Sunday, September 21, 2014
YOLO COUNTY NEWS
99 CENTS

Dogs’ tale: Study shows they trailed ancient farmers

Australian dingoes like this one figured into a UC Davis study of the origins of the modern Western dog. Researchers calibrated the timing of ancient dogs' movement by figuring out the rate at which genetic markers on the Y chromosome mutated in dingoes. Rob Davis/Kimberley Land Council

By
From page A15 | February 24, 2013 |

Part of the ancient mystery of the makeup of the modern Western dog has been solved by a team led by researchers at the UC Davis School of Veterinary Medicine.

Several thousand years after dogs originated in the Middle East and Europe, some of them moved south with ancient farmers, distancing themselves from native wolf populations and developing a distinct genetic profile that is now reflected in today’s canines.

These findings, based on the rate of genetic marker mutations in the dog’s Y chromosome, supply the missing piece to the puzzle of when ancient dogs expanded from Southeast Asia. The study results are published online this month in the journal Molecular Biology and Evolution.

“Our findings reconcile more than a decade of apparently contradictory archaeological and genetic findings on the geographic origins of the dogs,” said Ben Sacks, lead study author and director of the canid diversity and conservation group in UCD’s veterinary genetics laboratory.

Considerable archaeological evidence indicates that the first dogs appeared about 14,000 years ago in Europe and the Middle East, while dogs did not appear in Southeast Asia until about 7,000 years later. Scientists have been puzzled, though, because growing genetic evidence suggests that modern Western dogs, including modern European dogs, are derived from a Southeast Asian population of dogs that spread throughout the world.

The problem: If dogs originated in Europe, why does genetic evidence suggest that modern European dogs are originally from Southeast Asia?

Sacks and his team think they’ve found the answer.

“Data from our study indicate that about 6,000 to 9,000 years ago, during what is known as the Neolithic age, ancient farmers brought dogs south of the Yangtze River, which runs west to east across what is now China,” Sacks said.

“While dogs in other parts of Eurasia continued to readily interbreed with wolves, the dogs that moved into Southeast Asia no longer lived near wolves, and so they developed a totally different evolutionary trajectory, influenced by the agriculture of Southeast Asia,” he said. “Those ancient dogs apparently underwent a significant evolutionary transformation in southern China that enabled them to demographically dominate and largely replace earlier western forms.”

To calculate when the modern European and Southeast Asian dogs diverged, the researchers calculated the mutation rate of genetic markers on the Y chromosome in a sample of 100 Australian dingoes, a dog population known to have appeared about 4,200 years ago. Knowing the rate at which these genetic mutations occur, the researchers were able to backtrack through history and estimate the point when dogs of Eurasia and Southeast Asia parted company as being roughly 7,000 years ago.

“So, in a sense, both of the original hypotheses are true: Dogs did originate in Europe and the Middle East, but modern dogs trace their ancestry most recently to the East and specifically Southeast Asia,” Sacks said.

He noted that a study, led by evolutionary geneticist Erik Axelsson from Uppsala University in Sweden and published in the January issue of the journal Nature, suggests a distinction between dogs and wolves can be seen in their ability to digest starch, strongly suggesting an evolutionary adaptation to human farmers.

“Both studies fit together nicely, although our research teams differ on when we suspect modern dogs developed the ability to digest starch,” Sacks said. “The other group suggested that diet-related change happened at the outset of dog origins, at which time humans were still hunter-gatherers.”

“In contrast, we hypothesize that the starch adaptation occurred much later in Southeast Asia, once agriculture — rice farming in this case — had become the major mode of subsistence for humans,” he said.

Sacks said that the study also shines light on the origin of dingoes, the wild dogs of Australia.

Data from the study suggest that New Guinea singing dogs and Australian dingoes reflect a dispersal of dogs, possibly from Taiwan, that was independent of the movement of dogs throughout the islands of Southeast Asia. The island dogs appear to have originated in mainland Southeast Asia, rather than Taiwan, he said.

The possibility of Taiwan being the origin of an independent migration for these dogs Down Under is intriguing but will require further research to confirm, Sacks said.

