In Chapter 2 of The World Without Us, Weisman explains what would happen if we were to leave our homes and never return. This video shows exactly that.

Within 10 years: Moss begins growing over the roof.
15 years: Ants, cockroaches, and other bugs take over the house. Termites chew at the foundation.
20 years: Roof starts to come apart- shingles fall off.
25 years: Nails can no longer hold together the floorboards.
30 years: Paint deteriorates and bare walls are exposed.
35 years: Grass, mushrooms, fungi, and other plants begin to take over lawn and crack the concrete.
100 years: Animals invade the house and surrounding area.
125 years: Plant growth causes the house to collapse.
175 years: Debris from the collapse is broken down by weather and plants. All that remains is the chimney and metal parts.
240 years: Rain wears down the metal, causing it to rust and crumble. Chimney still remains.
250 years: Chimney begins to crumble.
300 years: Plants break down the crumbled metal remains and roof shingles.
340 years: Trees and larger flora surrounding the house continue to grow, and chimney continues to crumble.
390 years: Metal fence is broken down by weather.
500 years: No part of the house is left standing. Some parts float down a nearby river.

Chapter 5: Before the existence of man on the North American continent, there were many other species that exceeded the the average size of mammals today. Most were about the size of a now-extinct mammoth, which was a little bigger than an elephant. But we were also home to such animals as giant sloths weighing more than fourteen thousand pounds. Thomas Jefferson had a huge fascination with large prehistoric animals. One of the reasons he sent Lewis and Clark off to search the land was to see if they could find large animals like the giant sloth.  Many people think that the ice age killed off most of these mammals, however this can't be true because they would have responded the same way that humans did- by moving south to warmer weather. The only other hypothesis is that man started to kill off the larger animals for the sole reason that they were bigger. They were easier to kill and provided humans with enough meat to last a while.

Chapter 6: In this chapter, "The African Paradox," Weisman explains about digs in eastern Africa. The digs show that 992,000 to 493,000 years ago, a lake in the Great Riff Valley was once inhabited by humans. This suggests that with the change of land use, human traces can be covered up. But traces can be discovered, as archaeologists have found tools made out of animal bones. But the world without them in this area has changed almost back to normal, resuming it's natural state before man arrived.

Chapter 7: After a civil war ended on the island of Cyprus, many buildings were either destroyed or evacuated. The results of this abandonment were animals taking over buildings and plants growing out of sand blown in from the neighboring beach. All of the features built by humans on this island are being demolished, not by any manmade force, but by nature. It will take a long time, but the end result will be an island that is free of anything that is related to man.

Chapter 8: Many years ago in the time of the Roman Empire, buildings were open and were made out of concrete. If struck by an earthquake, the buildings would remain intact because the pillars were so strong that the building didn't fall. Today it is a different story. Many buildings are being built on top of old foundations that were meant for one story stores or restaurants. The weight of the buildings crushes the foundation during an earthquake.
In this chapter, Weisman also talks about how Istanbul wants to create a subway system that will link Europe and Asia. But during a dig, archaeologists discovered ancient tunnels dug out of tuff, which is a soft volcanic rock. These tunnels show that even before modern technologies, ancient civilizations could connect underground cities together for protection from enemies.

Chapter 9: While doing research on the coast of Great Britain, one scientist found tiny plastic beads in the sand. After examining and researching, they found that these beads come from soaps and shampoos that contain the marketed "bacteria fighting pellets." After washing these pellets down the drain, they eventually make their way to the ocean where more than 5.5 quadrillion or 250 billion pounds of pellets are floating. These beads are swallowed by krill and plankton, clogging their intestines and killing them. This destroys natural earth processes because the whole food chain begins with these little sea creatures.

Chapter 10: Tires from old cars are made from a polymer called elastomer. This polymer is a material that was not created by nature, nor has nature created a microbe that is able to destroy it. Tires can be recycled and made into something else, but if they aren't they will last forever. In our lifetime almost one trillion tires will be put out of use and they will sit there until an organism is created. The only way for nature to create an organism is for the tires to be out in the sunlight so photosynthesis can take place.

Oddly, it seems that humanity’s greatest achievements— skyscrapers, statues, etc.— are the least permanent, while trash, plastic, and oil— the detritus of civilization— are the most permanent. It is hard to picture the world without concrete mazes and metal highrises. Although no one currently living has ever seen the earth as it was thousands or even hundreds of years ago, it is not an impossible thing to imagine. People feel this sort of primal nostalgia for something that we know we have lost, even though most of us have never seen it. When Weisman describes his visit to the Bialowieza Puszcza, he says that although he has never seen a forest as complete as that one, it didn't feel strange to him; rather, it felt recognizable.
Weisman tries to touch upon this feeling throughout the book. While the things that he describes will happen to our planet are far-reaching and not likely to happen any time soon, it is easy to picture these things happening. And this provokes a profound response to the reader because it is something happen right in their very own home. This book makes for a thoughtful, sometimes depressing, but always fascinating read, and I am looking forward to reading more.

Chapter 1: The book begins by telling about the only half-million acres of Earth that has remained untouched by humans for its entire existence. This place is called Bialowieza Puszcza, which is Polish for "forest primeval." There is ten times more biodiversity here than in any other forest, and more species and overall kinds of life than anywhere else on the continent. The forest is described as reminiscent of a fairy tale story, with trees 150 feet tall and diameters of seven feet. This chapter was short, so I believe that it's just a summary of what the book is becoming and how something with such little human interaction could stay so perfect for so long.

Chapter 2: This chapter really caught my attention, and put the book into perspective for me. The author states that humans are merely visitors on this earth, and that the earth wants our respect. Weisman goes on to describe how the earth breaks down the materials that our found in our houses. This entire process of a house decomposing throughout many years is mainly caused by water, because it "always wants in." It breaks everything except for bathroom tiles because of the chemical properties of their fired ceramic. The cycle our planet undergoes is amazing because it's always starting fresh; tearing down the things that are old and weak and in the same spot replacing it with a youthful one, with many years of growth ahead of it. Weisman says that the earth would return to its natural state if humans ceased to exist. The only way to tell that humans were ever there would be fire hydrants

Chapter 3: This chapter is called "The City Without Us." Weisman describes the process that nature would undergo in order to restore itself to the way it was before anyone had tampered with it. Before the land was settled by immigrants, present day New York was covered by huge pine and oak trees, with hundreds of streams and a river running through the area. Then humans filled them all with dirt and created water management systems. Underneath the city is a huge flow of water that the subway stations have to hold back daily. Even now when man is thriving in the city, when there is heavy rain the subway risks flooding. It's almost as if nature is fighting back, always giving us reasons to leave it alone.

Chapter 4: Weisman begins this chapter with the alarming fact that a glacier is due to flatten Manhattan any day now since the last glacier left 11,000 years ago, although scientists are doubting it will come on time due to increased levels of carbon dioxide. Until around 200 years ago, carbon dioxide from the gaseous part above the atmosphere dissolved into the liquid part (atmosphere and oceans) below at a steady rate, keeping the world at equilibrium. Now that the carbon dioxide levels are so high, the ocean needs to readjust. Weisman points out that if we continue to increase our carbon emissions, Greenland will melt and turn Manhattan into just a few islets at its highest altitudes. Evolution is discussed towards the end of this chapter, where Weisman questions whether there is potential that another species, such as a lion, could have evolved as we did from apes, and have hegemony over Homo sapiens.