Warp Speed Extinction

Throughout life's history, there has always been a low level of extinction. This is called background extinction. It is like low music playing while you do your homework. As species die off, new species evolve a bit faster. The fossil record shows how the diversity of life has always increased.

Mass extinction is very different from background extinction. It is like a sudden, startling blare of music. Many species suddenly die, and new species do not evolve fast enough to take their place. Today, species are dying off at warp speeds—1,000 to 10,000 times the speed of background extinction. As in times of mass extinction, evolution is having trouble keeping up. The biodiversity on the planet is decreasing at an alarming pace. At the current rate, scientists predict that one out of every five animals and plants on the Earth will become extinct within the next 25 years! Some say this is a low number, and project that nearly half of all life on the planet will become extinct during this short amount of time.

The greatest threat to the world's living creatures is the destruc-

FOSSIL FUELS

Coal, oil, and gas are called "fossil fuels" because they have been formed from the fossilized remains of prehistoric plants and animals. They provide about 95% of the world's energy for such needs as heating, transportation, electricity, and more. Fossil fuels are not a renewable energy source. Once they are gone, they are gone forever. You could argue that fossil fuels are renewable because life on the planet will eventually die and become fossils. However, it took millions of

Mammoths became extinct about 1 1,000 years ago. Many scientists speculate that early humans hunted these ancestors of our modern elephant into extinction, but climate change or disease may also have contributed to their demise.

tion of their habitats. Natural habitats all around the world are cut down or paved over as the human population expands. For example, over half of every animal and plant species in the entire world lives in the warm tropical forests in Australia, Asia, Africa, Mexico, and South America. Each year the Earth's forests shrink

What do pandas, monkeys, and frogs have in common? Habitat destruction. People are kicking them out of their homes! People are building more cities and taking over natural spaces, such as rain forests and wetlands. As animals lose their homes and their food supply, their survival is at stake.

by more than 40 million acres.

In addition, human populations create more waste than the Earth can absorb. The result is pollution. Poisonous chemicals have polluted our air and water, killing numerous species of wildlife either directly or by devastating their habitats. The cycle of evolution does not stop. The choices are to adapt or perish. Many species have or will become extinct.

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