The life-cycle of a fly can be an interesting subject to observe.
Things Required:
1 quart jar (1 litre)
Nylon stocking
rubber band
Banana
Directions:
Peel the banana and place the fruit inside the open jar. Leave the jar open and undisturbed for 3 to 5 days. Observe the jar daily. When 5 to 10 small fruit flies are seen inside the jar, cover the top with the stocking. Secure the stocking over the mouth of the jar with a rubber band.
Leave the flies in the jar for 3 days; then release all of them. Recover the jar with the stocking.
Observe the jar for 2 weeks.
This Is What Happens:
Within a few days, maggots can be seen crawling around. Later, small capsules replace the maggots and finally new flies emerge.
Science Behind It:
The fruit flies are attracted to the smell of the ripening fruit. The flies laid eggs on the fruit which developed into the larvae, called maggots. The maggots go through a resting stage called the pupae. Pupae are similar to the cocoon formed by caterpillars. The last stage is the emerging adult fly and the cycle starts over again.
