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Understanding the roles of habitat filtering, dispersal limitations and biotic interactions in shaping the organization of animal communities is a central research goal in ecology. Attempts to extend these approaches into deep time have the potential to illuminate the role of these processes over key intervals in evolutionary history. The Ediacaran marks one such interval, recording the first macroscopic benthic communities and a stepwise intensification in animal ecosystem engineering. Here, we use taxonomic co-occurrence analysis to evaluate how community structure shifted through the late Ediacaran and the role of different community assembly processes in driving these changes. We find that community structure shifted significantly throughout the Ediacaran, with the most dramatic shift occurring at the White Sea–Nama boundary (approx. 550 Ma) characterized by a split between older, more enigmatic taxonomic groups (the ‘Ediacara-type’ fauna) and more recognizable (‘Cambrian-type’) metazoans. While ecosystem engineering via bioturbation is implicated in this shift, dispersal limitations also played apart in separating biota types. We hypothesize that bioturbation acted as a local habitat filter in the late Ediacaran, selecting against genera adapted to microbial mat ecosystems. Ecosystem engineering regime shifts in the Ediacaran may thus have had a large impact on the development of subsequent metazoan communities.
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How to engineer a habitable planet: the rise of marine ecosystem engineers through the Phanerozoic
Abstract Ecosystem engineers are organisms that modify their physical habitats in a way that alters resource availability and the structure of the communities they live in. The evolution of ecosystem engineers over the course of Earth history has thus been suggested to have been a driver of macroevolutionary and macroecological changes that are observed in the fossil record. However, the rise to dominance of ecosystem engineers has not been thoroughly reconstructed. Here, we investigate the history of bioturbation and reef‐building (two of the most important marine ecosystem engineering behaviours today) over the Phanerozoic. Using fossil occurrences from the Paleobiology Database, we reconstruct how common communities influenced by ecosystem engineers were in the oceans, how dominant ecosystem engineers were within their own communities, and the taxonomic and ecological composition of bioturbators and reef‐builders. We find that bioturbation has become an increasingly common ecosystem engineering behaviour over the Phanerozoic, while reef‐building ecosystem engineers have not become more dominant since their Devonian apex. We also identify unique bioturbation and reef‐building regimes that are characterized by different ecosystem engineering taxonomic groups, ecological modes, and dominance, suggesting that the nature of ecosystem engineering has at times rapidly shifted over the course of the Phanerozoic. These reconstructions will serve as important data for understanding how ecosystem engineers have driven changes in biodiversity and ecosystem structure over the course of Earth history.
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- Award ID(s):
- 2051255
- PAR ID:
- 10549761
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Palaeontology
- Volume:
- 67
- Issue:
- 5
- ISSN:
- 0031-0239
- Subject(s) / Keyword(s):
- Evolution ecosystem engineering reefs bioturbation
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1111/pala.12726
