Sudden Productivity Collapse Associated with the Triassic-Jurassic Boundary Mass Extinction
- P. Ward, J. Haggart, E. S. Carter, D. Wilbur, H. W. Tipper, T. Evans
- Environmental Science, GeographyScience
- 11 May 2001
Carbon isotope evidence of a pronounced productivity collapse at the boundary, coincident with a sudden extinction among marine plankton, is reported from stratigraphic sections on the Queen Charlotte Islands, British Columbia, Canada.
Pattern of vertebrate extinctions across an event bed at the Permian-Triassic boundary in the Karoo Basin of South Africa
The extinction of vertebrates around the time of the Permian-Triassic boundary has long been regarded as a gradual event occurring over millions of years. Our new field investigations of fluvial…
Pteropods in Southern Ocean ecosystems
Abrupt and Gradual Extinction Among Late Permian Land Vertebrates in the Karoo Basin, South Africa
The vertebrate fossil data show a gradual extinction in the Upper Permian punctuated by an enhanced extinction pulse at the Permians-Triassic boundary interval, particularly among the dicynodont therapsids, coinciding with negative carbon-isotope anomalies.
Rapid warming of the ocean around South Georgia, Southern Ocean, during the 20th century: Forcings, characteristics and implications for lower trophic levels
Vertebrate extinction across Permian–Triassic boundary in Karoo Basin, South Africa
Distinct assemblages of paleosols above and below the Permian–Triassic boundary in the Karoo Basin of South Africa are evidence for reorganization of ecosystems following this greatest of all mass…
South Georgia, antarctica: a productive, cold water, pelagic ecosystem
- A. Atkinson, M. Whitehouse, J. Priddle, G. Cripps, P. Ward, M. Brandon
- Environmental Science
- 6 July 2001
It is suggested that krill and higher predators have a controlling influence on lower trophic levels, both stabilising population sizes and maintaining high rates of energy flow in this food web, through selective grazing and possibly also through nutrient regeneration.
The Galactic Habitable Zone: Galactic Chemical Evolution
Abstract We propose the concept of a “Galactic Habitable Zone” (GHZ). Analogous to the Circumstellar Habitable Zone (CHZ), the GHZ is that region in the Milky Way where an Earth-like planet can…
Rare Earth: Why Complex Life Is Uncommon in the Universe
Contents Preface to the Paperback Edition Preface to the First Edition Introduction: The Astrobiology Revolution and the Rare Earth Hypothesis Dead Zones of the Universe Rare Earth Factors 1 Why Life…
Extensive dissolution of live pteropods in the Southern Ocean
As a result of ocean acidification, aragonite may become undersaturated by 2050 in the upper layers of the Southern Ocean. Analyses of sea snail specimens, extracted live from the Southern Ocean in…