Between the end of the 19th century and the beginning of the 20th, Charles Darwin’s theory of evolution was frequently discussed and in particular the causes of evolution were deeply debated. The English naturalist Julian Huxley called this phase “eclipse of Darwinism” to indicate the fact that the idea of evolution of living beings was widely accepted in scientific societies, but not all naturalists accepted that natural selection and random changes (which we now attribute to mutations) were the main causes of this process.
Numerous Italian naturalists participated to this debate and it is interesting to read today their contributions not only from a historical point of view, but also from an epistemological perspective, since this debate is still very useful to understand how a scientific theory may evolve through the debate originating within the international scientific community.
In order to reconstruct this interesting historical phase, the project “The causes of evolution: Daniele Rosa and the contribution of the naturalists of Modena in the origin of modern evolutionary biology” has been carried out. The project, based on the collaboration between the University of Modena and Reggio Emilia and the National Academy of Sciences, Letters and Arts of Modena, allowed the revisiting of the work of the zoologist and naturalist Daniele Rosa (1857-1944) and supported the suggestion that his work should be, with full merit, included in the active discussion about the role of natural selection that characterized the eclipse of Darwinism. In order to achieve this result, the complete digitization of Rosa’s scientific publications (including scientific articles and books) was carried out.
Furthermore, the National Academy of Sciences, Letters and Arts of Modena completely digitized the Rosa’s correspondence (which remained unpublished until today), making possible not only a better understanding of the work of Daniele Rosa, but also allowing an unprecedented overview of the numerous interactions that Rosa has been able to build and maintain with his students and with numerous and influential naturalists of his time.
The correspondence, freely donated by Professor Jobst Wendt (University of Tübingen) to the National Academy of Sciences, Letters and Arts of Modena in 2018, was indexed and catalogued by the Librarians of the National Academy of Sciences, Letters and Arts of Modena, while its digitization was handled by the photographer Vincenzo Negro. The correspondence consists of nearly nine hundred letters and postcards sent in the years 1857-1944 and it includes nearly three hundred correspondents.
The project “The causes of evolution” also included the survey of the collections of the Museum of Zoology and Comparative Anatomy of the University of Modena and Reggio Emilia in order to verify the presence of the samples that Daniele Rosa reported as deposited in the museum at the beginning of the Nineteenth century, but that are still not catalogued. This survey allowed the identification of 19 samples of oligochaetes deposited in the museum and studied by Rosa. The most important specimen is related to the annelid Allolobophora cuginii, described for the first time by Rosa in 1905, since it represents the holotype for this species.
The oligochaete samples of Rosa have been removed from the museum exhibition since several decades and this is not surprising considering that not necessarily all samples must be always present in the museum exhibition. However, Rosa’s “rediscovered” samples remind us that each specimen conserved in a natural history museum possesses a sort of stratigraphy, an overlapping of meanings that can be narrated and handed down from time to time. Very often uniquely the physical destruction of a specimen is perceived as a damage for a museum, but the loss of the history of samples makes them mute, unable to communicate the history they carry with them. To give full value to the museum collections, we must remind the importance of archives preserving the history of those samples, as well as the importance they have played in the history of natural sciences and for museum scholars.
Interestingly, the project “The causes of evolution” made possible to bring together, albeit only digitally, the museum’s samples with the scientific publications that have been part of the library of the Museum of Zoology for many decades and that describe the origin of each specimen.
“No human satisfaction can certainly be equal that of who, reached an old age, going through the past years with his mind, feels with serene evaluation the work done, that he has lived not in vain and that his work is destined to leave deep and lasting traces in the history of the scientific thought. This feeling, the unique great reward in the fate reserved for few selected scientists, was present in the soul of Daniele Rosa when, more than eighty and almost blind, he spent hours recalling the years spent for his studies and for meditating on the scientific problems that occupied his life”. With these words, the zoologist Giuseppe Colosi remembered Rosa celebrating his work some decades after his death.
Unfortunately, with the exception of some citations, Daniele Rosa’s work has been forgotten by evolutionists losing consciousness of Rosa’ intuitions and conclusions that are actually still present in the current evolutionary debate. Fully embracing the admiration of Colosi, the University of Modena and Reggio Emilia and the National Academy of Sciences, Letters and Arts of Modena make these precious texts and materials available today.