One of the main “databases”, on which palaeontologists carry on their studies, is constituted by palaeontological collections. These collections are the final result of fieldwork and surveys, sampling activities, preparation and curatorial processes, and analyses. However, the content of a palaeontological collection can also be strongly biased, leading researchers to post-collection skewed results. Post-collection biases (e.g., breakage, loss of fragments, etc.) are directly linked to human activities, occurring during excavation, transport, preparation, and storage. Here, we present the case of the vertebrate remains from the Brazilian lower Carnian Santacruzodon Assemblage Zone (Santa Cruz Sequence, Santa Maria Supersequence, Paraná Basin). The studied specimens came from the Schoenstatt Sanctuary fossil site, a key outcrop for both the sequence and Santacruzodon AZ. We evaluated vertebrate remains from three Brazilian scientific collections, compiled through more than 25 years of fieldwork. The specimens housed in the three collections present high degrees of post-collection fragmentation, as well as significant differences in the bone elements present, when comparing cranial vs. post-cranial elements. Moreover, some differences in curatorial attitude have also been noticed, especially in restoration choices, leading to “discrimination” in post-collection fossil quality and highlighting the existence of the “craniocentrism” problem.

Key words: Anthropogenic bias, anthropogenic breakage, Schoenstatt Sanctuary site, Santacruzodon AZ, Carnian, Triassic, South America.

Francesco Battista [francesco.battista87@gmail.com; ORCID: https://orcid.org/0000-0002-6154-1906], Fernando Erthal [fernando.erthal@ufrgs.br; ORCID: https://orcid.org/0000-0001-8036-192X], and Cesar L. Schultz [cesar. schultz@ufrgs.br; ORCID: https://orcid.org/0000-0001-7121-0409], Programa de Pós-Graduação em Geociências, Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves 9500, Agronomia, 91501-970 Porto Alegre, Rio Grande do Sul, Brazil Ana Maria Ribeiro [ana-ribeiro@sema.rs.gov.br; ORCID: https://orcid.org/0000-0003-4167-8558], Museu de Ciências Naturais do Rio Grande do Sul, Secretária Estadual do Meio Ambiente e Infraestrutura, Rua Dr. Salvador França, 1427, Jardim Botânico, 90690-000 Porto Alegre, Rio Grande do Sul, Brazil; and Programa de Pós-Graduação em Geociências, Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Avenida Bento Gonçalves 9500, Agronomia, 91501-970 Porto Alegre, Rio Grande do Sul, Brazil.