USEFUL

Last year at a biology convention
A researcher was heard to mention
“We don’t use lab rats anymore”
You could have heard a pin hit the floor
“We use “Wannabees” now instead”
"Really why is that?” someone said
"Well, three reasons to be truthful
Firstly “Wannabees” are more plentiful”
Second, the lab assistants don't get
Attached to them or even upset,
And thirdly there are one or two
Things that even a rat won't do”