Post-Paleozoic crinoid radiation in response to benthic predation preceded the Mesozoic marine revolution.
It has been argued that increases in predation over geological time should result in increases in defensive adaptations in prey taxa. Recent in situ and laboratory observations indicate that cidaroid sea urchins feed on live stalked crinoids, leaving distinct bite marks on their skeletal elements. Similar bite marks on fossil crinoids from Poland strongly suggest that these animals have been subject to echinoid predation since the Triassic. Following their near-demise during the end-Permian extinction, crinoids underwent a major evolutionary radiation during the Middle-Late Triassic that produced distinct morphological and behavioral novelties, particularly motile taxa that contrasted strongly with the predominantly sessile Paleozoic crinoid faunas. We suggest that the appearance and subsequent evolutionary success of motile crinoids were related to benthic predation by post-Paleozoic echinoids with their stronger and more active feeding apparatus and that, in the case of crinoids, the predation-driven Mesozoic marine revolution started earlier than in other groups, perhaps soon after the end-Permian extinction.
Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48105, USA. tomaszb@umich.edu
Tomasz K
TK
Baumiller
Mariusz A
MA
Salamon
Przemyslaw
P
Gorzelak
Rich
R
Mooi
Charles G
CG
Messing
Forest J
FJ
Gahn
D000818:Animals; D005075:Biological Evolution; D004447:Echinodermata / Q000033:anatomy & histology / Q000145:classification* / Q000502:physiology; D017753:Ecosystem; D020387:Food Chain; D005580:Fossils; D049690:History, Ancient; D008386:Marine Biology