The wonders of the animal-human bond never cease amaze us. We hear time and again how pets improve our moods, motivate us to exercise -- and sometimes literally save our lives. Stories like this will never get old:
A 43-year-old U.K. woman discovered she had breast cancer thanks to her dog named Penny. Sharon Rawlinson finally made a doctor's appointment after Penny spent weeks attending to the area where a tumor was growing.
"Penny was pawing me for weeks," Rawlinson told The Sun. "She would gently paw me as if she was trying to get something out of my left breast, but I ignored it. When she stood on me in the middle of the night and wouldn't get off, the pain was like a thousand bee stings, and the next day I felt bruised."
She thought the resulting lump was the work of Penny -- but decided to get it looked at anyway. The doctors discovered it was cancerous and Sharon began chemotherapy -- after which Penny never sniffed at her breast again.
Penny's detection was not a one-off phenomenon. A 2011 study found that specially-trained dogs could detect a tumor in 71 percent of patients. How? It is believed that "tumors produce chemicals, including low concentrations of alkanes and aromatic compounds, which dogs can detect."
"They are far more attuned to us than any other species," said Dr. Jacqueline Boyd, course leader for animal biology at Nottingham Trent University. "There is a lot of anecdotal evidence to say dogs have detected cancers and they are very responsive to things. It doesn't surprise me this dog detected its owner's cancer."