Beyond functional diversity: The importance of trophic position to understanding functional processes in community evolution

Ecosystem structure—that is the species present, functions they represent, and how those interact—is an important determinant of community stability. This in turn affects ecosystems respond to natural anthropogenic crises, whether or ecological that represent are able persist. Here we use fossil data from museum collections, literature, Paleobiology Database reconstruct trophic networks Tethyan paleocommunities Anisian Carnian (Triassic), Bathonian (Jurassic), Aptian (Cretaceous) stages, compare these a previously reconstructed network modern Jamaican reef community. We generated model food webs consistent with functional structure taxon richnesses communities, compared distributions guild level parameters among assess effect Mesozoic Marine Revolution on ecosystem dynamics. found space communities expanded Aptian, but this pattern was not monotonic. also position for given subject variation depending what other guilds were present stage. The showed lowest degree omnivory by top consumers all networks, dominated longer chains. In contrast, displayed greater short chains attribute presence large predatory guilds, such as sharks bony fish. Interestingly, appeared have higher proportion long chains, case Bathonian. Overall, results indicate highly dependent taxa primary production experienced community, activity consumers. Results study point need better understand when planning restoration activities because may be so altered human restoring its interactions no possible, alternatives must considered restore function. Further work focus elucidating precise roles moderating