High dead-live mismatch in richness of molluscan assemblages from carbonate tidal flats in the Persian (Arabian) Gulf

Non‐indigenous molluscs in the Eastern Mediterranean have distinct traits and cannot replace historic ecosystem functioning

“…abundance-weighting emphasizes the traits of dominant species, reducing the influence of rare taxa, even if they had distinct functional properties; (b) the number of scored trait modalities is limited (23 in this study) and therefore less sensitive to the effects of timeaveraging than taxonomic richness; and (c) the offset occurs in both highly (e.g., station SG30) and minimally time-averaged (e.g., hard substrate stations) death assemblages (Supporting Information Figure S1.2). This reasoning is supported by findings of high fidelity in feeding guild structure even for death assemblages whose taxonomic richness was greatly inflated compared to corresponding living assemblages (García-Ramos et al, 2016).…”

Introductory Chapter: An Introduction to the Stratigraphic Setting of Paleozoic to Miocene Deposits Based on Paleoecology, Facies Analysis, Chemostratigraphy, and Chronostratigraphy - Concepts and Meanings

“…Wide differences of this parameter have been controlled by the early cementation, lateral mixing, strong bioturbation, and low sedimentation rates. The obtained results have suggested that the average times in carbonate tidal flats are higher if compared with the times affecting the subtidal carbonate environments [50].…”

“…Important proxies to carry out these reconstructions include the charcoal and pollens, particularly applied in paleolakes and peats. Some main paleoecological studies have been carried out in the Persian Gulf [49,50]. Abdolmaleki stated as the Permo-Triassic boundary represents one of the most important mass extinctions during the history of the earth, marking for a strong decrease of the living taxa.…”

“…The formation of these facies has also been controlled by the fluctuations in the CaCO 3 saturation level [49]. García-Ramos et al [50] have evaluated the live-dead fidelity of the Mollusk assemblages in soft sediments of the carbonate tidal flats along the coasts of the Persian Gulf. Wide differences of this parameter have been controlled by the early cementation, lateral mixing, strong bioturbation, and low sedimentation rates.…”

The intermingling of benthic macroinvertebrate communities during a period of shifting range: The “East of Nantucket” Atlantic Surfclam Survey and the existence of transient multiple stable states

“…The observation of a species present living, but not in the death assemblage is unusual and normally explained by rarity of occurrence or poor preservability (e.g., Callender & Powell, 2000;Albano, 2014;Martinelli, Madin, & Kosnik, 2016), neither of which is true for Atlantic surfclams in the surveyed region. Long postmortem shell half-lives impose taphonomic inertia into the system which permits the death assemblage to track the history of occupation (Kidwell, 2008;Poirier, Sauriau, Chaumillon, & Bertin, 2010), but which also imposes a time delay between initial colonization and representation in the death assemblage (Olszewski, 2012) and a variable signal of range relinquishment depending on the degree of time averaging (e.g., Perry, 1996;García-Ramos, Albano, Harzhauser, Piller, & Zuschin, 2016). No evidence of range relinquishment exists in this survey despite the wealth of evidence of such farther to the south (Powell et al, 2019), whereas range expansion is documented by multiple evidences including differential size frequencies shallow and deep (large vs. small surfclams), and varying distributions of surfclam shell content.…”