Where should you run an experiment?
Science experiments in the laboratory may not be the best answers.
BIG IDEA: When you do a science experiment, it’s important to record the setting of the experiment. Why? Because it may affect the results.
When scientist Henry Astley was studying at Brown University in Rhode Island, he read that in the laboratory, bullfrogs could jump 4 feet 3 inches (1.3 meters).
One day, Henry’s supervisor, Tom Roberts, read in the Guinness Book of World Records that Rosie the Ribeter had jumped 21 feet 5 and 3/4 inches in her1986 winning triple-jump at the Jumping Frog Jubilee®. That was an average of over seven feet per jump. Tom and Henry decided to attend the 2013 Jumping Frog Jubilee® in Angels Camp, CA to gather more information.
They set video cameras up and filmed 3124 frogs jumping, recording over 20 hours of video.
The Jumping Frog Jubilee® provided information on far more frogs than they had ever had in the laboratory. This meant their sample size was larger.
They measured two types of frog jumps
First were frogs jumped by the professional frog jockeys. They brought their own frogs that had been chosen because they were good jumpers. The frog jockeys knew how to lunge at the frog to make it jump farther. These frogs regularly jumped six to seven feet per jump.
Second were frogs jumped by amateurs, or people who just rented a frog. They knew very little about the frogs or how to encourage the frogs to jump farther. Their frogs only averaged 3.6 feet per jump, similar to those in the lab.
Henry, Tom, and the other scientists concluded that the biggest difference was the frog jockey. The jockeys learned over the years how to encourage the frogs to jump farther. They believe that lunging at the frog makes the frog think a large predator is after them. The jockey’s lunge triggers a flight response, the frogs trying to escape the predator. In scientific language, they discovered a variable that they hadn’t known existed.
BIG IDEA: Scientific experiments are affected by many variables. For example, if you change the setting, the results might be different. Sometimes, scientists don’t know all the important variables.
They also realized that studying or observing animals in a laboratory may be misleading. The laboratory isn’t always the best place for an animal to show the behavior that’s being studied. For bullfrogs, the Jumping Frog Jubilee® was the best place to show how far they jumped. Or, maybe they jump even farther in the wild when threatened by an actual predator. No one knows.
Astley, H. C., Abbott, E. M., Azizi, E., Marsh, R. L., and Roberts, T. J. (2013) Chasing maximal performance: A cautionary tale from the celebrated jumping frogs of Calaveras County. Journal of Experimental Biology, 216, 3947-3953. doi:10.1242/jeb.090357