Historiographical accounts typically place the formulation of the first embryological theory of the evolutionary origin of vertebrates after the publication of Darwin’s On the Origin of Species. However, the French naturalist Étienne Geoffroy Saint-Hilaire developed an embryological evolutionary model in the 1820s that followed the Lamarckian theory. Geoffroy was the first to establish a direct embryological relationship between vertebrates and invertebrates. This idea was not forgotten, and the embryologists Anton Dohrn and Carl Semper subsequently updated it in their annelid theory (...) as part of a debate about the origin of vertebrates that occurred during the latter part of the nineteenth century. This paper reviews the traditional historiography, analyzing and integrating Geoffroy’s model into the current body of ideas. (shrink)

Biological sciences have strived to adopt the conceptual framework of physics and have become increasingly quantitatively oriented, aiming to refute the assertion that biology appears unquantifiable, unpredictable, and messy. But despite all effort, biology is characterized by a paucity of quantitative statements with universal applications. Nonetheless, many biological disciplines—most notably molecular biology—have experienced an ascendancy over the last 50 years. The underlying core concepts and ideas permeate and inform many neighboring disciplines. This surprising success is probably not so much attributable (...) to mathematical and statistical approaches in molecular biology, but rather to the preponderance of qualitative approaches, especially visualization. Visualizations can be afforded by quantitative research, but usually they rely on both, quantitative and qualitative research. I claim the following three features to be responsible for the unceasing zeal for using visualizations: visual representations facilitate reasoning, images can be cognitively processed in a “fast” manner, and abstractions of visual representations prompt conceptual advances. In summary, visualizations have largely contributed to the success of molecular biology by conveying its concepts to other disciplines, and at the same time, eclipsing mere quantitative approaches. However, visualizations also bear the risk of misinterpretation when traversing neighboring disciplines and even more so when pervading nonscientific domains. (shrink)