Subscribe free to our newsletters via your
. Earth Science News .




FLORA AND FAUNA
Bird tree tells new tale of evolution
by Staff Writers
Burnaby, Canada (SPX) Nov 02, 2012


illustration only

Using the world's first family tree linking every known bird species, scientists, including two at Simon Fraser University, have discovered that birds appear to be accelerating their rate of evolution. The finding is contrary to the scientists' expectations.

They spent five years creating their tree, using millions of years worth of fossil data stretching back to the Age of the Dinosaurs, DNA data and supercomputers. They then mapped where on Earth and when in history birds' diversification took place.

A new paper in the journal Nature contains the scientists' profile of how 9,993 bird species currently alive globally made it to where they are today. Based on previous studies, the researchers expected to see bird speciation slowing down through time.

But SFU biologist Arne Mooers, Jeff Joy, a postdoctoral fellow in his lab, and researchers at Yale University, University of Sheffield and University of Tasmania have discovered birds' speciation rate is increasing, not declining.

"Perhaps birds are special," theorizes Mooers. "Maybe they're so good at getting around they can escape local competition from relatives and start anew elsewhere, producing bursts of new species at different times and in different parts of the globe."

The authors have also discovered that birds' speciation rate doesn't drop off the further they are from the equator. Since three quarters of all birds are found near the equator, it was expected that speciation there would be more common.

"We know the tropical biome has been shrinking during the last 15 million years," says Joy. "Perhaps, just as bushtits bunch together closely at night, bird species have clustered together in the tropics as their habitat shrunk."

"We need to think a lot more about how Earth's changing climate has led to current distributions," says Mooers. "It's a lovely conundrum."

Unfortunately, birds' rosy speciation history doesn't nullify the fact that they can't outfly their growing human-induced rate of extinction. Researchers estimate that birds have recently been proliferating at a rate of about one new bird species every 700 years. Meanwhile, they estimate birds' recent human-caused extinction rate to be about 300 times higher.

.


Related Links
Simon Fraser University
Darwin Today At TerraDaily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








FLORA AND FAUNA
New study to examine ecological tipping points in hopes of preventing them
Santa Barbara CA (SPX) Nov 01, 2012
Predation by otters keeps urchin populations in check, allowing kelp - a favorite food of urchins - to flourish. But what if otters were harvested to near extinction for their fur? The resulting overabundance of urchins would decimate the kelp forest, leaving little food or shelter for fish and invertebrates. And so it may go, as declines in these species are likely to affect others. Such ... read more


FLORA AND FAUNA
In 'forgotten' New York borough, storm anger boils

Post-Sandy, New York commuters resort to ferries

New Yorkers get by with help from friends

New Jersey town rediscovers old ways post-Sandy

FLORA AND FAUNA
Android smartphone shipments boom: industry tracker

Samsung sells 3 mn Galaxy Note II smartphones since debut

Apple iPad mini makes low key debut

Spaceflight Completes Secondary Payload System Preliminary Design Review With Hardware Fabrication Underway

FLORA AND FAUNA
Why Seas Are Rising Ahead of Predictions

Mekong hydropower project gets a boost

Ocean Salinity Trends Show Human Fingerprint

Asia's fishermen caught in escalating sea tensions

FLORA AND FAUNA
Antarctic ocean sanctuary talks end in failure

Two Perfect Days for IceBridge

Polar bears seen taking refuge on icebergs

Biologists record increasing amounts of plastic litter in the Arctic deep sea

FLORA AND FAUNA
Could chloroplast breakthrough unlock key to controlling fruit ripening in crops?

Study details essential role of trust in agricultural biotech partnerships

FAO: Africa land grabs like 'Wild West'

NASA Maps How Nutrients Affect Plant Productivity

FLORA AND FAUNA
Evacuees return home after Indian cyclone

Sandy's wrath lingers in battered US northeast

For New York rats, a question of sink or swim

Tabletop fault model reveals why some quakes result in faster shaking

FLORA AND FAUNA
Nigeria military kills about 40 in northeast: residents

Lesotho fears cash shortfall as food crisis deepens

Senegal foreign, interior ministers lose jobs in reshuffle

G.Bissau's alleged coup mastermind to face military court

FLORA AND FAUNA
Bigger human genome pool uncovers more rare variants

Village in Bulgaria said Europe's oldest

Genetics suggest global human expansion

'Digital eternity' beckons as death goes high-tech




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement