We are Living in

The Age of Humans

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Earth is changing rapidly, and an increasing number of scientists say that humans have become the dominant force driving these changes. While the term has no formal definition, many agree that we are now living in an age shaped by human activity: the Anthropocene.

Evidence for the Anthropocene ranges from worldwide population booms to the expansive transformation of the landscape. But solutions are cropping up at the local level that could help create a more resilient global community.

Explore the maps below to see an atlas of human influences, as well as the cities that are helping to re-shape the way our species interacts with the planet.

Mapping the Scope of Human Influence

The following maps show the current reach of human activity, as detected by satellites or in data compiled and analyzed by specialists. Zoom in to see more details about a particular region, or click the selected examples.

7.25 billion people inhabit the Earth

people inhabit the Earth as of 2014, according to the U.S. Census Bureau. By 2050, the population is expected to total between 8.3 and 10.9 billion.

But population is distributed unevenly across the globe, as showcased by the density map at left. About 2.5 billion people reside in just two countries: China and India. In addition, people have been increasingly migrating into cities, creating a boom in dense urban areas and sparking a rise in megacities—cities of 10 million people or more. Although global birth rates are in decline, life expectancies have dramatically increased. Meanwhile, increasing affluence in many countries means that consumption of natural resources is rising even faster than population growth.

CLICK on the locations below to explore these densely populated areas:

Manilla, Philippines is the world's most densely populated city, with more than 1.6 million people packed into an area of about 15 square miles.

India's Ganges River supports hundreds of millions of people in a dense network of cities, villages and small farms. The city of Patna stretches for about 9 miles along the southern shore of the Ganges.

Humans influence nearly every corner of the Earth

of Earth's land surface outside of ice sheets is managed by humans.

The map at left, developed by the Wildlife Conservation Society, reflects patterns of roads, urban concentrations, agriculture and other factors to show the extent of human modification of the landscape. Green represents minimal human impact; orange, red and purple reflect a high degree of human activity.

CLICK on the locations below to see examples of highly managed landscapes:

The Netherlands is home to this geometric array of fIelds and villages called the Zuiderzeewerken, an expanse of reclaimed land created by diking and draining portions of the Zuiderzee, a shallow inlet of the North Sea.

British Columbia, Canada has been transformed by intensive clear-cut logging. Vast woodland tracts in western Canada and the United States have become "factory forests" for producing lumber, much of which feeds Chinese markets

Food production consumes vast tracts of land

of Earth's land area is used for agriculture. As population has increased, demand for food has skyrocketed.

Converting natural lands to farms has transformed biologically diverse habitats into vast stretches of single crops and has caused dramatic increases in water use. The map at left shows how agricultural productivity varies widely, based on the amount of calories produced. (Courtesy of the University of Minnesota Center on the Environment)

CLICK the location below to see an example of the spread of agriculture:

Saudi Arabia began to use center-pivot irrigation to grow crops in the desert in 1990. This type of agriculture "mines" groundwater, often at rates far faster than natural processes are able to replenish it. By 2010 center-pivot irrigation had increased dramatically.

Half of the world's forests have been lost

of the world's forests have been lost.

The World Resources Institute's Global Forest Watch tracks the state of forests worldwide. Shown by the map at left, human influences have degraded, fragmented or completely destroyed forests worldwide.

CLICK on the locations below to see how forests have been lost and returned:

Brazilian rain forests have been cleared in patterns that follow roads, many of them illegal. Loss of tropical rain forest threatens diverse communities of plants and animals and reduces the amount of carbon dioxide removed from the atmosphere.

New England and other parts of the eastern United States saw their forests largely denuded in the 18th and 19th centuries, but as agricultural lands were abandoned for more fertile areas to the west, large tracts have returned to woodland.

Human-induced extinctions are increasing rapidly

times above normal, or background, levels.

Studies of biodiversity suggest that human-induced extinctions will rival the great mass extinctions of prehistory, including the one that wiped out the large dinosaurs.

Biodiversity hotspots, mapped by Conservation International, are the richest and most threatened reservoirs of natural diversity. They cover only 2.3 percent of the world's land yet contain a high number of plant and animal species. For instance, the Hawaiian islands are rich in diversity but are particularly vulnerable to extinctions caused by the introduction of non-native plants and animals. According to the American Bird Conservancy, 71 of Hawaii's endemic bird species are already extinct; only 31 species remain.

**CLICK HERE** to explore a gallery of extinct animals around the globe; click a red marker to find out more about each animal.

More than 10% of the world's land area is protected

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of the world's land area is protected

The World Database of Protected Areas, compiled and maintained by IUCN, shows regions on land and sea that have been set aside as natural environments.

While the goal is to save some wild places from human modification, not all protected areas are created equal, and not all places have the resources to enforce protection. Many reserves, especially in developing countries, are still subject to illegal logging, mining and poaching, especially in the tropics.

CLICK on the green and blue areas to explore some of the world’s protected places.

We are Living in The Age of Humans

Mapping the Scope of Human Influence

7.25 billion people inhabit the Earth

Humans influence nearly every corner of the Earth

Food production consumes vast tracts of land

Half of the world's forests have been lost

Human-induced extinctions are increasing rapidly

More than 10% of the world's land area is protected

We are Living in The Age of Humans

Mapping the Scope of Human Influence

7.25 billion people inhabit the Earth

Humans influence nearly every corner of the Earth

Food production consumes vast tracts of land

Half of the world's forests have been lost

Human-induced extinctions are increasing rapidly

More than 10% of the world's land area is protected

We are Living in

The Age of Humans