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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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Ecology and evolution of Cambrian reefsстатья
- Авторы: Pratt B.R., Spincer B.R., Wood R.A., Zhuravlev A.Yu
- Сборник: The Ecology of the Cambrian Radiation
- Серия: Critical Moments in Paleobiology and Earth History
- Глава в коллективной монографии
- Год издания: 2001
- Издательство: Columbia University Press
- Местоположение издательства: United States
- Первая страница: 254
- Последняя страница: 274
- Аннотация: The history of reef building through the Cambrian records the replacement of pre- dominantly microbial communities by those in which sessile animals participated in construction, so heralding a new reef ecosystem with elaborate trophic webs, complex organism interactions, increased niche partitioning, and high taxonomic diversity. Thus, the domical and branching stromatolites of the Proterozoic (composed mainly of micron-sized crystals precipitated within or trapped upon laminar biofilms) were replaced by highly cavernous, sediment-generating structures constructed by the skeletons of sessile filter feeders, calcified aggregations of coccoid microbes, and mats of cyanobacterial filaments. A new microbial community (Epiphyton-Renalcis) ap- peared in the Nemakit-Daldynian and was joined in the Tommotian by archaeo- cyathan sponges, which colonized both open surfaces and cavities. Other sessile frame builders, such as corals, as well as abundant obligate cryptobionts, demonstrate in- creasing complexity of this ecosystem. Metazoan diversity reached its zenith in the early Botoman. Equally dramatic, however, was the disappearance of this commu- nity toward the end of the Early Cambrian. There followed a protracted interval when reefs were almost entirely microbial. Rigid spiculate demosponges began to occupy late Middle Cambrian reefs, but a level of complexity comparable to that of the Early Cambrian was not achieved again until the Middle Ordovician, when an increase in reef biotic diversity paralleled the radiation of the shelly benthos.
- Добавил в систему: Журавлев Андрей Юрьевич