Flies are a group of species of the order Diptera present throughout the world. Some of the best known are the house fly (Musca domestica), the fruit fly (Ceratitis capitata) and the vinegar fly (Drosophila melanogaster).
The fly life cycle consists of four stages: egg, larva, pupa and adult fly. Like most insects, they go through a series of morphological transformations that we know as metamorphosis. In this article on our site, we tell you everything that happens during the biological cycle of flies.
How do flies reproduce?
Human beings have always wondered how flies reproduce. Until the 17th century, it was thought that these appeared spontaneously in rotting meat. It was Francesco Redi who showed that this was not the case, but that every fly comes from an already existing one.
As in all insects, the reproduction of flies occurs only in their adult state. Before this happens, the male must court the female To do this, the male “sings” thanks to the vibration of his balancers or h alteres, structures that They are also used to control posture during flight. This is the reason for the characteristic sound of flies.
The female assesses whether the male's song and her scent (pheromones) are to her liking. If she decides she doesn't want to mate with this male, she keeps moving. But, if she believes that she has found the ideal mate, she stays put, so that he can begin copulation. The sexual act lasts at least 10 minutes.
How are flies born?
The life cycle of flies begins with the egg phase Therefore, we can say that these insects are oviparous. Or, at least, the majority. A small number of flies are ovoviviparous, that is, the eggs hatch inside the female and the larvae emerge directly during laying. In this section, we are going to focus on explaining how oviparous flies are born.
How are oviparous flies born?
After mating, the female looks for a good place to lay her eggs. This site depends on the species. The housefly lays its eggs in decaying organic debris, such as rotting meat. That's why they're always going through our garbage. The fruit fly, however, lays its eggs on apples, figs, peaches, etc. The number of eggs per clutch varies between 100 and 500 Throughout their lives, they can lay several thousand eggs.
In no time, the eggs hatch. From them come the fly larvae which are normally elongated and pale in colour. Colloquially, they are often called “worms”.
The main function of the larvae is to feed as much as they can to increase their size and develop properly. Food also depends on the species. As you may have already found out, housefly larvae feed on decomposing organic debris, while fruit fly larvae feed on fruit pulp. Surely, you have ever seen "coconuts" in a steak or worms in an apple. Now you know that they are actually flies.
The metamorphosis of flies
When they have eaten enough, the larvae are covered by a kind of capsule of a darker color, usually brown or reddish. This is what we know as pupa During this stage, the animal does not feed or move. The pupa appears to be inactive, but in reality metamorphosis is taking place.
Metamorphosis is the biological process by which the larva transforms into the adult fly During this period, its body differentiates into three parts: head, thorax and abdomen. In addition, the legs and wings appear. After these transformations, the adult fly leaves the pupa in the same way as butterflies. In the adult state, reproduction takes place.
The duration of the metamorphosis of flies depends on the temperature In summer, when it is hot, this process occurs quickly. During the winter, however, the fly remains as a pupa until the heat returns. For this reason, flies do not bother us in the coldest seasons. Although it is also true that, if they shelter well, many of these insects can survive in their adult form until spring.
If this topic calls your attention, here we leave you more Animals that undergo metamorphosis in their development.
How long do flies live?
The question of how long flies live is not easy to answer, since it depends on their species and their living conditions. However, we can affirm that the life cycle of flies usually lasts between 15 and 30 days, thus being considered one of The 10 animals that live the least.
The better the climate and its diet, the longer a fly can live. It seems like a short time, but it is more than enough to lay thousands of eggs. This efficiency has allowed them to colonize the entire planet and adapt to all possible environments.
Other curiosities about flies
Flies aren't just those pesky animals we're all thinking about. Many species are even very beneficial for humans For this reason, we will tell you some curiosities about flies that show that they are much more interesting than we think.
- Some are pollinators: Many flies are pollinators, like bees and butterflies. That is, they feed on nectar during their adult stage, transporting pollen from one flower to another. Thus, they contribute to the reproduction of plants and, therefore, the formation of the fruit. Among these flies is the family Calliphoridae (blue and green flies).
- Predatory Flies: Many other species of predatory flies also exist. The vast majority feed on other insects or arachnids that are harmful to humans. For example, hoverflies (family Syrphidae) are predators of pests such as aphids and whiteflies. These flies physically resemble bees and wasps.
- They are eaten by other animals: Other species of flies are very annoying and can transmit diseases. However, they are the food of many animals, such as spiders, frogs, toads, birds and even fish. Their existence is essential for the life of other animals and, therefore, for the proper functioning of ecosystems. Therefore, we recommend driving them away, whenever possible, using natural remedies.
