Walther Flemming: life path and scientific legacy

Abstract

The main stages of Walther Flemming life and activity are considered in the article. Walther Flemming (21.04.1843–4.08.1905) is German biologist, anatomist, one of the most famous histologists of the 19th century and the founder of cytogenetics. He studied medicine at four famous universities of the German Empire – in Göttingen, Tübingen, Berlin and Rostock. After defending his thesis, in 1868 he started teaching anatomy and histology at Würzburg, Amsterdam and Rostock universities, Germany and Charles Ferdinand University, the Czech Republic. During the last 25 years of his life, he was a professor of anatomy at the Christian Albrecht University in Kiel, Germany and headed one of its departments – the anatomical institute. At the beginning of W. Flemming scientific activity, his research mostly concerned histology and anatomy, as well as the development of histological methods and fixation of microscopic specimens. However, the main works of the scientist are devoted to study cell division process and the chromosomes distribution in daughter nuclei. He firstly introduced the concept of “mitosis”, which he studied on stained microscopic preparations, using salamander epithelial cells as a source of biological material. W. Flemming described the processes in the nucleus, distinguished “progressive” and “regressive” phases of cell division. He demonstrated that the cells contain areas that absorb basophilic dyes. These areas were later called chromatin; other structures remained unstained under such conditions and were therefore called achromatin. W. Flemming studied the structure and functions of the spindle during cell division, and he also studied the polar structure, which he called centriole. The scientist found that indirect division usually occurs not only in vertebrates, but also in invertebrates and protists. He established that two successive, morphologically distinct divisions of nuclear occur during spermatogenesis, resulting in the division of chromatin into two daughter cells. Thus, W. Flemming’s research contributed to the development of cell biology and its branches.