The idea was floated by a specialist in flies, a South African dipterist who was tired of how little understanding there was of these unloved insects. Subsequently, last fall, dipterists attending their world congress declared 2019 to be the international Year of the Fly! The intention was to raise public awareness to the diversity and beauty of these insects as well as to their ecological and social importance. It’s also an opportunity to promote the work of men and women captivated by the buzzing and surprising insects – although in Québec, only a handful of women can take pride in the very distinctive title of dipterist!
Big flies and little ones
Diptera are insects having just one pair of wings. This group includes the “true” flies, such as the domestic fly, as well as the frailer ones, like mosquitoes and Chironomidae. To this point, over 160,000 species of fly have been described in the world. In Canada, more than 9,600 have been identified, but specialists reckon the number could be twice as high. The smallest species, Megapropodiphora arnoldi, measures 0.395 mm. It was named in honor of Arnold Schwarzenegger because of its extremely enlarged forelegs. At the other end of the scale, the females of the largest species, Gauromydas heros, reach a maximum length of 70 mm.
These insects, through their lifestyles, perform important ecological services for the human species:
- in feeding on nectar and pollen, bee flies and syrphid flies contribute to the pollination of plants. Thus, without the tiny Ceratopogonidae of the Forcipomyia genus, there would be no chocolate, because these flies (1 to 3 mm) are the only ones able to penetrate the complex flowers of cacao trees and introduce the pollen needed for their fecundation.
- a great majority of adult flies as well as their larvae serve as food for fish, birds and small mammals. In turn, predatory or parasitoid Diptera contribute to the control of numerous other species of insects that prey on crops and forests.
- in feeding on dung, carrion and a variety of organic debris, the Muscidae, Calliphoridae and Sarcophagidae larvae are efficient cleaners of the environment. Once they’re adults, these flies are among the most frequently used in forensic science, since they’re generally the first to arrive on an abandoned body.
- for decades, the vinegar fly, Drosophila melanogaster, has been a model species for genetics studies. In addition, close to 75 percent of the genes responsible for human diseases are similar to those of this little fly! That resemblance offers significant potential for improving the treatment of human diseases, including type 2 diabetes and alcoholism.
Diptera are often perceived as bothersome creatures that transmit illnesses. The fact is, only a few species affect us that way. The great majority of this insect group turns out to be exciting and diversified. You just have to discover them!