In his book, The Mind of the Raven, Bernd Heinrich relates on page 193 an incident involving a woman who lived with her husband in a cabin near the head of Boulder Canyon. The woman was outside when she noticed a raven flying nearby. "I never paid much attention to ravens," she said, "but this one was so noisy that it was downright irritating." The raven came closer, made a pass near her and then flew up to some rocks where she saw a crouching mountain lion. Just then her 300 pound husband came out of the cabin and the lion slipped away.
The woman, who was very religious, thought it was a miracle. "That raven saved my life," she said. Maybe so, but Professor Heinrich thought it might also be because the raven was luring the cougar to make a kill, alerting it to a suitable target.
Whichever you choose to believe, the point is, be alert to unusual signs and sounds in the environment around you. It could help you avoid a medical emergency some day!