Hawk moths convert nectar into antioxidants

Hawk moths have a sweet solution to muscle damage.

Manduca sexta moths dine solely on nectar, but the sugary liquid does more than fuel their bodies. The insects convert some of the sugars into antioxidants that protect the moths’ hardworking muscles, researchers report in the Feb. 17 Science.

When animals expend a lot of energy, like hawk moths do as they rapidly beat their wings to hover at a flower, their bodies produce reactive molecules, which attack muscle and other cells. Humans and other animals eat foods that contain antioxidants that neutralize the harmful molecules. But the moths’ singular food source — nectar — has little to no antioxidants.

So the insects make their own. They send some of the nectar sugars through an alternative metabolic pathway to make antioxidants instead of energy, says study coauthor Eran Levin, an entomologist now at Tel Aviv University. Levin and colleagues say this mechanism may have allowed nectar-loving animals to evolve into powerful, energy-intensive fliers.