Image Gallery: Pets
Image Gallery: Pets

Image Gallery: Pets Cats are normally associated with being aloof and independent. Do they have a sixth sense regarding imminent death? See more pet pictures.

Image courtesy Anna Humphreys/stock.xchng

In July 2007, a fascinating story emerged in the New England Journal of Medicine about a cat that could "predict" the deaths of patients in a nursing home several hours before they died. Oscar, a cat adopted by the staff of the Steere House Nursing and Rehabilitation Center in Providence, R.I., has at least 25 successful predictions, in which patients died hours after the cat sat down by their beds. After the nursing home's staff caught on to Oscar's ability, they began alerting families whenever the cat took up his post next to a patient. Most families tolerate or even welcome his presence, though Oscar becomes upset if forced out of the room of a dying patient, meowing outside the door.

Oscar's actions appear deliberate. He regularly wanders around the home's unit for patients with advanced dementia. He sniffs and watches a patient before sitting down with her. Oscar then purrs while sitting with the patient and usually leaves soon after she dies.

How does Oscar do it? Is it a "sixth sense," a unique scent he smells or something else? Animal experts have put forth a variety of explanations, though most agree that it likely has to do with a specific smell produced by dying patients. That is, people who are dying emit certain chemicals that aren't detectable by other humans but that may pique Oscar's heightened sense of smell. An expert on felines said that cats can sense sickness in their human and animal friends [Source: BBC News]. Jacqueline Pritchard, a British animal expert, told BBC News that she was certain that Oscar was sensing vital organs shutting down [Source: BBC News].

As for why he keeps vigil next to patients, Oscar may be mimicking the behavior of staff who spend time with dying patients. One animal expert suggested that it may be as simple as Oscar enjoying the comfort of heated blankets placed on dying patients [Source: NPR].

Stories of animals with startling abilities aren't rare. Tales have long existed of dogs detecting various types of cancer with their sense of smell. A study later proved that dogs could sense evidence of bladder cancer by smelling it in urine. Some people who suffer from serious epilepsy use specially trained dogs provided by charities. These dogs warn their owners of impending seizures by licking or some other signal. One woman said that her dog regularly gives her a 40-minute warning, allowing her to get to a safe place so as not to worry about the seizures putting her in danger [Source: BBC News].

The seizure-sensing dogs look for subtle smells and changes in features of their owners (such as dilated pupils). Their training, which takes at least a year, teaches them to warn their owners. While we're used to hearing about dogs learning to help the blind or search out injured people, Oscar's case is more puzzling. Cats, unlike dogs or even elephants, aren't associated with altruistic, empathic behavior. Scientists believe that dogs can sense disease in others because of their evolutionary origin as wolves, who needed to be able to detect when someone in the pack was hurt or sick.

We've found some rational explanations for Oscar's actions and those of seizure-sensing dogs -- subtle smells, dilated pupils, learned behaviors -- but what about other strange animal behavior? Can some animals really sense earthquakes or feel compassion? On the next page, we'll delve into the world of ethology.