Other UCD researchers on this study were Sarah Brown and Niels Pedersen.

— UC Davis News Service

Comments

comments

.

News

Bet Haverim hosts High Holy Day services

By Special to The Enterprise | From Page: A1

 
Elementary school counselors: necessary, but poorly funded

By Anne Ternus-Bellamy | From Page: A1 | Gallery

 
Teams assess damage as wildfire burns

By The Associated Press | From Page: A2 | Gallery

 
Driver arrested for DUI after Saturday morning crash

By Enterprise staff | From Page: A2

 
Davis Community Meals needs cooks

By Enterprise staff | From Page: A3

 
Help raise funds for juvenile diabetes cure

By Enterprise staff | From Page: A3

 
Jewelry, art for sale at Senior Center

By Enterprise staff | From Page: A3

Da Vinci awarded $38,000 for restorative justice program

By Anne Ternus-Bellamy | From Page: A4

 
Hawk Hill trip planned Sept. 30

By Enterprise staff | From Page: A4

UC campus chancellors granted hefty pay raises

By The Associated Press | From Page: A4

 
Send kids to camp!

By Enterprise staff | From Page: A4

Outdoor yoga marathon celebrates community

By Special to The Enterprise | From Page: A5

 
Wise words

By Sue Cockrell | From Page: A12

 
.

Forum

Awareness is key to this fight

By Creators Syndicate | From Page: B5

 
We’re living in the Golden State of emergency

By Debra DeAngelo | From Page: A6

Options for protection come with flu season

By The Associated Press | From Page: A6

 
Are we there yet? Not enough hours in the day to goof off

By Tanya Perez | From Page: A6Comments are off for this post

It’s time for Davis Scouts to stand up for what is right

By Special to The Enterprise | From Page: A10

 
Mike Keefe cartoon

By Debbie Davis | From Page: A10

Building something at schools’ HQ

By Our View | From Page: A10

 
Don’t sell city greenbelt

By Letters to the Editor | From Page: A10

Paso Fino project is flawed

By Letters to the Editor | From Page: A10

 
Paso Fino — it’s not worth it

By Letters to the Editor | From Page: A10

Archer will get my vote

By Letters to the Editor | From Page: A10

 
Maybe David can beat Goliath again

By Lynne Nittler | From Page: A11 | Gallery

Speak out

By Enterprise staff | From Page: A11

 
.

Sports

DHS gets on its Morse to beat Edison

By Thomas Oide | From Page: B1 | Gallery

 
JV Blue Devils drop low-scoring affair

By Spencer Ault | From Page: B2

 
Republic FC’s fairy tale season continues

By Evan Ream | From Page: B3 | Gallery

Wire briefs: Giants rally falls short in San Diego

By The Associated Press | From Page: B3

 
Four local swimmers qualify for Olympic Trials

By Enterprise staff | From Page: B3

‘We’re a way better team’ than record, says UCD’s Shaffer

By Bruce Gallaudet | From Page: B4 | Gallery

 
UCD roundup: Aggie men pound Pomona-Pitzer in the pool

By Enterprise staff | From Page: B4

Davis 15-year-old making a splash in European F4 series

By Bruce Gallaudet | From Page: B8 | Gallery

 
.

Features

.

Arts

‘Ladies Foursome’ adds shows

By Enterprise staff | From Page: A3

 
.

Business

UCD grad’s startup earns kudos at TechCrunch event

By Special to The Enterprise | From Page: A7

 
Styles on target for November debut

By Wendy Weitzel | From Page: A7

MBI hires VP of marketing

By Enterprise staff | From Page: A7

 
Taylor Morrison unveils new Woodland community next weekend

By Special to The Enterprise | From Page: A9 | Gallery

Rob White: What is an ‘innovation center’?

By Rob White | From Page: A9

 
.

Obituaries

Carol L. Walsh

By Special to The Enterprise | From Page: A4

 
.

Comics

Comics: Sunday, September 21, 2014

By Creator | From Page: B8