Deep-Diving Fly Larvae in Lake Malawi Defy Pressure Explanation for Absence of Ocean Insects
Chaoborus edulis, a species of lake fly unique to Lake Malawi, has the ability to dive to depths exceeding 650 feet, occasionally reaching as far as 850 feet, which contradicts the belief that insect respiratory systems fail under high oceanic pressure. A study published in Science on July 23 reveals that their air sacs, which are strengthened by resilin and a rigid cuticle, facilitate buoyancy regulation. Researchers from the University of British Columbia observed that larvae descend to the hypolimnion at a rate of 25 feet per hour and ascend at 65 feet per hour to evade fish predators. The pupae of C. edulis endured pressures comparable to 1,519 feet of water. Co-author Evan McKenzie indicates that resilin may inspire innovative materials, while Philip Matthews highlights that crustaceans occupy these ecological niches.
Key facts
- Chaoborus edulis larvae dive more than 650 feet in Lake Malawi, with some reaching 850 feet.
- Study published in Science on July 23 challenges the idea that pressure prevents insects from living in the ocean.
- The larvae use air sacs containing resilin, an elastic protein, to withstand high pressure.
- Researchers deployed underwater sonar to track the insects' daily vertical migrations.
- Larvae sink in the morning to avoid fish and rise at night to feed on zooplankton.
- C. edulis pupae can withstand pressures equivalent to 1,519 feet of water depth.
- The strength of air sacs correlates with the maximum depth of each species' environment.
- The findings may inspire new materials such as artificial muscles or pH-activated valves.
Entities
Artists
- Philip Matthews
- Evan McKenzie
- Natasha Mhatre
- Flora Lichtman
- Mary Randolph
- Margherita Bassi
Institutions
- University of British Columbia
- University of Western Ontario
- Science
- Science Friday
- Scientific American
- Popular Science
Locations
- Lake Malawi
- Malawi
- East Africa
- Canada