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Edward O. Wilson, The Diversity of Life, (1992)

origins | details of the current problem

"Climb into the tangle of fallen vegetation, tear away pieces of rotting bark, roll over logs, and you will see these creatures teeming everywhere. As the pioneer vegetation grows denser, the deepening shade and the higher humidity again favor old forest species, and their saplings sprout and grow. Within a hundred years the gap specialists will be phased out by competition for light, and the tall storied forest will close completely over."

EOW, p. 11

"Human demographic success has brought the world to this crisis of biodiversity....Our species appropriates between 20 and 40 percent of the solar energy captured in organic material by land plants. There is no way we can draw upon the resources of the planet to such a degree without drastically reducing the state of most other species."

EOW, p. 272

"In the next thirty years, the world would lose not only half its forest cover but nearly half of the forest species.

EOW, p. 278

"If it is granted that biodiversity is at high risk, what is to be done? The solution will require cooperation among professions long separated by academic and practical tradition."

p. 312

"So we should try to expand reserves from 4.3 percent to 10 percent of the land surface, to include many of the undisturbed habitats as possible with priority given to the world's hot spots."

p. 337

"Because scientists have yet to put names on most kinds of organisms, and because they entertain only a vague idea of how ecosystems work, it is reckless to suppose that biodiversity can be diminished indefinitely without threatening humanity itself. Field studies show that as biodiversity is reduced, so is the services provided by ecosystems.... These services are important to human welfare."

p. 347-48

"Only in the last moment of human history has the delusion arisen that people can flourish apart from the rest of the living world."

p. 349

Origins of diversity are complex:

He describes:

"The most wonderful mystery of life may well be the means by which it created so much diversity from so little physical matter. The biosphere, all organisms combined, makes up only about one part in ten billion of the earth's mass.… Yet life has divided into millions of species, the fundamental units, each playing a unique role in relation to the whole."


Great extinctions created the world we inhabit:

540 mil. years ago oxygen levels > to comprise the current 21% of air!

Ordovician -- first worldwide ecosystem collapse, cessation of reef building!

450 mil. years ago the first plants colonized the dry land; insects followed

Devonian -- another worldwide collapse -- end of reef building, 90% extinction.
terrestrial flora & fauna emerge
age of fishes; the Devonian 405 mi. years ago

age of insects; the Carboniferous 310 mi. years ago

Permian -- 54% of the families perished; 77-96% of all marine organisms
it took over 10 million years for reef building organisms to rebound!
age of reptiles; the Mesozoic 230 mi. years ago

Cretaceous -- 1/3 of all families perished; dinosaurs, trilobites, & ammonites gone
60% of all species perished

age of mammals; the Cenozoic 60 mi. years ago
age of primates; the Plio-pleistocene 2 mi. years ago

Pleistocene -- large animals died out: saber toothed tigers, mammoths, & sloths

"This is the assembly of life that took a billion years to evolve. It has eaten the storms -- folded them into its genes and created the world that created us. It holds the world steady."


More on the importance and meaning of biological diversity

EOW: Edward O. Wilson, The Diversity of Life, [New York: W. W. Norton, 1992].


Critic of Wilson's narrow view of consilience, Laura D. Walls, biographer of Thoreau.

Walls book on Thoreau.

Authors | Ideas | bottleneck | ecology | life's diversity | biology

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Last Updated on 02/18/2008 .