Dogs May Date Back 60,000 to 100,000 Years to
Hunter-Gatherer Societies, UCLA Scientists, Colleagues Find
Dogs have ancient origins dating back perhaps 100,000 years or more
-- much older than scientists had thought -- UCLA scientists and colleagues found.
While many scientists believed, based on archaeological records,
that domestic dogs dated back only 14,000 years, molecular genetic techniques reported in
the June 13 [1997] issue of the journal Science show that man's best friend is much older.
The new research also confirms that dogs evolved from wolves.
"Our data show that the origin of dogs seems to be much more
ancient than indicated in the archaeological record," said Robert K. Wayne, UCLA
associate professor of biology. "The origin of dogs dates well before the development
of agricultural population centers that occurred approximately 10,000 to 14,000 years ago,
and goes back to hunter-gatherer societies. While many people think a high level of
sophistication was required to domesticate wild mammals, our data imply that very
primitive societies may have had domestic animals."
Scientists believe from archaeological records that many domestic
animals, including cats and cattle, originated within the last 14,000 years. Cats may have
been domesticated as recently as 7,000 years ago, Wayne said.
Wayne noted that his techniques do not enable exact dates to be
determined for dogs. "Because of the extrapolation involved in the calculations, it's
possible that the first dog dates back 60,000 years, or perhaps more than 100,000
years," he said.
"It is possible that the first dog
dates back 60,000,
or perhaps more than 100,000 years...."
For the research, Wayne and his colleagues studied DNA sequences
from 140 dogs representing 67 breeds -- including golden retrievers, German shepherds,
collies, St. Bernards, poodles, bulldogs, Irish setters, rottweilers, English sheepdogs,
fox terriers and chow chows. They also analyzed 162 wolves from the United States, Canada,
Mexico, Russia, China, India, Italy, Portugal, Spain, France, Sweden, Saudi Arabia, Israel
and other countries, as well as jackals and coyotes.
The scientists analyzed DNA sequences from the control region of the
mitochondrial genome -- a region with a high mutation rate. They were surprised by the
great diversity of DNA sequences they found within dogs.
"We expected to find DNA sequences in dogs that were closely
related to those in wolves, perhaps even indistinguishable from those in wolves,"
Wayne said. "We expected to find a few different sequences in dogs; instead, we found
26.
"We initially suspected the amount of genetic
diversity in the marker we analyzed would be very low because the only way that diversity
accumulates is through DNA mutations over time, and 14,000 years is not enough time for
many mutations to appear.
"We have found that the origin of dogs is much older than
previously believed because the genetic diversity within dogs is much greater than one
would find if their origin were as recent as 14,000 years ago," Wayne added.
"Given the amount of genetic diversity that we found, we can calculate how long it
should have taken to achieve this diversity if mutations alone were driving the process.
Our calculations suggest the first domestic dog might be as old as 100,000 years or
older."
While some scientists thought that dogs evolved from jackals or
coyotes, Wayne and his colleagues found no evidence to support that view.
SOURCE:
News release [no longer online]:
http://www.uclanews.ucla.edu/Docs/SWHL269.html
Date: June 10, 1997 | Contact: Stuart Wolpert, UCLA
E-mail: stuartw@college.ucla.edu |
Telephone: 310-206-0511
Science article: http://www.idir.net/~wolf2dog/wayne1.htm
ORDER THIS BOOK: Dogs: A
Startling New Understanding of Canine Origin, Behavior &
Evolution by Raymond & Lorna Coppinger
READ: A Review of Ray & Lorna
Coppinger's "Dogs: A Startling New Understanding of
Canine Origins, Behavior & Evolution" by Barbara Bradley Petura,
WorkingDogWeb.com webmaster
READ: An Interview with Ray
& Lorna Coppinger with Barbara Bradley Petura, WorkingDogWeb.com
webmaster
READ: Humans Brought Domesticated
Dogs to New World More Than 12,000 Years Ago, Researchers Report and Dogs Evolved in
Asia, an article by Barbara Bradley Petura, WorkingDogWeb.com webmaster
LINKS: Click for original journal articles:
· The Multiple and
Ancient Origins of the Domestic Dog
· Molecular Evolution of
the Dog Family
CLICK ABOVE to browse our dog bookstore - thanks!
