Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician
Abstract The high rate of species extinction in recent decades is seen by many ecologists as heralding an extinction of catastrophic magnitude in the near future. The ecological consequences of such a biodiversity crisis are hard to predict, but some indication of likely effects can be gained from t...
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Online Access: | http://dx.doi.org/10.1002/gj.880 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fgj.880 https://onlinelibrary.wiley.com/doi/pdf/10.1002/gj.880 |
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crwiley:10.1002/gj.880 2024-09-30T14:36:28+00:00 Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician Brenchley, P. J. Marshall, J. D. Underwood, C. J. 2001 http://dx.doi.org/10.1002/gj.880 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fgj.880 https://onlinelibrary.wiley.com/doi/pdf/10.1002/gj.880 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Geological Journal volume 36, issue 3-4, page 329-340 ISSN 0072-1050 1099-1034 journal-article 2001 crwiley https://doi.org/10.1002/gj.880 2024-09-11T04:11:20Z Abstract The high rate of species extinction in recent decades is seen by many ecologists as heralding an extinction of catastrophic magnitude in the near future. The ecological consequences of such a biodiversity crisis are hard to predict, but some indication of likely effects can be gained from the knowledge of mass extinctions in the past. The Late Ordovician extinction was one of the five great extinctions in the geological record. It occurred in two phases about 0.5–1million years (Ma) apart and resulted from climatic and related environmental changes associated with the rapid growth and decay of the large Gondwanan ice cap. Overall, an estimated 86% of species became extinct, 61% of genera and 12–24% of families, but few or no orders or higher taxa. The extinction severely affected both marine benthos and plankton. Using brachiopod data as a measure of ecological change, it can be seen that the number of within‐habitat species (alpha diversity) was severely reduced and the number and distinctness of benthic communities (beta diversity) on marine shelves also declined sharply. Concurrently the number of palaeogeographic provinces fell from ten to five, possibly as a result of a loss of endemic species and preferential survival of cosmopolitan species. At the peak of extinction, following the second extinction phase, the ecological structure of both benthic and planktonic ecosystems had been severely disrupted and downgraded in complexity as a wide variety of niches were ‘vacated’. In spite of the profound biodiversity and ecological crisis within this ‘survival’ interval, communities returned to their pre‐extinction levels of alpha and beta diversity during the subsequent ‘recovery’ interval. In spite of the large amount of vacant ecospace to be filled there was very little innovation in terms of adaptive strategy, so that the structure of the emerging Silurian communities was similar to that of the Ordovician. In these terms the ecological recovery was remarkable, but it was also prolonged over about 4–5 ... Article in Journal/Newspaper Ice cap Wiley Online Library Geological Journal 36 3-4 329 340 |
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Wiley Online Library |
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crwiley |
language |
English |
description |
Abstract The high rate of species extinction in recent decades is seen by many ecologists as heralding an extinction of catastrophic magnitude in the near future. The ecological consequences of such a biodiversity crisis are hard to predict, but some indication of likely effects can be gained from the knowledge of mass extinctions in the past. The Late Ordovician extinction was one of the five great extinctions in the geological record. It occurred in two phases about 0.5–1million years (Ma) apart and resulted from climatic and related environmental changes associated with the rapid growth and decay of the large Gondwanan ice cap. Overall, an estimated 86% of species became extinct, 61% of genera and 12–24% of families, but few or no orders or higher taxa. The extinction severely affected both marine benthos and plankton. Using brachiopod data as a measure of ecological change, it can be seen that the number of within‐habitat species (alpha diversity) was severely reduced and the number and distinctness of benthic communities (beta diversity) on marine shelves also declined sharply. Concurrently the number of palaeogeographic provinces fell from ten to five, possibly as a result of a loss of endemic species and preferential survival of cosmopolitan species. At the peak of extinction, following the second extinction phase, the ecological structure of both benthic and planktonic ecosystems had been severely disrupted and downgraded in complexity as a wide variety of niches were ‘vacated’. In spite of the profound biodiversity and ecological crisis within this ‘survival’ interval, communities returned to their pre‐extinction levels of alpha and beta diversity during the subsequent ‘recovery’ interval. In spite of the large amount of vacant ecospace to be filled there was very little innovation in terms of adaptive strategy, so that the structure of the emerging Silurian communities was similar to that of the Ordovician. In these terms the ecological recovery was remarkable, but it was also prolonged over about 4–5 ... |
format |
Article in Journal/Newspaper |
author |
Brenchley, P. J. Marshall, J. D. Underwood, C. J. |
spellingShingle |
Brenchley, P. J. Marshall, J. D. Underwood, C. J. Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
author_facet |
Brenchley, P. J. Marshall, J. D. Underwood, C. J. |
author_sort |
Brenchley, P. J. |
title |
Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
title_short |
Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
title_full |
Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
title_fullStr |
Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
title_full_unstemmed |
Do all mass extinctions represent an ecological crisis? Evidence from the Late Ordovician |
title_sort |
do all mass extinctions represent an ecological crisis? evidence from the late ordovician |
publisher |
Wiley |
publishDate |
2001 |
url |
http://dx.doi.org/10.1002/gj.880 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fgj.880 https://onlinelibrary.wiley.com/doi/pdf/10.1002/gj.880 |
genre |
Ice cap |
genre_facet |
Ice cap |
op_source |
Geological Journal volume 36, issue 3-4, page 329-340 ISSN 0072-1050 1099-1034 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/gj.880 |
container_title |
Geological Journal |
container_volume |
36 |
container_issue |
3-4 |
container_start_page |
329 |
op_container_end_page |
340 |
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1811639509997060096 |