We are ‘on the brink’ of a sixth great extinction as plants and animals die out 1,000 times faster than before humans arrived

map_species

A map of the distribution of threatened bird species in the Americas, showing their concentration in the coastal forests of Brazil and in the northern Andes. Red means more species.

‘We are on the verge of the sixth extinction,’ Pimm said from research at the Dry Tortugas.
‘Whether we avoid it or not will depend on our actions.’

HOW THEY DID IT

The study focused on the rate, not the number, of species disappearing from Earth
It calculated a ‘death rate’ of how many species become extinct each year out of 1 million species.
In 1995, Pimm found that the pre-human rate of extinctions on Earth was about 1.
But taking into account new research, Pimm and his colleagues refined that background rate to about 0.1.
Now, that death rate is about 100 to 1,000, Pimm said.
The work, published Thursday by the journal Science, was hailed as a landmark study by outside experts.
Pimm’s study focused on the rate, not the number, of species disappearing from Earth.
It calculated a ‘death rate’ of how many species become extinct each year out of 1 million species.
In 1995, Pimm found that the pre-human rate of extinctions on Earth was about 1.
But taking into account new research, Pimm and his colleagues refined that background rate to about 0.1.
Now, that death rate is about 100 to 1,000, Pimm said.

golden_lion_tamarin

THE FIVE GREAT EXTINCTION EVENTS
Five times, a vast majority of the world’s life has been snuffed out in what have been called mass extinctions, often associated with giant meteor strikes.

End-Ordovician mass extinction
The first of the traditional big five extinction events, around 440 million years ago, was probably the second most severe. Virtually all life was in the sea at the time and around 85% of these species vanished.

Late Devonian mass extinction
About 375-359 million years ago, major environmental changes caused a drawn-out extinction event that wiped out major fish groups and stopped new coral reefs forming for 100 million years.

End-Permian mass extinction (the Great Dying)
The largest extinction event and the one that affected the Earth’s ecology most profoundly took place 252 million years ago. As much as 97% of species that leave a fossil record disappeared forever.
End-Triassic mass extinction
Dinosaurs first appeared in the Early Triassic, but large amphibians and mammal-like reptiles were the dominant land animals. The rapid mass extinction that occurred 201 million years ago changed that.

End-Cretaceous mass extinction
An asteroid slammed down on Earth 66 million years ago, and is often blamed for ending the reign of the dinosaurs.

One Response to “We are ‘on the brink’ of a sixth great extinction as plants and animals die out 1,000 times faster than before humans arrived”

If you wish you can Leave a Reply. We will publish it after moderation. Insults and Spam are automatically deleted. Thank you for visiting my blog today.

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: