In 1851, the Swiss anatomist Hermann Meyer dissected the eyes of a newborn dog and noticed that the cells at the center of the lens lacked nuclei. This observation and subsequent similar findings were little more than a curiosity for nearly half a century. Between 1897 and 1899, however, the Austrian anatomist Carl Rabl published a series of seminal papers in which he described the embryonic development and adult morphology of the lens in great detail. Rabl, then working at the German Karl-Ferdinands University in Prague, systematically analyzed the lenses of dozens of vertebrate species, including kiwi birds, chameleons, martens, alligators, chamois, bats, rays, and axolotls, among the more exotic.
In his work, he demonstrated that the nuclei begin to degrade at a precise point in lens cell differentiation. Nuclei first round up and shrink, the chromatin then condenses into large clumps, and, finally, all the nuclei in the center ...
