What does fly society look like? The social structures of insects.
There are so many different reasons why people might want to draw. For some it is a way to express emotions, for others it is a hobby or an artistic expression, and there are those who just get really creative with their drawings. But the reason that flies draw is more than most people would believe—it’s not just for fun! In fact, flies have a very well-developed social structure that includes an elaborate system of communication and behavior. They can communicate with each other by knocking their heads against a surface (in the same way that humans knock on a door) and they have been observed to form intricate social structures within their colonies. Flies also have very intricate mating rituals and compete for food. Flies communicate with each other by using pheromones – chemicals that tell others of the same species about social statuses and behaviors. The first recorded documentation of the use of pheromones in insects came from Karl von Frisch, a Nobel Prize winner in 1973, when he found out that the honeybee was not just making up waggle dance but was actually communicating to other bees. The “dance” actually gave instructions on how to find the best sources of pollen and nectar, what direction to fly, and even when to return home. The honeybee waggle dance is unique because it combines very specific body movements with the ability to fly a specific path that ends at the food source.
Humans can communicate in many different ways including sounds, sights, and chemicals. Flies also use all these techniques depending upon their location—those that are in water tend to only use chemicals while those in air stick with sight and sound. The housefly for example uses its antennae to detect odors, while their compound eyes help them detect movement and determine the distance to their target. They also have tiny hairs on their feet that help them feel what is around them. Houseflies are not only interested in making contact; they want to know if you are worth their time. A housefly will fly towards a new object and then turn away if they don’t like the looks of it. If however they decide that you’re not a waste of time (they can tell by the sounds that you make) they will land on your arm and begin exploring. The first thing a fly will usually touch is your hair; this gives it information about how to respond to what it encounters next. Flies are very sensitive to light, smell, and touch. When you put your hand in a jar full of flies, the ones that enter your hand first will also be the ones that go for the food source. A fly is also quite a fast worker and can use its feet to run around on things at incredible speeds.
Fly society is primarily classified by age-grades, but it can be difficult to tell what age-group their social structure falls under unless you look closely at them or know them well. Just like humans they form friendships with individuals of their own age-grade. The age-grades of a fly are usually about a year apart and they are based upon pair bonds. The females tend to have many more eggs than the males, but many times the males still do most of the raising and caring for the young. The young (called larvae) hatch from the eggs in small sections called instars. These instars are each marked by their own color and can be differentiated from one another by how active or not they are. There are three stages to a fly’s life, but it is easier for most people to relate to that of an adult flies. The larva is a very small creature which has wings, but they are not attached to the body yet. Within each instar there will be one or more newly hatched larvae that have food sources and are capable of eating, and then a number of larval instars with fully formed wings. In the final instar all of the offspring have fully developed wings.
The responsibilities that flies take on while growing up vary greatly depending on where they live. They may be one of the first insects to start a colony, or may feed their larvae and raise them in an empty egg case for their entire life. Some flies may just return to the nest and observe the young as they grow, while others will leave them entirely and go out in search of their own food. The number of offspring that a fly will have can vary wildly. In one study only 4% of the flies produced more than 125 offspring, while another with large populations found that 30% were producing over 100 eggs per day. Each individual housefly can have about 500 eggs per brood; this means that a female will produce well over a quarter million eggs in her lifetime!
In order to keep track of their growing brood, most flies build something like an egg case for each one of their larvae. Some of these cases are very intricate and have a lot of material while others are very simple. In some species the males build the case, while in others it’s the females that do it. Sometimes when a male create a case the female will lay her eggs in it and then she will take on the responsibility of caring for those young. This means leaving her previous young to fend for themselves while she cares for her new offspring.
Male house flies sometimes have to protect their offspring from intruders which can cause a lot of stress on them and their families. This stress usually results in more aggressive habits and less likely to approach larger animals or people. This is good for people though, because flies will avoid things that are likely to be harmful to them. This can cause some problems for the colonies though; the fewer animals that they approach, the less likely they are to get their eggs protected. If a fly is too aggressive it will be killed or ejected from the colony by its peers.
House fly life expectancy depends upon many factors including where they live and how they behave. Their lifespan can be as low as one year if the resources in their environment are scarce, but conditions can allow them to live for up to three years or more.
Did you enjoy this little jaunt into the secret lives of flies? Why not leave a comment? Or like the subject matter and wanting a great movie to watch, check out the the 80’s classic “The Fly”, staring Jeff Goldblum and Geena Davis Here.