: an act of showing someone how something is used or done : demonstration. 1  I saw a demo on how to use the computer program. 2  The salesman gave us a demo of the vacuum cleaner, and it seemed to work very well. [+] more examples [-] hide examples [+] Example sentences [-] Hide examples 3
If however, you are talking about some maggots in a bowl of wet food (either canned food or dry food which got wet or which you deliberately added fluid to) it is a different matter. Maggots come from flies eggs and they take some set period of time to hatch from the eggs.
After between 4 and 10 days of this feeding frenzy, maggots ready themselves for the next stage: pupa. The maggots typically migrate to a high and dry location to begin the pupa stage. The maggots make a reddish-brown shell around themselves. They stay in that protective environment, the pupa, for three to six days. They are developing into flies.