Fluffy flies specialize in swimming in the water

One possesses "external lungs" that can help them grow vigorously in places where almost no living species can live.

Lake Mono , California, USA, is home to Ephydra hians , according to National Geographic. The researchers found that the diver could tolerate high alkalinity in lake water to dive to feed and lay eggs. Their hairs create a surrounding air bubble that acts as an external lung.

Research on hairy flies is the work of Floris van Breugel, a member of the National Geographic Society for Discovery and Research and postdoctoral research students at the University of Washington. The Geographic Association sponsored van Breugel to study the flies living in Lake Mono.

Ephydra hians are hairy and live under high alkaline water in Lake Mono, California.(Photo: Floris van Breugel).

The number of flies living in the lake is impressive. They are so dense that the density is about 2,000 flies on an area the size of a postcard. Van Breugel estimates that in the summer peak, there are about 100 million flies around Mono Lake."You will see them crawling under the water inside small bubbles," van Breugel said.

Van Breugel and his colleagues wanted to find out how the alkaline flies at Lake Mono dive underwater, where the salt content was three times higher and more alkaline than the ocean, without getting wet. The only organism ever recorded to live year-round in such an environment is the photosynthetic algae and a small species of shrimp. Research by van Breugel group was published on November 20 in the journal of the US National Academy of Sciences.

Scientists build a sensor that can measure small forces. They also put alkaline flies in different environments to conduct experiments. The team was surprised to find that the thicker the lake, the easier it was for flies to drown. They discovered the cause due to sodium carbonate . Sodium carbonate makes alkaline flies difficult to maintain their bodies dry because water easily penetrates into the space between their hairs.

Adaptation and evolution through lifetimes help alkaline flies have 36% more hairs than the average of the other flies that the team used to experiment. Fly feathers are wrapped in a special wax, allowing them to remain dry.

According to scientists, this hair change has a great impact on ecosystems because Lake Mono is the stop of more than 2 million migratory birds each year. About 85% of California gulls nest on islands in Lake Mono. Van Breugel's discovery is an example of how small evolution such as the number of feathers of a fly can still affect ecosystems.