Name:_________________________________
Science 7 / Great Neck South Middle School
Date:______________
Period:_____
Francesco Redi’s Famous Experiment
In the 1600’s, the Theory of Spontaneous Generation was a popular belief which
stated that living things could arise from non-living matter. Francesco Redi, an Italian
scientist living in Florence in 1670, wished to know if the maggots of flies (little white
worms that hatch from flies’ eggs) really came from decaying meat as people popularly
believed. Redi doubted it. He could not believe that living maggots could come from
dead, decaying meat. Instead of speculating about the problem, he began to look for
evidence to support an observation of his: he noticed that meat became wormy (full of
maggots) after flies had hovered over the meat for some period of time.
He placed four large flasks with different meat in each of them, closing and
sealing them. He placed four other large flasks with meat in each of them, leaving them
open to the air. He observed flies entering and leaving the open containers; the meat
became wormy. But in the four closed containers, he observed not a single maggot.
He tried another experiment with jars of meat covered only by a fine net that
allowed air to enter. Flies were soon attracted. Redi noticed that no maggots were in
the meat, but maggots were found moving about on the net’s surface. In Redi’s own
words, “I never saw any worms (maggots) in the meat, though many were to be seen
moving about on the net-covered frame. These, attracted by the odor of meat,
succeeded at last in penetrating the fine meshes and would have entered the vase had I
not speedily removed them.”
(1) State the problem that Redi set out to solve: (form of a question!)
(2) What did Redi need to know/do before he formulated a hypothesis?
(3) Write his hypothesis as an IF, THEN, BECAUSE statement:
(4) What was different between his first and second experiments?
(5) What observations did he make for his second experiment that would be considered
“data”?
(6) State a conclusion for Redi’s famous experiment: (did he prove or disprove the
Theory of Spontaneous Generation?)