There are numerous myths about black cats and dogs: Black cats are bad luck. Black dogs are omens of death.

Such rumors are rooted in folklore and ancient mythology, but there’s one story you've likely heard about black cats and dogs that's true: They're the last to be adopted and the first to be euthanized.

In addition to the stigmas of bad luck and witchcraft, black animals also face a tough time being adopted because their dark coats often lead to poor photos. Being less photogenic means they’re more likely to be overlooked by potential adopters.

The adoption challenges that black pets face are so pervasive there’s even a name for the phenomenon: black dog syndrome.

Despite its name, black dog syndrome doesn't just affect canines.

A 2012 study found that dark-colored cats are also more likely to be stereotyped as aloof.

Researchers at the University of California asked a group of cat lovers to rate black, multicolored and orange cats on personality traits such as friendliness, laziness and stubbornness.

The findings revealed that black cats were seen as more antisocial than cats with other fur colors. Overall, orange cats were perceived as the friendliest.

Stanley Coren, a psychology professor at the University of British Columbia, conducted a similar study with dogs in 2011.

He presented participants with photos of three Labrador retrievers of different colors: black, brown and yellow.

People consistently rated the black dog as being less attractive, less friendly and less likely to make a good pet. The black Lab was also deemed to be the most aggressive of the dogs.

The American Society for the Prevention of Cruelty to Animals says the adoption rates of black cats and dogs aren’t tracked nationally, but the organization assures potential adopters that they make great — and stylish — pets.

After all, black goes with everything.

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