Search

Following the 'rediscovery' of Mendel's work around 1900 the study of genetics grew rapidly and multiple new inheritance theories quickly emerged such as Hugo de Vries' "Mutation Theory" (1901) and the "Boveri-Sutton Chromosome Theory" (1902). Mendel's work also caught the attention of the German geneticist Valentin Haecker, yet he was generally dissatisfied the simplicity of Mendelian genetics as he believed that inheritance and the expression of various characteristics appeared to be much more complex than the proposed "on-off hypotheses". Haecker's primary objection was that Mendelian-based theories still failed to bridge the gap between hereditary units and phenotypic traits. Haecker thus set out to bridge this gap in his research program, which he called Phanogenetik ("phenogenetics"). He outlined his work in a special study "Entwicklungsgeschichtliche Eigenschaftsanalyse (Phanogenetik)" in 1918. 2018 thus marks the 100th anniversary of Haecker's seminal publication, which was devoted to the analysis of the phenotype and highlighted the true complexity of heredity. This article takes a specific look at Haecker and his work, while also illustrating how this often forgotten scientist influenced the field of genetics and other scientists.

This essay will analyse early attempts to base anthropology on the theoretical model provided by the emerging synthetic Darwinism of the 1940s. In the first section we will investigate the historical context of the publication of one of the central documents of synthetic Darwinism in Germany: Gerhard Heberer's Die Evolution der Organismen (1943). Anthropology was covered extensively in this book. The second section will give an impression of the live and work of the five anthropologists represented in Heberer's book: Christian von Krogh, Wilhelm Gieseler, Otto Reche, Hans Weinert, and Gerhard Heberer. The third part of our paper will clarify whether these anthropologists shared a common theoretical outlook with the founders of synthetic Darwinism, and to what degree they were committed to the racial ideas of the Third Reich.

After a short description of the history of comparative anatomy and morphology in the German-speaking area this article presents three important zoologists and morphologists and their individual scientific concepts. Alexej N. Sewertzoff, Victor Franz and Hans Böker belong to the most important morphologists in the twentieth century. In this century, morphology went through several rises and declines in Germany: the first decline took place after the death of the anatomist Max Fürbringer in 1920, the second during and after the Third Reich. In Germany at the beginning of the 1930s and 1950s different parts of an evolutionary morphology concept were recycled with important ideas by Sewertzoff and through scientific activities of Dietrich Starc's morphology school in Frankfurt am Main.

Evolutionary theory has been likened to a "universal acid" (Dennett 1995) that eats its way into more and more areas of science. Recently, developmental biology has been infused by evolutionary concepts and perspectives, and a new field of research--evolutionary developmental biology--has been created and is often called EvoDevo for short. However, this is not the first attempt to make a synthesis between these two areas of biology. In contrast, beginning right after the publication of Darwin's Origin in 1859, Ernst Haeckel formulated his biogenetic law in 1872, famously stating that ontogeny recapitulates phylogeny. Haeckel was in his turn influenced by pre-Darwinian thinkers such as Karl Ernst von Baer, who had noted that earlier developmental stages show similarities not seen in the adults. In this review, written for an audience of non-specialists, we first give an overview of the history of EvoDevo, especially the tradition emanating from Haeckel and other comparative embryologists and morphologists, which has often been neglected in discussions about the history of EvoDevo and evolutionary biology. Here we emphasize contributions from Russian and German scientists to compensate for the Anglo-American bias in the literature. In Germany, the direct influence of Ernst Haeckel was felt particularly in Jena, where he spent his entire career as a professor, and we give an overview of the "Jena school" of evolutionary morphology, with protagonists such as Oscar Hertwig, Ludwig Plate, and Victor Franz, who all developed ideas that we would nowadays think of as belonging to EvoDevo. Franz ideas about "biometabolic modi" are similar to those of a Russian comparative morphologist that visited Jena repeatedly, A. N. Sewertzoff, who made important contributions to what we now call heterochrony research--heterochrony meaning changes in the relative timing of developmental events. His student I. I. Schmalhausen became an important contributor to the synthetic theory of evolution in Russia and is only partly known outside of the Russian-reading world because only one of his many books was translated into English early on. He made many important contributions to evolutionary theory and we point out the important parallels between Schmalhausen's ideas (stabilizing selection, autonomization) and C. H. Waddington's (canalization, genetic assimilation). This is one of the many parallels that have contributed to an increased appreciation of the internationality of progress in evolutionary thinking in the first half of the twentieth century. A direct link between German and Russian evolutionary biology is provided by N. V. Timoféeff-Ressovsky, whose work on, e.g., fly genetics in Berlin is a crucial part of the history of evo-devo. To emphasize the international nature of heterochrony research as predecessor to the modern era of EvoDevo, we include Sir G. R. de Beer's work in the UK. This historical part is followed by a short review of the discovery and importance of homeobox genes and of some of the major concepts that form the core of modern EvoDevo, such as modularity, constraints, and evolutionary novelties. Major trends in contemporary EvoDevo are then outlined, such as increased use of genomics and molecular genetics, computational and bioinformatics approaches, ecological developmental biology (eco-devo), and phylogenetically informed comparative embryology. Based on our survey, we end the review with an outlook on future trends and important issues in EvoDevo.