Portside

If you ask a dog "How are you?" it will probably just wag its tail and wait for you to start playing. "Optimist" would be a fair label for dogs in general. But are some pups, notwithstanding all of the tail-wagging, inherent pessimists?

New PhD research out of the University of Sydney by Dr. Melissa Starling, from the school's Faculty of Veterinary Science, sought to find out if dogs had underlying personalities that tended toward either optimism of pessimism.

Starling began by teaching a group of dogs to identify two distinct tones, each an octave apart, and associate each tone with receipt of either a yummy bowl of milk or a plain old bowl of water.

Once the dogs had that down and knew "yummy" tones from "eh, water" tones, Starling threw them not a bone but a tonal curveball. She began to play "ambiguous" tones for the pups -- tones that were in between the "milk" tone and the "water" tone.

If a dog responded to the ambiguous tone with the kind of enthusiasm it had when it heard the milk-treat tone, the pup was termed "optimistic." These were bowl-half-full dogs, the kind expecting good things to happen. Such dogs are risk-takers, bright-eyed calculators of risk-vs-reward.

Dogs that did not respond to the ambiguous tone were considered more pessimistic. These bowl-half-empty'ers had Eeyore-ish personalities. Such cautious canines expect more bad things to happen than good, and they'll tend to be on the cautious side, easily discouraged when things don't go well.

Pessimistic dogs aren't "unhappy," according to the study; they're just happiest with things the way they are, and they might need a bit of a nudge to try new things.

Why does this matter? Dog owners everywhere tend to feel they have a good handle on their pet's personalities. But there are some benefits to being able to discern a given dog's pessimism or optimism, according to Starling. Dog trainers, for example, would be well served by knowing which animals are optimists and which are pessimists.

"If we knew how optimistic or pessimistic the best candidates for a working role are, we could test dogs' optimism early and identify good candidates for training for that role," said Starling in a press release. "A pessimistic dog that avoids risks would be better as a guide dog while an optimistic, persistent dog would be more suited to detecting drugs or explosives."

Starling has been working with an Australian charity that provides service and companion dogs to the disabled, researching whether an optimism gauge would help find the best dogs for training.

And, in total, did optimism triumph over pessimism? "Of the dogs we tested we found more were optimistic than pessimistic," Starling said. "But it is too early to say if that is true of the general dog population."

Starling's research has just been published in the journal PLOS One.

Richard Farrell has produced and written articles for Discovery Web sites since 2010. He has edited technology trade magazines and programmed and directed multiple publication Web sites. He lives in Northern Virginia and is an expat Red Sox fan.