Frei dried fish and preserved them on cardboard – 01/12/2024 – Science

Review of a collection of fish from Brazil deposited in two museums in Portugal revealed that the materials were prepared and described by a Brazilian naturalist, friar José Mariano da Conceição Veloso (1742-1811).

Until then, it was believed that the Portuguese-Brazilian naturalist Alexandre Rodrigues Ferreira (1756-1815) was responsible for the work, dating from the 18th century, since he carried out an expedition to the Brazilian Amazon at the end of that century.

The revelation, described in an article published on the 27th in the scientific magazine Zootaxa, presents an overview of the ichthyofauna (fish fauna) present in the Southeast region — more specifically in the state of Rio de Janeiro — and Brazilian science at the end of the 18th century .

“We thus have a Brazilian representative of science with the same level [de qualidade] and the same height as great European naturalists of the same century, including the identification of several species unknown at the time and which could have been described by him”, said Luis Cerático, first author of the study and researcher at Associação Biopolis and Cibio-InBio ( Research Center for Biodiversity and Genetic Resources) at the University of Porto.

The research also signed Bruna Santos and Thiago Semedo, doctoral students at the University of Porto and Cibio, and Brazilian authors Lucas Garcia and Cristiano Moreira, researchers from the Vertebrates department at the National Museum of UFRJ (Federal University of Rio de Janeiro).

Despite its historical importance, of the more than 700 fish specimens cataloged by Veloso, 87 were recovered — just over 10% — and are described in detail in the study, which also identified and classified the species according to current scientific knowledge.

There is also a record of species that are currently threatened with extinction or that have their geographic distribution restricted due to human activity, such as the grouper (Epinephelus itajara), classified as critically endangered by ICMBio (Chico Mendes Institute of Biodiversity), and the parrotfish (Scarus trispinosus), considered threatened.

The fish were preserved using a method called herborization (“fish herbaria”), a form of dry preservation of the material — today, most scientific collections use preservation in alcohol.

The technique, created by Dutch naturalist Johan Frederik Gronovius (1690-1762), uses the desiccation of fish. The method consists of cutting one side of the animal to remove the skin and entrails, drying the other side to look like a leaf, and, finally, gluing it onto a special type of cardboard for conservation.

It all started as part of Cerático’s doctoral thesis in the history of science. When analyzing some specimens present in Portuguese institutions, more specifically the material found at the Lisbon Academy of Sciences and the Science Museum of the University of Coimbra, the researcher suspected that the material had not been prepared by Alexandre Ferreira.

“There was an idea that everything in Brazil’s zoological or botanical collection at the end of the 18th century in museums in Portugal was Ferreira’s. But he had never preserved the specimens using the herborization technique,” said the author.

The scientist then looked for more information and found a series of letters from Veloso in which he explained the herbarium preservation technique and sent some materials, including fish, to Portugal. The naturalist authored, although published posthumously, a study called “Flora Fluminensis”, in 1825, with several specimens of plants found in the Serra do Mar region, between São Paulo and Rio de Janeiro.

When starting to identify the specimens with the help of colleagues from the UFRJ National Museum, it became clear that there were species found only in Southeastern Brazil, a place that Ferreira had not visited.

The proof, so to speak, occurred when the authors found an unfinished manuscript entitled “Ichthyologia Fluminensis” in the archives of the National Library of Rio de Janeiro, with a description of the fish collected at the time. Cross-referencing the data with materials from the herbarium collection pointed to a direct link. “[A coleção] now it can be better preserved, better studied and even explored, from an educational and scientific extension point of view”, says Cerático.

For Moreira, the discovery of the unfinished manuscript in the National Library brings yet another element to Veloso’s scientific relevance at the time. The naturalist is known as the “father” of Brazilian botany, he says.

“Now we also have an example of its importance for zoological studies, with in-depth knowledge of the anatomy and diversity of fish, presenting detailed information about each one, with a popular name and in old Tupi and suggesting new scientific names for some. It also had data on fishing and geographic distribution. This work was forgotten somewhere and was not used”, said the professor.

This type of scientific study is, today, rare among researchers, who are increasingly guided by the so-called “productivism”, an increasing and faster number of scientific publications. “This shows how, often, the work of scientists is affected by the political and social context of the time,” says Cerático.

Now, the authors intend to work on publishing Veloso’s original manuscript, work that will require time and effort due to the sometimes ineligible condition of the text that was digitized from the National Library collection and the language barrier — the text was written in Latin.

The expectation is that with the publication other researchers will be able to access this information in the future. “He was a naturalist sensu latuwith vast knowledge”, says Moreira. “He saw the variation in the species found here, he didn’t just go after finding those that had already been described for the South American continent by European naturalists.”