Bulletin Banner

Return to 4th Quarter 2019 articles.

Dandy Designs title

The title of this article is Necks Too Impossible.

Barosaurus-rendering and skeleton

Skeletal remains of the Barosaurus show that its head would have towered fifty feet (more than 15 meters) above the ground. No one denies the size of the animal. The problems come when we start looking at its anatomy.

The animal with the longest neck today is the giraffe. To get blood to its brain, a giraffe has a systolic blood pressure (mmHg) as high as 350. For humans, anything over 140 is considered high. To create that much pressure, the giraffe’s heart weighs about 25 pounds (11.3 kilograms). A human heart weighs about 11 ounces (310 grams). For a Barosaurus, the heart would have to weigh tons. Also, the blood vessels would have to be extraordinarily thick. It is difficult to believe that such conditions are possible.

Years ago, some scientists proposed that Barosaurus had eight hearts. They suggested a heart like ours pumped blood from the body to the lungs and back. Then they suggested a complicated series of seven other single-chamber hearts. One would be above the primary one with one-way valves to boost the blood into the neck. Above the second heart, the artery would divide into two branches. Three hearts along each branch would pump the blood to the next heart until it reached the brain. This arrangement would reduce the dinosaur blood pressure so that the systolic pressure would max out at about 180.

This proposal will always remain as just another imaginative idea because there may never be any way to test it. Each heart's pressure would have to be critically adjusted to move the blood to the next level. If the blood pressure went too high, it would damage the delicate valves of the next heart. If the animal ran, each heart would have to speed up, but not at the same rate.

The point is that the anatomical complexity and the number of critical parameters required would make this dinosaur’s blood pressure system virtually impossible to happen by chance. They can better be explained by design.

Picture credits:
Left: https://en.wikipedia.org/wiki/Barosaurus#/media/File:Barosaurus_lentus1.jpg; right: … File:Barosaurus_mount_1.jpg