气候变化领域集成服务门户(CCPortal): Low drilling frequency in Norian benthic assemblages from the southern Italian Alps and the role of specialized durophages during the Late Triassic

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DOI	10.1016/j.palaeo.2018.06.034
	Low drilling frequency in Norian benthic assemblages from the southern Italian Alps and the role of specialized durophages during the Late Triassic
	Tackett L.S.; Tintori A.
发表日期	2019
ISSN	0031-0182
起始页码	25
结束页码	34
卷号	513
英文摘要	Drillholes represent one of the clearest lines of evidence for predation of benthic invertebrates in the fossil record and are frequently used as a primary proxy for predation intensity in the fossil record. Drillholes are abundant in the late Cretaceous and Cenozoic, but their occurrence is patchy in older deposits of the Mesozoic. The inconsistent record of drillholes in pre-Cretaceous deposits of Mesozoic age are problematic for interpretations of predation-prey dynamics and adaptive radiations, and the role of taphonomy or diagenesis have not been resolved. Here we present drilling percentages for assemblages of well-preserved shelly benthic invertebrates (mainly comprised of bivalves and rare gastropods) from the upper Norian (Upper Triassic) in northern Italy in order to compare these values with reported drilling percentages from the Carnian San Cassiano Formation, a rare Triassic sedimentary unit that has yielded many drilled fossils. The Norian fossil deposits reported here are comparable to those of the San Cassiano in terms of depositional environment, preservation, and region, and can be reasonably compared to the drilling percentage of fossils from the San Cassiano. The sampled deposits are collected from marly limestone horizons in the Argillite di Riva di Solto in the Southern Italian Alps, deposited in the Lombardian Basin, and which are interbedded with shale units containing well-preserved fish and arthropod fossils, enabling a correlation between paleoecological structure of the shelly benthos and the demersal-pelagic predator diversity. Over four hundred bivalve fossils yielded a drilling percentage of 0.24% (1/406), which is typical for fossil assemblages of this age, but the single occurrence of a drillhole in this study is in marked contrast to the many drilled specimens reported from the San Cassiano Formation deposit in Italy. The drilled specimen (with complete drillhole) was an infaunal bivalve and no incomplete drillholes were observed in other specimens. Thus, drilling percentages for the Triassic are consistently low, but present, suggesting that drilling predation was an ecologically minimal influence to benthic communities and unlikely to have driven the significant ecological changes observed in benthic communities during the Late Triassic. Although drilling predation occurred during the Late Triassic, we present an updated database of specialized durophagous predators (including fishes, sharks, and reptiles) that are likely to have been more ecologically influential on benthic communities during the Norian Stage, fishes in particular. © 2018 Elsevier B.V.
英文关键词	Bivalves; Mesozoic; Predator-prey interactions
语种	英语
scopus关键词	adaptive radiation; arthropod; benthos; bivalve; Cenozoic; Cretaceous; diagenesis; egg predation; fossil assemblage; fossil record; invertebrate; limestone; Mesozoic; Norian; paleoecology; predation; predator; predator-prey interaction; taphonomy; Triassic; Alps; Italy; Arthropoda; Bivalvia; Chondrichthyes; Gastropoda; Invertebrata; Pisces; Reptilia
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151205
作者单位	North Dakota State University, Department of Geosciences, NDSU Dept. 2745, Fargo, ND 58102, United States; Department of Earth Sciences ‘A. Desio’, Università degli Studi di Milano, Milano, Italy
推荐引用方式 GB/T 7714	Tackett L.S.,Tintori A.. Low drilling frequency in Norian benthic assemblages from the southern Italian Alps and the role of specialized durophages during the Late Triassic[J],2019,513.
APA	Tackett L.S.,&Tintori A..(2019).Low drilling frequency in Norian benthic assemblages from the southern Italian Alps and the role of specialized durophages during the Late Triassic.Palaeogeography, Palaeoclimatology, Palaeoecology,513.
MLA	Tackett L.S.,et al."Low drilling frequency in Norian benthic assemblages from the southern Italian Alps and the role of specialized durophages during the Late Triassic".Palaeogeography, Palaeoclimatology, Palaeoecology 513(2019).