Putting a Dino on a Scale – a “Weighty” Task

We can visualize how tall certain dinosaurs probably were by reassembling their skeletons, but how do we determine the body weight of a dinosaur? For about 25 years, paleontologists have used a statistical model to estimate the weight of giant dinosaurs. Recently, Colorado State University researchers have pointed out that this model may be seriously flawed – leading them to believe those dinosaurs may only be half as heavy as originally thought.

Statistical Estimation

The weight of a dinosaur must be estimated, since there are no full remains to place on a scale. Here is a basic formula:

• Calculate volume of the dinosaur based on skeletal structure
• Use average weight of bone and tissue per unit volume to calculate mass
  
  

A statistical model, developed in 1985, can be used to calculate mass of large animals, but seems to be more accurate for smaller animals. The model has also been used to calculate brain and egg size.

Problem Discovered

Researchers at George Mason University have found many errors in the calculations related to some of the largest animals. The issue came to life when researchers used the model to calculate the weight of living animals that can actually be weighed on a scale to verify the results; animals such as a hippopotamus and elephant were used in these tests. The statistical equation "greatly overestimated" the weight.

A Potential Solution

Researchers are working on a new model based on bone dimensions. The concept is that bigger animals require bigger bones to support them. Research indicates that dinosaurs might have been less bulky than originally thought. If so, muscle mass, movement, eating and breathing habits would all have been different as well.

For example, the Tyrannosaurus Rex could have been smaller. Smaller size could mean faster speed and agility. Better hunting skills would in-turn lead to an increased choice in prey, too.

You can see how your favorite dinosaur sizes up on this website.

Resources:

http://www.physorg.com/news164866282.html

http://www.sciencedaily.com/releases/2009/06/090621195620.htm

http://www.uky.edu/KGS/education/dinosaurs_weight.htm

http://dinosaurs.suite101.com/article.cfm/dinosaurs_smaller_than_thought