Most sauropods kept their long necks roughly horizontal, like long living tubes feeding on low ferns and bushes. Brachiosaurus didn’t. Its front legs were taller than its back legs, and its neck pointed up - way up - so the head ended up about 40 feet off the ground. That’s the height of a 4-story building.
The advantage was treetop food no other dinosaur could reach. The cost was an absolute monster of a heart. Pushing blood that high meant Brachiosaurus needed a heart far stronger and bigger than anything alive today. Scientists estimate it weighed at least 400 pounds - more than a refrigerator full of blood.
It also probably ate around 800 pounds of plants every single day, just to keep all that body running.
