A new study adds to the evidence that dogs were domesticated before first migrating to the Americas. The dogs’ history parallels that of ancient humans who migrated from North Asia to North America, dispersed throughout the Americas and suffered major population declines upon contact with European colonists. Dots represent sites from which the bones of ancient dogs were collected for the new analysis and the relative ages of the bones.
Ancient dog burials like this one found at the Janey B. Goode site near Brooklyn, Illinois, provided genetic material for a new study of dogs in the Americas.
CHAMPAIGN, Ill. — A study reported in the journal Science offers an enhanced view of the origins and ultimate fate of the first dogs in the Americas. The dogs were not domesticated North American wolves, as some have speculated, but likely followed their human counterparts over a land bridge that once connected North Asia and the Americas, the study found.
This is the first comprehensive genomic study of ancient dogs in the Americas to analyze nuclear DNA, which is inherited from both parents, along with mitochondrial DNA, which is passed down only from mothers to their offspring. By comparing genomic signatures from 71 mitochondrial and seven nuclear genomes of ancient North American and Siberian dogs spanning a period of 9,000 years, the research team was able to gain a clearer picture of the history of the first canine inhabitants of the Americas.
A ritual burial of two dogs at a site in Illinois near St. Louis suggests a special relationship between humans and dogs at this location and time (660 to 1350 years ago).
The oldest dog remains in the Americas date to about 9,000 years ago, many thousands of years after people began migrating over a land bridge connecting present-day Siberia and Alaska. The ancient dogs analyzed in the new study likely originated in Siberia, the researchers found. The dogs dispersed to every part of the Americas, migrating with their human counterparts.
As a graduate student at the U. of I., Kelsey Witt led the mitochondrial DNA genome work on a newly published study of ancient dogs. Witt is now a postdoctoral researcher at the University of California, Merced.
These dogs persisted for thousands of years in the Americas, but almost completely vanished after European contact, the researchers found.
“This suggests something catastrophic must have happened, and it’s likely associated with European colonization,” said senior lead author Laurent Frantz, a lecturer at Queen Mary University and co-investigator at the University of Oxford. “But we just do not have the evidence to explain this sudden disappearance yet.”
“By looking at genomic data along with mitochondrial data, we were able to confirm that dogs came to the Americas with humans, and that nearly all of that diversity was lost – most likely as a result of European colonization,” said Kelsey Witt, who led the mitochondrial DNA genome work as a graduate student in the laboratory of University of Illinois anthropology professor Ripan Malhi, who also is an author of the study.
“Few modern dogs have any trace of these ancient lineages,” said Witt, now a postdoctoral researcher at the University of California, Merced.
Anthropology professor Ripan Malhi works with teams that include Indigenous scientists and scholars on DNA studies that offer insights into the ancient history of the Americas.
The team also discovered that the genomic signature of a transmissible cancer that afflicts dogs appears to be one of the last “living” remnants of the genetic heritage of dogs that populated the Americas prior to European contact.
The new findings reinforce the idea that early human and dog inhabitants of the Americas faced many of the same challenges after European contact, Malhi said.
“It is known how Indigenous peoples of the Americas suffered from the genocidal practices of European colonists after contact,” he said. “What we found is that the dogs of Indigenous peoples experienced an even more devastating history and a near-total loss, possibly as a result of forced cultural changes and disease.”
The paper “The evolutionary history of dogs in the Americas” is available online and from the U. of I. News Bureau.
When trees grow into electrical lines, they can create safety hazards and disrupt service. During high winds, strong thunderstorms or snow or ice storms, limbs and even whole trees can fall on electric lines, tearing down energized lines and equipment. Broken limbs can cause outages just by making contact with electric lines and equipment. The water, sap and chemicals in trees are excellent electricity conductors. If a tree has grown into a power line, electricity can travel through the tree to the ground and create an electrocution hazard. Trees touching power lines can also cause fires.
Jackson EMC maintains the area around the lines, known as the right-of-way, to keep members and employees safe.
These men wield chainsaws, keeping vegetation at bay, clearing the path for your power. During storms they ride the lines, looking for fallen trees that need to be cleared, declaring areas safe for passage by linemen looking to restore power. Right-ofway crews work year-round to remove threats to your power supply and to keep workers safe from potential danger.
