Patterns of evolution before extinction of Triassic conodonts
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چکیده
منابع مشابه
Phanerozoic survivors: Actinopterygian evolution through the Permo‐Triassic and Triassic‐Jurassic mass extinction events
Actinopterygians (ray-finned fishes) successfully passed through four of the big five mass extinction events of the Phanerozoic, but the effects of these crises on the group are poorly understood. Many researchers have assumed that the Permo-Triassic mass extinction (PTME) and end-Triassic extinction (ETE) had little impact on actinopterygians, despite devastating many other groups. Here, two m...
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15 صفحه اولanalyzing patterns of classroom interaction in efl classrooms in iran
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Selective extinction among end-Triassic European bivalves
Ongoing controversies surrounding the end-Triassic extinction highlight the need for identifying a causal mechanism leading to extinction. Bivalve data from Lombardia (Italy), Northern Calcareous Alps (Austria and Germany), and northwest Europe (England and Wales) provide the biologic signal of selective extinction to compare two competing extinction hypotheses: (1) sea-level change and associa...
متن کاملEvidence from ammonoids and conodonts for multiple Early Triassic mass extinctions.
Ammonoids and conodonts, being characterized by exceptionally high background rates of origination and extinction, were vulnerable to global environmental crises, which characteristically intensified background rates of extinction. Thus, it is not surprising that these taxa suffered conspicuous mass extinctions at the times of three negative Early Triassic global carbon isotopic excursions that...
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ژورنال
عنوان ژورنال: The Paleontological Society Special Publications
سال: 1992
ISSN: 2475-2622,2475-2681
DOI: 10.1017/s2475262200006894