HOOPS AND LOOPS: The first observations of chromosomes in the lampbrush form were made in 1878 using stained sections of axolotl oocyte nuclei. Now, with phase contrast microscopy, scientists can observe the structures moving freely in solution, much as they would inside a developing egg cell. This chromosome, isolated from an axolotl oocyte and imaged in 2003, is almost one millimeter long. (Scale: 50 μm)GARRY MORGAN
In a laboratory in Kiel, Germany, in 1878, cytologist Walther Flemming saw something extraordinary through his microscope. He and a student were studying oocyte development using stained sections of nuclei from an axolotl, a type of salamander. In one of those sections, Flemming could make out long, thin objects with fiber-like protrusions that formed loops, giving the cellular structures a fuzzy appearance.
In 1882, he published his observations of these “merkwürdige und zierliche Anordnungen”—strange and delicate structures. As for what they were, however, Flemming was stumped. “He thought they might be artifacts,” says Garry Morgan, a geneticist at the University of Nottingham in the U.K. “He wasn’t convinced that they were truly cellular structures. . . . He was struggling to recognize what they were—which ...
