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The word “antibacterial” generally refers to some sort of chemical substance that kills bacteria. Like antibacterial soap. Cicadas, which don’t always have access to antibacterial soap (the insect market is woefully under served by household cleaning products), have evolved a way to kill bacteria that’s built right into the structure of their wings.

Under an electron microscope, cicada wings are covered with forests of tiny nanopillars, smaller than bacteria. These are pillars, not spikes, with blunt tops as opposed pointy ones. When a bacterium comes in contact with the wing surface, it sticks to these nanopillars, which hold it up in some places but not in others. The bacterial membrane then sags into the spaces between the pillars, and if it sags enough, it’ll rupture, killing the bacterium.

Think about it like one of those inflatable swimming pools: if you fill it with SpaghettiOs and then try to lift it from the sides, the unsupported bottom will eventually tear open and you know what happens next.

This discovery is exciting because it should eventually be possible to replicate the cicada wing structure with synthetic materials and create a mass-producible antibacterial surface. Then we can stick that everywhere, like on public transportation and in bathrooms and Denny’s restaurants — that sort of thing. If we wallpaper these places with cicada-wing nanomaterials that kill bacteria on contact, we won’t have to waste time and money and the goodwill of Mother Earth with chemical cleaning agents, and surfaces will stay bacteria-free permanently.

Three years ago, scientists discovered electric currents running through the seabed — but they had no idea what was causing them. But now, researchers from Denmark and the United States believe they have the answer: bacteria that function as living electrical cables. In a remarkable case of biological engineering, scientists have confirmed that each tiny section of the bacteria contains a bundle of insulated wires that leads an electric current from one end to the other.

The discovery could lead to an entirely new class of organic electronics — including devices that could be implanted in the human body.

According to Nils Risgaard-Petersen, Christian Pfeffer, and their colleagues at Aarhus University, they started to suspect that something was up when they noticed the appearance of a previously unknown type of long, multi-cellular bacteria. These bacteria were always present when electric currents were around. Moreover, they could disrupt the currents when they pulled a thin wire through the seabed — a possible indication of broken connections.

Looking at it more closely, they noticed that the bacteria, which is a hundred times thinner than a human hair, contained nanoscale strings that were enclosed by a membrane. They concluded that the entire organism functions as a virtual electric cable — insulating wires and all. And indeed, the researchers note that the structure is very similar to the electric cables that we use on a daily basis.

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