How Tall Is A Brachiosaurus? Imagine it? You’ve taken your family on a picnic. You are enjoying your cold fried chicken and lemonade in the shade of a lush forest full of tall, green trees. Thanks to the sure-to-be-invented-soon technology of time travel, you and your family are visiting North America during the late Jurassic period. That’s about 153 million years ago, give or take a million years.
You sit on your red and white checked blanket while the kids chase each other around the massive tree trunks. Suddenly the ground shakes and you hear rustling in the leaves high above your head. You call the kids back and carefully shift your picnic away from the noise, It’s not just lunchtime for your family; it’s also lunchtime for the brachiosaurus, one very large sauropod.
Measuring between 60 and 70 feet from the tip of its nose to the end of its tail, the brachiosaurus easily dines on leaves that are 30 feet above the ground. It could likely reach higher if it held its long neck completely vertical. Doing this stresses the large creature’s cardiovascular system, though, so this is not a position the brachiosaurus maintains for extended periods.
You continue to watch the dinosaur eat, now from a safe distance away. As it subsists exclusively on plants, you don’t need to worry about it deciding your family looks like a tasty snack, but given that it weighs about 50 metric tons taking care not to get stepped on is a good idea. At this point, you also notice another interesting feature of its anatomy.
The forelegs of the _brachiosaurus altithorax _are longer than its hind legs. In fact, the generic name _brachiosaurus_ is Greek for “arm lizard”. The specific name _altithorax_ is Greek for “deep chest”. The long front legs, short hind legs, and barrel chest make the shape of the brachiosaurus’s body oddly similar to that of a bulldog. A bulldog with a very long tail can poke its head into a fourth-floor window.
The brachiosaurus seems to be a gentle creature, despite its immense size, and of course, the kids want to take it home. Unfortunately, not only do the rules of time travel technology prohibit this, some quick math tells you that keeping a dinosaur as a pet would get very expensive very quickly.
A creature of that size needs to eat upwards of 800 pounds of food every day. The smattering of trees in your backyard is not going to cut it, and you’d have to have a lake dug to provide adequate drinking water. Not to mention all the collateral property damage that an animal longer and heavier than a London city bus would cause just by walking around.
You are just about to explain this to the children when they point and scream “it’s a tyrannosaurus!” You follow their gaze and sure enough, a very large carnivore has taken an interest in your picnic. “No, kids,” you explain patiently. “Tyrannosaurus won’t be along until the Cretaceous period, and that’s not for another 80 million years or so. The dinosaur that is about to eat us is an allosaurus. We should definitely be heading home, though.” And with that, you say goodbye to the brachiosaurus and make the leap back to your own time.