Dog may sense sounds beyond human perception

Dr. Michael Fox

Question: We have a lovely little 8-year-old Shih Tzu we adopted 7 years ago from a shelter. She seems to know her bedtime, so she retires to the laundry room, on her own, to spend the night on her pillow at 9 p.m. However, she has developed one unusual habit: Before she falls asleep, she scratches on the dryer door vigorously with her front right paw, then the left. (We are not worried about the dryer.) She continues this for about 10 to 15 minutes. Sometimes she will stop, then start again for a few more minutes. We take her for walks twice a day, about one mile each time. She lets us know when she wants to go out in the backyard. She is in good health.

What do you think of this? — P.S., Silver Spring, Maryland

Dear P.S.: Your dog’s ritual-like behavior may have started as a comfort-seeking activity that provides some release of anxiety before sleeping.

Dogs will instinctively turn and repeatedly paw around and around to make their lying area comfortable and clear of possibly injurious objects.

My guess is that the dryer door-pawing behavior was triggered by sounds that the machine made, possibly at a high frequency that you could not hear, that upset your dog. Many devices produce such sounds, even when not operating but still plugged in.

Confirming the origin of the domestic cat

My assertion over 40 years ago in my book “Understanding Your Cat” — that all our house cats, with the obvious exception of recent wildcat hybrids, are descendants of the North African desert cat, Felis lybica — has been recently confirmed and refined.

An international team of scientists recently published their analysis of DNA from cats that lived between 8000 B.C. and the 20th century in the Near East, Africa and Europe in the journal Nature Ecology and Evolution (2017).

Their findings indicate that the first descendants of the now renamed

Felis silvestris lybica, a regional subspecies of wildcat, came from two distinct wildcat populations.

The first evolved in the Middle East and spread to Europe as early as 4400 B.C. A separate lineage of the domestic cat came out of Egypt, spreading to the Middle East and Europe from the fifth century on. Sedentary agrarian communities welcomed them as natural rodent controllers and crop/ harvest protectors.