Featured Research

from universities, journals, and other organizations

Extinction Rate Across The Globe Reaches Historical Proportions

Date:
January 10, 2002
Source:
University Of Texas, Austin
Summary:
Half of all living bird and mammal species will be gone within 200 or 300 years, according to a botany professor at The University of Texas at Austin.

AUSTIN, Texas -- Half of all living bird and mammal species will be gone within 200 or 300 years, according to a botany professor at The University of Texas at Austin.

Related Articles


Although the extinction of various species is a natural phenomenon, the rate of extinction occurring in today's world is exceptional -- as many as 100 to1,000 times greater than normal, Dr. Donald A. Levin said in the January-February issue of American Scientist magazine. The co-author is Levin's son, Phillip S. Levin, a National Marine Fisheries Service biologist who is an expert on the demography of fish, especially salmon.

Levin's column noted that on average, a distinct species of plant or animal becomes extinct every 20 minutes. Donald Levin, who works in the section of integrative biology in the College of Natural Sciences, said research shows the rate of current loss is highly unusual -- clearly qualifying the present period as one of the six great periods of mass extinction in the history of Earth.

"The numbers are grim," he said. "Some 2,000 species of Pacific Island birds (about 15 percent of the world total) have gone extinct since human colonization. Roughly 20 of the 297 known mussel and clam species and 40 of about 950 fishes have perished in North America in the last century. The globe has experienced similar waves of destruction just five times in the past."

Biological diversity ultimately recovered after each of the five past mass extinctions, probably requiring several million years in each instance. As for today's mass extinction, Levin said some ecologists believe the low level of species diversity may become a permanent state, especially if vast tracts of wilderness area are destroyed.

Other experts, in contrast, say breaking up today's vast ranges into smaller habitats could promote the evolution of new species. That's because populations of the same type of organism that are separated from each other may diverge over time. As populations are reduced in size, genetic changes may accumulate more rapidly. Another reason diversity may rebound -- as it normally does after a major extinction episode -- is that disturbances caused by human beings do not eliminate habitats, but merely change them.


Story Source:

The above story is based on materials provided by University Of Texas, Austin. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas, Austin. "Extinction Rate Across The Globe Reaches Historical Proportions." ScienceDaily. ScienceDaily, 10 January 2002. <www.sciencedaily.com/releases/2002/01/020109074801.htm>.
University Of Texas, Austin. (2002, January 10). Extinction Rate Across The Globe Reaches Historical Proportions. ScienceDaily. Retrieved March 30, 2015 from www.sciencedaily.com/releases/2002/01/020109074801.htm
University Of Texas, Austin. "Extinction Rate Across The Globe Reaches Historical Proportions." ScienceDaily. www.sciencedaily.com/releases/2002/01/020109074801.htm (accessed March 30, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, March 30, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Arthropod Fossil Might Be Relative Of Spiders, Scorpions

New Arthropod Fossil Might Be Relative Of Spiders, Scorpions

Newsy (Mar. 29, 2015) A 508-million-year-old arthropod that swam in the Cambrian seas is thought to share a common ancestor with spiders and scorpions. Video provided by Newsy
Powered by NewsLook.com
Vietnam Rice Boom Piles Pressure on Farmers and the Environment

Vietnam Rice Boom Piles Pressure on Farmers and the Environment

AFP (Mar. 29, 2015) Vietnam&apos;s drive to become the world&apos;s leading rice exporter is pushing farmers in the fertile Mekong Delta to the brink, say experts, with mounting costs to the environment. Duration: 02:35 Video provided by AFP
Powered by NewsLook.com
Raw: Lioness Has Rare Five-Cub Litter

Raw: Lioness Has Rare Five-Cub Litter

AP (Mar. 27, 2015) A lioness in Pakistan has given birth to five cubs, twice the usual size of a litter. Queen gave birth to two other cubs just nine months ago. (March 27) Video provided by AP
Powered by NewsLook.com
Jockey Motion Tracking Reveals Racing Prowess

Jockey Motion Tracking Reveals Racing Prowess

Reuters - Innovations Video Online (Mar. 26, 2015) Using motion tracking technology, researchers from the Royal Veterinary College (RVC) are trying to establish an optimum horse riding style to train junior jockeys, as well as enhance safety, health and well-being of both racehorses and jockeys. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins