#1415: a vole clock is a way of measuring really large amounts of time. the vole evolved so rapidly over the past few million years, and we have such a good idea of precisely how it evolved, that finding teeth of a vole at an archaeological site is enough to accurately date the site to extents that carbon-14 can't. it dated Boxgrove Man, a Sussex residency site and the first record of humans in England that long ago, to 500,000 years give or take only 25,000. however, it's not perfect: because evolution isn't linear, some argue that statistically speaking it's not any better than other methods of biochronology and palaeontology and gives a lot of false precision.