Behaviors mapped by new geographies: Ichnonetwork analysis of the Val Dolce Formation (lower Permian; Italy-Austria)

摘要: The Pramollo Basin (Italy-Austria) is one of the richest body and trace fossil sites Alps, exhibits a well-preserved Permian–Carboniferous fluvio-deltaic to marginal-marine sedimentary succession. Despite exceptionally abundant ichnological heritage, fossils are not well studied, particularly those Permian units. This study focuses on ichnofauna Val Dolce Formation (Permian; partly Asselian Sakmarian), with goal documenting its heritage reconstructing paleoenvironment. These research questions addressed by applying network theory, an emerging field complexity science that web-like systems made interconnected entities. An system can be seen as set interlinked ichnotaxa, topology which depends organism-environment interactions. In addition, traditional paleontological sedimentological observations used reconstruct following ichnotaxa documented from Formation: Archaeonassa isp., Curvolithus simplex , Cylindrichnus Helminthoidichnites tenuis Nereites missouriensis Planolites Phymatoderma Pramollichnus pastae Psammichnites plummeri Taenidium Zoophycos isp. Network analysis indicates structured, organized in environment-driven ichnoassociations: - (proximal delta front), (prodelta dysoxic porewaters), (distal front–proximal prodelta), (prodelta). Furthermore, front–prodelta gradient accompanied increasing bioturbation intensity diversity, reflecting decreasing major environmental stressors (hydrodynamics, freshwater input, turbidity). Centrality measures allow topological position traces discerned within studied system, detecting paleoenvironmental resolution individual ichnotaxa. As intersections sets described networks, ichnoassociations considered occupying intersecting behavioral niches. analogy concept Hutchinsonian niche, ichnotaxon’s niche exists multidimensional abstract space defined parameters, expressed spatial variables paleolandscape. Consequently, just association patterns, but represent spatial, environmental, approach allows reconstitution relationships between geographical ranges ichnoassociations, providing information physical arrangement different subenvironments, is, structure