OTAGO, New Zealand, Oct. 4 (UPI) -- A rare seabird scientists had believed to be extinct has been declared alive and well by New Zealand researchers who conducted DNA studies.
Scientists at the University of Otago compared ancient and modern DNA and confirmed the New Zealand storm petrel is still flying in the skies over the island nation, China's official Xinhua news agency reported.
The discovery that the species lives on justifies establishing a program to try to restore the bird's numbers, Otago zoologist Bruce Robertson said.
The researchers began taking blood samples after the first bird thought to be the extinct storm petrel flew into the wheelhouse of a fishing vessel off the east coast of New Zealand in 2003.
They compared DNA with that from three 150-year-old skins of the New Zealand storm petrel collected in the 1800s and held by museums in England and France.
"We found they were one and the same, and these birds are a distinct species of storm petrel," Robertson said in a report published last week.
Read more: http://www.upi.com/Science_News/2011/10/04/Seabird-thought-extinct-is-alive-and-well/UPI-32221317774190/#ixzz1a6OaPa5x
Showing posts with label dna study. Show all posts
Showing posts with label dna study. Show all posts
Friday, October 7, 2011
Sunday, July 10, 2011
Polar bears traced back to Britain
All polar bears originate from a single ancestor which lived in Britain or Ireland about 50,000 years ago, according to DNA study by scientists. New evidence from fossils found in Irish caves shows that modern polar bars evolved from a single female brown bear at the peak of the last ice age.
Despite the significant differences between polar bears, which are expert swimmers, and brown bears, which are better climbers, the species have often come into contact over the past 100,000 years during periods of unusually hot or cold weather.
A genetic marker carried by every polar bear alive today proves that they all descend from the same female brown bear, who bred with a polar bear to create hybrid offspring.
It had been assumed that this took place in Alaska 14,000 years ago, but now analysis of 242 brown bear and polar bear DNA samples from the past 120,000 years show the hybridisation of the two species occurred much earlier.
Fossils found in Irish caves show that polar bears in fact began carrying the DNA of the female brown bear between 20,000 and 50,000 years ago, before brown bears disappeared from the British Isles.
The study, led by Dr Beth Shapiro of Penn State University in the USA and Prof Daniel Bradley of Trinity College Dublin, was published in the journal Current Biology.
Dr Shapiro said: “Previous research has indicated that the brown bear contributed genetic material to the polar bear's mitochondrial lineage – the DNA that is passed exclusively from mothers to offspring.
“But, until now, it was unclear just when modern polar bears acquired their mitochondrial genome in its present form."
By Nick Collins, Science Correspondent
http://www.telegraph.co.uk/earth/wildlife/8622987/Polar-bears-traced-back-to-Britain.html
Despite the significant differences between polar bears, which are expert swimmers, and brown bears, which are better climbers, the species have often come into contact over the past 100,000 years during periods of unusually hot or cold weather.
A genetic marker carried by every polar bear alive today proves that they all descend from the same female brown bear, who bred with a polar bear to create hybrid offspring.
It had been assumed that this took place in Alaska 14,000 years ago, but now analysis of 242 brown bear and polar bear DNA samples from the past 120,000 years show the hybridisation of the two species occurred much earlier.
Fossils found in Irish caves show that polar bears in fact began carrying the DNA of the female brown bear between 20,000 and 50,000 years ago, before brown bears disappeared from the British Isles.
The study, led by Dr Beth Shapiro of Penn State University in the USA and Prof Daniel Bradley of Trinity College Dublin, was published in the journal Current Biology.
Dr Shapiro said: “Previous research has indicated that the brown bear contributed genetic material to the polar bear's mitochondrial lineage – the DNA that is passed exclusively from mothers to offspring.
“But, until now, it was unclear just when modern polar bears acquired their mitochondrial genome in its present form."
By Nick Collins, Science Correspondent
http://www.telegraph.co.uk/earth/wildlife/8622987/Polar-bears-traced-back-to-Britain.html
Subscribe to:
Posts (Atom)