One of the most common natural disasters, but also one of the most commonly forgotten, is wildfires. These take place in many different countries all over the world, particularly during the summer months, and can be caused by a range of different things. Some of the things that can start the wildfires can be totally natural, while others can be manmade, but the speed at which they spread is entirely down to nature. The two natural causes of wildfires are the sun’s heat and lightning strikes, while they can also be caused by campfires, smoking, fireworks and many other things. The reasons that they spread so quickly are prolonged hot, dry weather, where the vegetation dries out, which is why they often take place in woodland.
Many bacteria and other microorganisms have obvious adaptations to overcome low Reynolds numbers; they row thousands of hairlike projections called cilia or corkscrew their way through fluid with powerful spinning tails known as flagella. Other bacteria and their kin have puzzled researchers by swimming just fine without such external accoutrements. In recent years scientists have revealed how some of these more mysterious microbes get around: a few rely on complex internal motors that ripple the cell surface; one bacterium can turn mucus in the human stomach into a much thinner fluid; and another microbe has, shall we say, a rather kinky way of moving. I describe such adaptations in more detail in a feature article in the August issue of Scientific American —the culmination of my slip-‘n-slide journey into the wonderfully weird world of microbes in molasses.