Half-Earth

Wilson is a scientist and a long-time ardent proponent of saving our planet. He has deep concerns for our biosphere and advocates setting aside half the earth for the natural world. Wilson lays down solid evidence for his worries, and I came away from the book nodding my head in agreement.

My takeaways from Half-Earth:

Many scientists believe man has had such a profound impact on the planet that we should acknowledge the end of the Holocene Epoch and replace it with the Anthropocene, the Epoch of Man.

Apocalyptic extinctions are rare in the history of life, occurring only at about hundred-million year intervals. The planet usually required ten million years to recover from each. Our current peak of destruction initiated by humanity is often called the Sixth Extinction.

A census of biodiversity is currently in the process of being taken. It is believed that the total will be much higher than the two million species so far discovered.

Nothing causes the destruction of a biosphere as invasive species. It is generally believed that before the coming of humanity about two hundred thousand years ago, the rate of origin of new species per extinction of exiting species was about one species per million species per year. But, due to human activity, it is believed that currently the rate of extension overall is between a hundred and a thousand times higher than it originally was. The rate of extinction is rising in most parts of the world, with the preeminent sites of biodiversity loss being the tropical forests and coral reefs. If ninety percent of a forest is cut, about half of the species will soon disappear. Hawaii has been universally acknowledged as the extinction capital of the world.

Scientists use the acronym HIPPO for a quick list of our most ruinous activities: Habitat destruction, invasive species, pollution, population growth, and overhunting.

Most experts agree that humanity has raised the concentration of greenhouse gasses, especially carbon dioxide and methane, to a dangerous level. Predictions for the future are generally agreed upon: historic heat records will become routine; severe storms and weather anomalies will be normal; the melting of the ice shields will accelerate; the sea levels will rise exponentially.

There are those who are considered Anthropocene optimists, who feel a human-centered world is a good thing and a desirable outcome.

A lot to think about.