Dogs are loyal, playful, loving and sometimes cute as a button. It's no wonder we love them.
Dogs were likely one of the very first animals we humans domesticated. They've been sitting around our campfires for a very long time. We train them to sit, shake and lie down. It also could be said that they train us to dispense kibbles, rawhide treats and scratches behind the ears.
What matters isn't which side comes out ahead in the exchange, I like to think, but that both sides benefit from our association.
Recently I had occasion to read aloud a news report to Buster Brown, my Labrador retriever mix who came from the dog pound.
The story originated in Germany, where a study was done with dogs that have been trained to indicate when they smell chemicals emitted by cancer cells in the human body.
This isn't the first such study to be done, but it confirmed what earlier ones had shown: dogs can be good early warning detectors of malignancies within us people.
The study used two German shepherds (naturally), an Australian shepherd and one Labrador retriever. The dogs were trained to lie down when they smelled lung cancer.
The dogs were just house-dogs, and the training didn't go much beyond that used in typical puppy school. So it's likely that what the four dogs could do, so could my Buster and your Fido, too.
The canines in the study were given test tubes containing people's breath samples, both healthy subjects and those who had lung cancer. The dogs had been trained to lie down when they smelled traces of lung cancer and touch the vials with their noses. About 70 percent of the time, the dogs successfully identified patients known to have lung cancer.
Similar studies have tested dogs' abilities to detect breast cancer, colon cancer, skin cancer and more. Some studies have had much higher detection rates than 70 percent, too.
Clearly dogs can tumble to just a tiny trace of chemicals associated with cancer cells. Dogs have more neurons running from the nose to the brain than we people do, and a larger proportion of the dog brain is devoted to processing information from the nose than is the case in our human noggins.
That dogs can smell malignancies would seem to indicate the cancers create particular chemicals that are otherwise not in our bodies.
Exactly what those compounds are remains a mystery. In other words, we can say the dogs in Germany did pretty well at detecting lung cancer, but we don't know what specific chemicals in the test tube vials the dogs responded to. And, of course, the dogs can't tell us that part of the story.
It's interesting to speculate why it took us so long to ask Fido's help in cancer detection. I think it's partly because of the way we view science and all things medical.
We think that the best scientific or medical devices will be large and expensive machines. Likely they'll be scary, too, at least if you have to spend time with one as a patient.
It's just outside our framework of thinking to imagine that the mutt under the kitchen table at home could do as well as a chemical detector designed by an engineer and costing tens or hundreds of thousands of dollars.
As a friend of mine in graduate school used to say, "Scientific instruments should be big, noisy, scary and cold."
E. Kirsten Peters, Ph.D., is a rural Northwest native whose column is a service Washington State University. Follow her at rockdoc.wsu.edu and on Twitter @RockDocWSU.