Spring is officially here and that means flowers, gardens and bugs. At least one man couldn't be happier about the return of insects — especially the ones that hurt.

University of Arizona entomologist Justin Schmidt has spent three decades traveling the globe collecting ants, bees and wasps to develop the Schmidt Sting Pain Index. It ranks pain on a scale of one to four, with four being the worst. Schmidt has been stung well over 1,000 times and ranked 78 different insects.

"The sting pain scale was basically a scientific tool because I had no numbers for pain," he says. "You know, people just said, 'Oh, ouch that really hurt!' Or, 'Gee that really agonized me!' Those you can't put into a computer and compare them."

The most painful? The tropical bullet ant. He describes it as a "branding iron or a bolt out of nowhere."

Despite all he has endured, Schmidt says he's no masochist. He just figures being stung is the price he must pay to know more about insects — and how they use pain to survive.

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