“The World Without Us,” by Alan Weisman, explores what would happen if the Human population ceased to exist overnight. Here’s the timeline….

After two days
With no one to run the pumps, New York subways flood.

Seven days
Generators that cool nuclear reactor cores run out of fuel.

One year
Human head and body lice grow extinct. Wildlife returns to sites of melted-down nuclear reactors.

Three years
In colder climes, walls and roofs start to separate, pipes burst, roaches die.

20years
Panama Canal closes up. Garden vegetables revert to wild strains.

100 years
Feral housecats devastate populations of small predators. Elephant population grows 20-fold as ivory trade ceases.

300 years
New York bridges fall, dams fail worldwide, cities built in river deltas, such as Houston, wash away.

500 years
Forests overtake suburbs in temperate climes, but plastic and metal debris remain.

Thousands of years
Underground structures such as the Chunnel across the English Channel are the last intact human-made structures.

35,000 years
Lead deposited by smokestacks finally is cleansed from the soil.

100,000 years
Carbon dioxide returns to prehuman levels — maybe.

Hundreds of thousands of years
Microbes evolve to eat plastic.

7.2 million years
Traces of Mount Rushmore images remain. PCBs and other toxins remain but are buried.

10.2 million years
Bronze sculptures are still recognizable.

3 billion years
Life still thrives on Earth, in new forms.

4.5 billion years
Depleted Uranium-238 reaches its half-life. Earth begins to warm as sun expands.

5-plus billion years
Earth burns as dying sun swells to envelop inner planets.

Forever
(via Seattle Post)