By Susan Milius
Amid all the panting, a dog at play makes a distinctive, breathy exhalation that can trigger playfulness in other dogs, says a Nevada researcher. Yes, it might be the dog version of a laugh.
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“To an untrained human ear, it sounds much like a pant, ‘hhuh, hhuh,'” says Patricia Simonet of Sierra Nevada College in Lake Tahoe. However, this exhalation bursts into a broader range of frequencies than does regular dog panting, Simonet discovered when she and her students analyzed recordings.