Global deep-sea extinctions during the Pleistocene ice ages

Authors
Citation
Bw. Hayward, Global deep-sea extinctions during the Pleistocene ice ages, GEOLOGY, 29(7), 2001, pp. 599-602
Citations number
34
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Earth Sciences
Journal title
GEOLOGY
ISSN journal
0091-7613 → ACNP
Volume
29
Issue
7
Year of publication
2001
Pages
599 - 602
Database
ISI
SICI code
0091-7613(200107)29:7<599:GDEDTP>2.0.ZU;2-F
Abstract
The dark, near-freezing environment of the deep oceans is regarded as one o f the most stable habitats on Earth, and this stability is generally reflec ted in the slow turnover rates (extinctions and appearances) of the organis ms that live there. By far the best fossil record of deep-sea organisms is provided by the shells of benthic foraminifera (Protista), A little-known g lobal extinction of deep-sea benthic foraminifera occurred during the Pleis tocene ice ages. In the southwest Pacific, it caused the disappearance of a t least two families, 15 genera, and 48 species (similar to 15%-25% of the fauna) of dominantly uniserial, elongate foraminifera with distinctive aper tural modifications. These forms progressively died back and became extinct during glacial periods in the late Pliocene to middle Pleistocene (ca, 2.5 -0.6 Ma); most extinctions occurred between 1.0 and 0.6 Ma, at the time of the middle Pleistocene climatic revolution. This first high-resolution stud y of this extinction event indicates that it was far more significant for d eep-sea diversity loss than previously reported (10 species). The middle Pl eistocene extinction was the most dramatic last phase of a worldwide declin e in the abundance of these elongate forms, a phase that began during cooli ng near the Eocene-Oligocene boundary and continued during the middle Mioce ne, Clearly these taxa declined when the world cooled, but the reason is ye t to be resolved.