Scientists think they know why a Chihuahua will outlive a Great Dane

Saint Bernard owners, you might not want to read this. Scientists believe they've determined why small dogs tend to outlive their larger counterparts. Researchers in Germany analyzed the deaths of 56,000 dogs — representing 74 different breeds — and learned that "large breeds apparently aged at faster rates" than terriers, toys and other pint-size pets. According to their research, every 4.4 pounds in body mass deducted a month from the animal's life expectancy. "[Large breeds'] lives seem to unwind in fast motion," evolutionary biologist (and admitted "dog nerd") Cornelia Kraus said. The scientists plan to build on this study, attempting to narrow down the "leading causes of death" among larger dogs. [Source]

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