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Name: David
Status: educator
Grade: K-3
Location: NC
Date: July 2008

How do maggots get inside a sealed container?


The maggots and/or their eggs must be in the container before the container gets sealed.


They get inside when an adult fly laid its eggs there *before* the container got sealed. If you look up the word "abiogenesis", you'll see that a long time ago certain materials were thought to "magically" create various organisms... hay into mice, dew into aphids, meat into maggots, etc. This idea has now been proven wrong for over 100 years.

You can imagine where these ideas came from. In the case of maggots, there is enough time between the laying of the eggs (an event which is easy to miss, due to the fly's small size) and the arrival of the maggots, that it might be hard to make the connection. However, if you wait long enough (and provide air, food, and moisture), and prevent their escape, you'll ultimately be able to see the maggots pupate (turn into a darker, semi-rigid "pupa") and hatch into adult flies. That is, if it doesn't gross you out first!

P. Bridges

You are asking the same question that Redi asked in the 1500s! Maggots hatch from the eggs of flies which are microscopic so can't be seen. They must have been present before the jar was sealed.


They don't. The maggots (or fly eggs) are either in there before you seal it, or it isn't really sealed. Read online about 'spontaneous generation' for more details.


Maggots are the larval stage of the common house fly. At some point prior to sealing the container, the fly has had the opportunity to lay eggs in the growth medium. Otherwise, no maggots would appear.

Vince Calder


To get into a sealed container, maggots or fly eggs have to be in the container before it is sealed.

Look up Louis Pasteur to see the experiments he did to prove this is true.

Take care.

R. Avakian

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