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The unlikely role of dinosaurs in the diversity discourse

Catastrophic Thinking: Extinction and the Value of Diversity from Darwin to the Anthropocene

David Sepkoski
University of Chicago Press
360 pp.
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Who would disagree that diversity is a good thing? The United Nations has promoted biological and cultural diversity as ideals for decades. Scientific American has asserted that diversity is essential for excellence (1). Countries such as Qatar, where I live, have put much effort into diversifying their economies. McKinsey and Company, a firm hardly known for being at the forefront of social justice, has found that businesses with more diverse workforces perform better financially (2). To be sure, promoters of equity and inclusion have also been described by critics as forming part of a diversity “machine” (3) or “industry” (4). However, most of us probably value plurality and variety.

Where does our appreciation of diversity come from? In his new book, Catastrophic Thinking, historian of paleontology David Sepkoski answers this question by delving into our collective imagination of the deep past. He quotes from archival documents and scientific reports and considers apocalyptic fiction in his analysis. While the tone of the narrative remains as serious as the topic, references to popular culture make it accessible.

Sepkoski argues that the increase in diversity discourse that began in the 1980s was linked to the discovery that sudden extinction events, such as the one at the Cretaceous–Tertiary boundary more than 60 million years ago, could drastically reduce the number of species on Earth. In such a scenario, the normal rules of natural selection do not apply. Entire taxa could disappear within a short period of time through no fault of their own. Paleontologists thus reimagined life on Earth as precarious, and they recognized mass extinctions in the fossil record as the cause of sudden drops in diversity.

This “new catastrophism” of the late 20th century was different from the Darwinian understanding of extinction as a gradual and inevitable process in which natural competition slowly weeded out the unfit. In the struggle for life, Charles Darwin and his successors thought that declines in some populations were simply making way for those that were better adapted to particular habitats. As new species replaced older ones, nature was perceived to be in balance, if not on a path of improvement. Conservation efforts during this period were thus confined to charismatic animals, with little consideration to broader biological diversity.

Sepkoski draws on distinctive personal insights into the research on extinction events to frame his narrative. The son of Jack Sepkoski, a University of Chicago paleontologist who was a central figure in extinction research in the 1970s and 1980s, he writes with deep familiarity tempered by professional distance. His father, we learn, combined a fascination for fossils with a knack for mathematical methods and a dedication to long-term data collection. Over the course of a decade, the elder Sepkoski built the first computerized record of marine fossils. Published in 1982, this database revealed larger patterns of diversification and extinction.

Sepkoski acknowledges that “new catas­trophism” is not the only explanation for the rise in popularity of the concept of diversity. Contemporary debates about equity and inclusion, for example, are rooted in longer political, economic, and legal histories that fall outside the purview of this book. Nevertheless, he convincingly demonstrates that an ecological perspective has profoundly shaped our views of biological and social communities. From the 1980s onward, global conservation efforts aimed at biodiversity, and cultural diversity soon gained traction.

Sepkoski’s magisterial work will hopefully serve as an inspiration for more comprehensive histories of the concept of diversity. While very detailed, his narrative focuses on Western voices. Undoubtedly, those on the receiving end of European imperialism had visions of catastrophic collapse long before the specter of mass extinction became part of broader science and culture. This shortcoming aside, Catastrophic Thinking is essential reading for those seeking to understand the origin of one of the most powerful concepts under consideration today.

References and Notes:
1. F. Guterl, Scientific American, 1 October 2014.
2. V. Hunt, D. Layton, S. Prince, “Why diversity matters,” McKinsey and Company, 1 January 2015.
3. F. R. Lynch, Society 34, 32 (1997).
4. A. Gardner, Areo, 10 September 2019.

About the author

The reviewer is at the Department of Liberal Arts and Sciences, Virginia Commonwealth University School of the Arts in Qatar, Doha, Qatar.