Algae use flagella to trot, gallop and move with gaits all their own
A microscopic speck of green algae can trot like a horse. Or gallop. Biophysicist Kirsty Wan compares the gaits of creatures large and small. Moving diagonally opposite limbs, or flagella in this case, in unison — that’s a trot, Wan says. Her lab, at the University of Exeter in England, is working on the conundrum of how single-celled creatures, with no nervous system or brain, coordinate “limbs” to create various gaits. Some of those movements get far trickier than trots and gallops. Her work echoes that of 19th century photographer Eadweard Muybridge, who used a then-novel imaging technique to reveal hoof positions obscured in the blur of a horse galloping. Wan now creates Muybridge moments for microalgae. Using a range of microscopy analytics on what she calls “my private collection of weird algae,” Wan and colleagues have documented microalgae that coordinate from four to 16 flagella. In some four-limbed cells, flagella can move in neighborly pairs, pulling back in a sort of double-vision breaststroke....