A Tatooine world could be habitable despite its inevitably complicated orbit, as long as the planet stays within a particular range of distances from its two host stars, researchers said.
Hawk moths convert nectar to antioxidants. 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.
Based on the video, and the other tests they did on shoelace knots, the team says two things happen when a lace comes untied. First, the impact of the shoe on the ground loosens the knot. With the knot loosened, the whipping of the free ends of the laces — as the leg swings back and forth — makes the laces slip.
As the foot hits the ground and the laces swing repeatedly, the knot loses integrity until, in a matter of seconds, it fails altogether.