Insects can be found in every environment on Earth and play critical roles in the planet’s ecosystems. Insects pollinate more than 80% of plants, including those that we eat and those that provide food and habitat for other species. Without insects, we wouldn’t have the rich biodiversity that supports life on earth today.
But the world is experiencing a decline in overall insect populations as well as a collapse in insect diversity. According to researchers from the University of Melbourne in Australia, Beijing Forestry University in China, and the University of California – Davis, air pollution particles may be the cause of the dramatic decline. They found that an insect’s ability to find food and a mate is reduced when their antennae are contaminated by particulate matter.
In the study, which was recently published in the journal Nature Communications, the research team exposed houseflies to varying levels of air pollution for just 12 hours and then placed the flies in a Y-shaped tube ‘maze’. Uncontaminated flies typically chose the arm of the Y-maze leading to a smell of food or sex pheromones, while contaminated flies selected an arm at random, with 50:50 probability.
Using a scanning electron microscope, the researchers also found that as air pollution increases, more particulate material collects on the sensitive antennae of houseflies.
Insect antennae have olfactory receptors that detect odor molecules emanating from a food source, a potential mate, or a good place to lay eggs. If an insect’s antennae are covered in particulate matter, a physical barrier is created between the smell receptors and air-borne odor molecules.
Air pollution poses a significant threat to insect populations around the world.
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Air pollution particles may be cause of dramatic drop in global insect numbers
Photo, posted June 13, 2008, courtesy of Allen Watkin via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio