If Dr. John Hafernik is an indication, never take the observational prowess of a scientist for granted, even on a route he walks almost every day.
"You're always looking, always thinking about what is going on," he said.
For instance, one morning two years ago when he first noticed the mystery outside Hensel Hall on the San Francisco State campus.
"I look around and there are all these bees on the tarmac," Hafernik said.
He knew they came from a hive down below and that in the cold weather they should have remained inside. There were dozens of dead bees, then, as now. And the dying ones were wandering about in a very un-honeybee-like way.
Being the curious sort, Hafernik scooped a few bees into a test tube, carried them upstairs and brought them to his office.
"One of the great things about science is serendipity," Hafernik said.
And then a week passed. The doctor didn't pay any attention at all to that vial, and then he looked.
"I looked at it and there were all these brown pupae in it. I knew they were flies," Hafernik said.
That's when the doctor knew he had made an accidental discovery. Until 2006, no one had seen or heard of colony collapse disorder, either. It remains unexplained, a threat to honeybees worldwide, and especially in the United States.
"Well beekeepers would come back to their hives and basically all the bees would be gone, the bees would just have left," Hafernik said.
Could there be a link? Hafernick and his students went to work, collecting DNA from the maggots as they emerged. They identified one specific species of forage fly.
After examining the bees came another surprise.
"There was nothing left inside the bee," Hafernik said.
The cycle begins once a fertile fly finds a bee, and uses an appendage called the ovipositer to penetrate the body and lay eggs. They eventually hatch, inside as maggots -- lots of maggots, according to the research team.
"The record is 25 maggots in a single bee," researcher Christopher Quock said.
"They eat them; eat them from the inside out," Hafernik said.
Beginning in the abdomen, moving onto wing muscles, and the brain. Eventually, those maggots pop out between the head and thorax.
"It's kind of a bee's worst nightmare," Hafernik said.
Could this be the source of colony collapse disorder? It does create the symptoms.
"It certainly could be part of the answer, at any rate," Hafernik said.