesville, notes:
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"...in a Barosaurus with its head held high, the heart had to work against a gravitational pressure of about 590 mm of mercury (Hg). In order for the heart to eject blood into the arteries of the neck, its pressure must exceed that of the blood pushing against the opposite side of the outflow valve. Moreover, some additional pressure would have been needed to overcome the resistance of smaller vessels within the head for blood flow to meet the requirements for brain and facial tissues. Therefore, hearts of Barosaurus must have generated pressures at least six times greater than those of humans and three to four times greater than those of giraffes."
In the same issue of Natural History, Peter Dodson ("Lifestyles of the Huge and Famous"), mentions that:
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"Brachiosaurus was built like a giraffe and may have fed like one. But most sauropods were built quite differently. At the base of the neck, a sauropod's vertebral spines unlike those of a giraffe, were weak and low and did not provide leverage for the muscles required to elevate the head in a high position. Furthermore, the blood pressure required to pump blood up to the brain, thirty or more feet in the air, would have placed extraordinary demands on the heart (see opposite page) [Lillywhite's article] and would seemingly have placed the animal at severe risk of a stroke, an aneurysm, or some other circulatory disaster. If sauropods fed with the neck extended just a little above heart level, say from ground level up to fifteen feet, the blood pressure required would have been far more reasonable."
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