So the research suggests that in the early evolution of vertebrates, one key to survival was the recognition of the presence of other animals that could be harmful, or could be harvested. That ability was honed to perfection in the part of the early brain that was responsible for reacting to changes in the environment, including the sudden appearance of other critters, "both aversive and cute," the study notes.
As evolution continued on its long, gradual course, the amygdala remained important even to this day, because it's still useful to know if that fuzzy animal down the road is a dog or a wolf.
But it's still surprising that the intensity of the brain activity would be no greater for a wolf than a dog, long regarded as man's best friend. So which emotion is the strongest, the urgent need to avoid the wolf, or the friendly urge to pet the dog?
A recent event in my hometown of Juneau, Alaska, might shed a little light on that. A couple of weeks ago, a young woman found her 15 minutes of fame when the local newspaper disclosed that she had punched a bear in the nose to keep it from killing her dog.
Apparently, compassion for her pet outweighed her fear of the bear, which backed away and quietly retreated into a nearby forest.
So perhaps what it boils down to is her amygdala recognized the presence of two animals, one loved, the other feared. In this case, love trumped fear. Or perhaps her fear for her dog was greater than her fear of the bear.
By the way, both woman and dog are doing fine. Condition of bear's nose unknown. And hitting a bear to save a dog is not recommended by wildlife experts.