Book 5, Question 18
Fast or Slow? Why Do Scientists Argue About T. Rex Speed?
Nobody could time a Tyrannosaurus rex, so scientists use clues like leg bones, footprints, and computer models. Different methods give different answers, and that leads to friendly arguments. Disagreeing and testing ideas is a normal part of science.
From the book
Page from A Million Whys Book 5
More fun facts
- Older estimates said T. rex could run between 11 and 33 miles per hour.
- A newer computer model found that T. rex could probably reach only about 12 miles per hour.
- Any faster, and its bones might have shattered.
- So the mighty T. rex was likely limited to a brisk walk, slower than the fastest human runners.
- Scientists often guess dinosaur speed from the space between fossil footprints.
- Experiments with birds walking through mud show footprint-based guesses can be up to 2.5 times too fast.
- Another study suggests T. rex usually walked at about 3 miles per hour.
Sources: National Geographic, Science News Explores, Smithsonian Magazine
Questions kids ask
Could T. rex catch a car?
No. Scientists now think T. rex could only reach about 12 miles per hour, much slower than a car.