Environmental News Network
February 19, 2007 — By Alister Doyle, Reuters
OSLO -- Genetic tests of North American birds show what may be 15 new species including ravens and owls -- look alikes that do not interbreed and have wrongly had the same name for centuries, scientists said on Sunday.
If the findings from a study of birds' DNA genetic "barcodes" in the United States and Canada hold true around the world, there might be more than 1,000 new species of birds on top of 10,000 identified so far, they said.
A parallel study of South American bats in Guyana also showed six new species among 87 surveyed, hinting that human studies of the defining characteristics of species may have been too superficial to tell almost identical types apart.
"This is the leading tip of a process that will see the genetic registration of life on the planet," said Paul Hebert of the Biodiversity Institute of Ontario, a co-author of the report in the British Journal Molecular Ecology Notes.
"You can't protect biodiversity if you can't recognise it."
The scientists found 15 potential new species among 643 types of bird studied from the Arctic to Florida. The sample covers almost all 690 known breeding species in North America.
"North American birds are among the best studied in the world," said co-author Mark Stoeckle of the Rockefeller University in New York. "Even in a group where people have been looking very carefully there are genetically different forms that appear to be new species."
CURVE BILLED THRASHER
Look alike species were of the Northern Fulmar, Solitary Sandpiper, Western Screech Owl, Warbling Vireo, Mexican Jay, Western Scrub-Jay, Common Raven, Mountain Chickadee, Bushtit, Winter Wren, Marsh Wren, Bewick's Wren, Hermit Thrush, Curve Billed Thrasher and Eastern Meadowlark.
"It would be a reasonable guess that there are likely to be at least 1,000 genetically distinct forms of birds (worldwide) that will be recognised as new species," Stoeckle said.
The genetic tests, for instance of a feather, give a readout of a "barcode" for each creature similar to the black and white parallel lines on packages at supermarkets.
They said DNA diverged by at least 2.5 percent -- enough, they said, to define a species despite almost identical shape, plumage and song. A one percent difference typically indicated a million years without interbreeding, they said.
The study also found 14 pairs of birds with separate identities that were almost genetic "twins", two trios of birds were DNA triplets and eight gull species were almost identical.
"Some of these on close inspection may really be better considered as a single species," said Stoeckle. "Others are probably very young species at the borderline."
The Snow Goose and Ross's Goose, for instance, shared 99.8 percent of DNA and the black-billed magpie and the yellow-billed magpie 99.6 percent. Gulls such as the Glaucous and Iceland Gulls were 99.8 percent the same.
The scientists said there was no clear scientific definition of a species -- inability to interbreed was often favoured.
"But that's difficult -- we're not watching bats mate in caves, we're not often watching small life forms," Hebert said.
The scientists are hoping to raise $100 million to compile a barcode of life -- 10 million DNA records of 500,000 animal species by 2014.