The Palaeozoic colonization of the water column and the rise of global nekton

• Published in: Proceedings of the Royal Society. B, Biological sciences Vol. 285; no. 1883; p. 20180883
• Main Authors: Whalen, Christopher D., Briggs, Derek E. G.
• Format: Journal Article
• Language: English
• Published: England The Royal Society 18.07.2018; The Royal Society Publishing
• Edition: Royal Society (Great Britain)
• Subjects: Animals; Aquatic Organisms - physiology; Biodiversity; Biological Evolution; Colonization; Demersal; Devonian; Devonian Nekton Revolution; Ecological monitoring; Invertebrates - physiology; Nekton; Palaeobiology; Palaeoecology; Palaeozoic; Paleontology; Pelagic; Standardization; Swimming; Vertebrates - physiology; Water column; nekton; demersal; Devonian nekton revolution; Palaeozoic; pelagic; palaeoecology
• ISSN: 0962-8452; 1471-2954
• DOI: 10.1098/rspb.2018.0883

The colonization of the water column is among the most important transformations in the evolution of animal life and global ecosystems. The Devonian nekton revolution has been identified as a major macroevolutionary event signifying the rapid occupation of the water column by independent radiations of swimming animals. Using new data, an expanded taxonomic coverage, sample standardization and increased ecological resolution, we analysed patterns of nektonization during the Palaeozoic. We find that nekton and eunekton were well established prior to the Devonian and did not diversify dramatically during any Palaeozoic interval. Relative nektic diversity and occurrences decreased rather than increased during the Devonian. Eunektic diversity and occurrences increased throughout the Palaeozoic, but this rise was protracted and cannot be attributed to any single interval. Our new data indicate that the metazoan colonization of the water column was considerably more complex and gradual than previously understood.