-- As estimated 50 percent of all endangered species live in the rainforest. The planet’s largest rainforest –The Amazon – lost more than 17 percent of its forest cover in the last century due to human activity.
-- Freshwater ecosystems are home to more than 100,000 known species of plants and animals, and are now one of the most endangered habitats in the world as a result of human development, pollution, and climate change.
--The world is, and always has been, in a state of flux. Over hundreds of millions of years, continents have broken apart, oceans appeared, mountains formed and worn away. With geological change come changes in living things: species, populations, and whole lineages disappear, and new ones emerge.
(From Source 2)
--Extinction is therefore a natural process. According to the fossil record, no species
has yet proved immortal; as few as 2-4% of the species that have ever lived are
believed to survive today. The remainder are extinct, the vast majority having
disappeared long before the arrival of humans.
--But the rapid loss of species we are seeing today is estimated by experts to be between 1000 and 10,000 times higher than the “background” or expected natural extinction rate (a highly conservative estimate). Unlike the mass extinction events of geological history, the current extinction phenomenon is one for which a single species - ours - appears to be almost wholly responsible. This is often referred to as “the sixth extinction crisis”, after the five known extinction waves in geological history.
--The number of species known to be threatened with extinction has topped 16,928.
18th Century
19th Century
20th Century
In October 1999 the world population hit 6 billion. Over the 20th century 157 known animal species became extinct.
21st Century
To date there are nearly 7 billion people on earth. This is set to peak at 9 or 10 billion. So far approximately 6 animal species have become extinct. Since we only know a small proportion of the species that exist, this number is likely to be much higher.
(From Source 4/5)
More than 90 percent of all organisms that have ever lived on Earth are extinct. As new species evolve to fit ever changing ecological niches, older species fade away. The rate of extinction is far from constant. At least a handful of times in the last 500 million years, 50 to more than 90 percent of all species on Earth have disappeared in a geological blink of the eye.
Today, many scientists think the evidence indicates a sixth mass extinction is under way. The blame for this one, perhaps the fastest in Earth's history, falls firmly on the shoulders of humans. By the year 2100, human activities such as pollution, land clearing, and overfishing may have driven more than half of the world's marine and land species to extinction.
--Although extinction is a natural occurrence it is estimated that the current extinction rate on the planet is between 1000 and 10,000 times higher than the expected natural extinction rate. In recent history, extinction of animals have occurred because go Humans.
--But the rapid loss of species we are seeing today is estimated by experts to be between 1000 and 10,000 times higher than the “background” or expected natural extinction rate (a highly conservative estimate). Unlike the mass extinction events of geological history, the current extinction phenomenon is one for which a single species - ours - appears to be almost wholly responsible. This is often referred to as “the sixth extinction crisis”, after the five known extinction waves in geological history.
--The number of species known to be threatened with extinction has topped 16,928.
(From Source 3)
17th Century
By the middle of the century there were about 450 million humans on earth and 7 animal species became extinct.
18th Century
550 million humans on earth and 11 more species became extinct by mid-century.
19th Century
By 1850 the human population had increased to 900 million and 27 species were lost.
20th Century
21st Century
To date there are nearly 7 billion people on earth. This is set to peak at 9 or 10 billion. So far approximately 6 animal species have become extinct. Since we only know a small proportion of the species that exist, this number is likely to be much higher.
(From Source 4/5)
More than 90 percent of all organisms that have ever lived on Earth are extinct. As new species evolve to fit ever changing ecological niches, older species fade away. The rate of extinction is far from constant. At least a handful of times in the last 500 million years, 50 to more than 90 percent of all species on Earth have disappeared in a geological blink of the eye.
Today, many scientists think the evidence indicates a sixth mass extinction is under way. The blame for this one, perhaps the fastest in Earth's history, falls firmly on the shoulders of humans. By the year 2100, human activities such as pollution, land clearing, and overfishing may have driven more than half of the world's marine and land species to extinction.
Source 1 (http://www.dosomething.org/tipsandtools/11-facts-about-endangered-species)
Source 2 (http://cmsdata.iucn.org/downloads/species_extinction_05_2007.pdf)
Source 3 (http://www.ypte.org.uk/environmental/extinction/27)
Source 4 (http://science.nationalgeographic.com/science/prehistoric-world/mass-extinction/)
Source 5 (http://www.discoveryuk.com/the-loop/extinction-facts/)
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