Slate here ponders the consistency of the upper limits of the human lifespan: "Last month, a 114-year-old former schoolteacher from Georgia named Besse Cooper became the world's oldest living person. Her predecessor, Brazil's Maria Gomes Valentim, was 114 when she died. So was the oldest living person before her, and the one before her. In fact, eight of the last nine 'world's oldest' titleholders were 114 when they achieved the distinction. Here's the morbid part: All but two were still 114 when they passed it on. Those two? They died at 115. The celebration surrounding Cooper when she assumed the title, then, might as well have been accompanied by condolences. If historical trends hold, she will likely be dead within a year. It's no surprise that it's hard to stay the 'world's oldest' for very long. These people are, after all, really old. What's surprising is just how consistent the numbers have been." Based on the work of the Supercentenarian Research Foundation we might suspect a single class of age-limiting process - something different from the collection of common issues and biological system failures that kill most people across their 70s, 80s, and 90s. Autopsies of supercentenarians revealed that they die from a form of amyloidosis, something that you will only rarely see in younger old people. Fortunately this is very amenable to foreseeable treatments - so as rejuvenation biotechnology advances, we need not worry too greatly about this apparently limiting process.