Half-Earth: Our Planet’s Fight for Life

Wilson turns his focus to the necessity of restoration, “meaning human intervention” (175), for conservation projects. These conservation projects start with “a few individuals [who] push forward, risking failure and harm to their own security and reputations” and who “have a dream that does not fit the norm” (176). Their success becomes “part of environmental history” (176).

Wilson provides two examples of conservation pioneers. In the first example, MC Davis, a successful business entrepreneur, outdoorsman, and native to the Florida Panhandle, worked to restore the longleaf pine in the Florida Panhandle woodlands. This species was the dominant tree species of the southern US wildlands prior to the arrival of Europeans. Its disappearance destabilized the Panhandle’s biodiversity and made its understory more prone to fire. Davis also argued for a wildlife corridor along the Gulf of Mexico coast, which Wilson notes is under way. 

Similarly, Gregory C. Carr is another successful business entrepreneur who helped restore Gorongosa National Park in Mozambique. Civil war and poaching had decimated the park’s biodiversity. Carr rebuilt the main camp, added a laboratory and museum to study the animals and plants, and “gave high priority to the welfare of people living in and around Gorongosa” (180), providing employment opportunities at the park and building a school and clinic.

There is one main challenge to restoration, according to Wilson, and that is determining biodiversity’s baseline. Ecosystems and the species within them change over time. Anthropocentrists argue that these changes support their view that environments can re-stabilize with invasive species. Wilson disagrees and argues that conservation projects need to analyze past species to detect major changes to the ecosystem. To Wilson, “the species composition immediately prior to the first major shift ascribed to human activity on the basis of fossil and present-day evidence is the baseline” (182).

Wilson turns to developing his central tenet, positing that “the crucial factor in the life and death of species is the amount of suitable habitat left to them” (185-86). Changes in habitat size impact the number of species found within the habitat. Wilson argues that his half-earth solution will protect 85% of species worldwide. This percent could increase if hot spots are included. Current nature preserves cover 15% and 3% of land area and ocean area, respectively. While the number of nature preserves is increasing, Wilson argues that these “piecemeal operations” are not enough to save the planet’s biodiversity. To Wilson, designating one-half of the global surface to nature is the only solution that meets the magnitude of the problem.

To Wilson, the half-earth solution does not mean re-dividing the planet into new countries or states or changing ownership of these areas. Rather, the key to his solution is to reduce our ecological footprint. As part of this solution, human populations across the planet will need to reach the zero-growth threshold, meaning that population ceases to increase. Per-capita consumption will also need to decrease. Wilson suggests that this has already begun due to improvements in technology that are reducing resource use, moving economies towards renewable resources rather than fossil fuels, reducing travel needs, and improving the productivity of agriculture. Big data and neuroscience can also help scientists understand “how all these minds [of living beings] and the decision-making devices within and around them evolve, and how they interact with ecosystems” (206).

Humans and the rest of Earth’s life, according to Wilson, are in the “middle of a bottleneck of rising population, shrinking resources, and disappearing species” (205). To Wilson, because we are stewards of the natural world, we have not only an economic imperative, but also a moral and ethical imperative to stop its destruction and end the Sixth Extinction. With space and security, Wilson believes that we can save biodiversity.

Wilson reminds his audience of the dangers of humanity’s preference for short-term decisions that are selfish and short-sighted, which makes it “difficult to protect distant environments” (209). However, Wilson asserts that there is “an instinct for true altruism” (209), such that humans can be completely selfless and have no desire for their own gain. Altruism is driven by the evolutionary force known as group selection, by which individuals will act altruistically towards members of their own group, even if there is a cost to themselves, because it will contribute to the group’s success. To Wilson, there must be a “major shift in moral reasoning” such that humans view all species as our own kin or group (211). Humans must recognize that, like other species, we are also a product of the biological world. Our survival depends on us grasping that “we are the mind and stewards of the living world,” which means we “do no further harm to the biosphere” (212).