Animal Extinction - What is an Animal Extinction?

We Are In the Middle of a Mass Extinction, Scientists Warn

Protesters with sign
Protesters make the point that humans are not the only animals on earth. We just act like it. Getty Images

This article was updated and re-written in part by 
Michelle A. Rivera, About.Com Animal Rights Expert

The extinction of an animal species occurs when the last individual member of that species dies. Although a species may be "extinct in the wild," the species is not extinct until every individual, regardless of location, captivity, or ability to breed, has died.

The extinction of dodo bird is usually blamed on overhunting.

But some species became extinct from natural causes. This could happen when predators are more powerful and plentiful than the animals on which they prey or when there is a severe climate change that makes the territory on which they live uninhabitable. But other animals, such as the passenger pigeon, become extinct due to man-made loss of habitat and over hunting.  

Endangered Species International estimates that 99.9 percent of the animals that ever existed on earth have become extinct due to catastrophic events that happened while the Earth was evolving. When these events cause animals to die, it’s called a mass extinction. There have been five mass extinctions due to natural cataclysmic events. In one, a volcano so large erupted and cause lava to spew into the air, releasing toxins that fell into the sea killing 20 per cent of marine animals. In another, scientists believe a meteor or comet crashed in Mexico’s Yucatán Peninsula.

Glaciers also caused animals to die off in large numbers, wiping out species because of climate change that caused the ice to harden and the sea levels to drop. Needless to say, this event wiped out much of the ocean’s creatures. Scientists agree that there are many unresolved mysteries surrounding mass extinctions.

One theory for a mass extinction over 250 million years ago was the presence of large waves of lava forming over Russia which killed 90 percent of all species on earth; another theory is that particular mass extinction was caused by an asteroid, but no crater exists so the argument continues.

And while this all sounds like it happened in the dinosaur ages, some scientists believe that a mass extinction is taking place right now. Biologists have been raising the alarm. They believe Earth is undergoing a sixth mass extinction of both flora and fauna. There have been no mass extinctions in the past half-billion years, but now that humans have taken over the Earth, extinctions are happening at an alarming rate. Extinction is something that occurs in nature, but not in the large numbers we are seeing today. A normal rate of extinction, due to natural causes, is 1 to 5 species annually.

But we’re humans, so we need to go bigger, right? With human beings in the picture, we are losing plant, animal and insect species at an alarmingly rapid rate. Scientists at the Center For Biological Diversity estimate that the rate is a thousand more, or even ten thousand more, than the 1 to 5. They believe dozens of animals are going extinct every single day.

The largest species by far rapidly heading toward extinction are amphibians.  When frogs and other amphibians start to die off in large numbers, other species fall like dominoes. Save the Frogs, an organization dedicated to understanding the threat to frogs and to stopping the massive loss of amphibians, estimates a third of the species are already on the threshold of going extinct. They are aggressively attempting to get the attention of the public and bring lawyers, politicians, teachers and especially the media to educate the public on the disastrous affect the mass extinction of a third of a species of amphibians will have on the health and well-being of our planet.

Chief Seattle, was a popular and well-known character and a member of a tribe of Native Americans from the Pacific Northwest.

He was especially notorious for his love of the environment and the people’s responsibility towards stewardship. He knew in 1854 that a crisis was on the horizon. He wrote “What is there to life if a man cannot hear the cry of a whippoorwill or the arguments of the frogs around a pond at night?”