Here are the facts about the program from men charged with managing the 6,552 miles of overhead wire powering the homes and businesses of Jackson EMC's members.
A lot of people don’t understand the voltage on the line and how dangerous it is. We are doing this for safety; for our safety, and theirs. Plus, if we can take the time now to clear it, you won’t have to wait for us to make a path after a storm. – Benton
Never attempt to trim or remove a tree that has power lines running through it. If you discover trees growing into lines, please call your local Jackson EMC office to report it. – Mize
I own property too. We don’t want to tear up your property, just like we don’t want ours messed up. – Pressley
Crews work year-round, Monday to Thursday from 6:30 a.m. to 5 p.m. We have a lot of miles, so we have to clear all year long. – Roberson
One crew can clear three miles a month. In all, our crews clear 1,200 miles each year. We can reach each mile of line about every five to six years. – Benton
Jackson EMC has five supervisors who oversee 32 independent, tree-trimming contractor crews that maintain its right-of-way. The contractors work 40 hours a week and are professionals in the field of utility arboriculture and use proven industry-standard pruning techniques, proper tools and safety practices.
All contractor crews are supervised by Jackson EMC personnel. When trees are being trimmed, Jackson EMC’s supervisors will be in the area, and a notice that the contractor is working for Jackson EMC will be posted on all contractor vehicles. – Mize
Great care is taken to ensure limbs that must be cut from trees are done to protect the tree and keep it growing safely away from lines. – Benton
Jackson EMC uses directional trimming to maintain clearances between trees and power lines. Directional trimming is recommended by the International Society of Arboriculture, American National Standards Institute and the National Arbor Day Foundation. – Mize
We only cut what we have to, which is a clearance of 15 feet in each direction of the line: left, right and under. – Benton
Trees are trimmed, underbrush is mowed down and trees growing too tall under the lines are taken down or scaled back. – Waters
We consider several factors when pruning a tree for line clearance, in priority order: public and right-of-way worker safety, service reliability, correct arboriculture pruning techniques, and finally, aesthetics. – Mize
We make an effort to reach each member whose power lines will be cleared. If we don’t meet you at your door, a brochure about the program with contact information is left behind. – Benton
I knock on their doors and let them know. I like to talk to them. They will tell you where risks are on their property – like where the septic tank is buried. – Pressley
Gratification of doing the job. It is a very rewarding career, keeping the lights on for people. I like to hear them say ‘my lights never go out.’ – Waters
I enjoy coming to work every day; working with the crews, and I have a good boss. I like talking with customers and hearing about the history of the lines. – Benton
The Colorado County Circus of Health and Safety Day was held July 25 from 9:00 a.m. to 11:00 a.m. at Columbus Elementary School in Columbus, Texas (105 Cardinal Lane). I was happy to collaborate with a great group to help organize the 2015 event, including the AgriLife County Extension Agent, Columbus County Hospital and the Columbus Department of Health and Human Services. The health and safety day was a perfect example of community collaboration and local partnerships meeting the needs of our residents.
More than 220 children and 110 adults participated in the countywide event. Each child received a backpack filled with supplies for school. They also received timely health and safety information from a variety of organizations present on the day of the event. The planning team was overjoyed with raising nearly $3, 225, which helped purchase the backpacks and supplies for the children.
Families had the opportunity to view seatbelt safety demonstrations and receive car seat checks provided by the Columbus Community Hospital Nurses. At the Methodist Healthcare Ministries' booth, I shared information about nutrition, the importance of physical activity and hygiene. The Columbus EMS, fire department and police department had popular outdoor booths. A representative from the Lower Colorado River Authority was onsite to share all-terrain vehicle safety tips. Snow cones and water were also provided to help everyone cool down outdoors.
One of the highlights of the morning was the visit by the Life Flight helicopter. The helicopter surprised everyone when it landed in the school's playing field. The children really enjoyed the opportunity to see inside the aircraft. It was a great educational tool and fun opportunity for all!
The 2015 health and safety day proved to be a successful event. I was thankful to be involved because I know the event helped lessen the financial burden on parents as they prepare their children for a new school year. Knowing the event helps so many makes me extremely proud of our outreach within the community.