Barnes, 70, had time to catch a matinee in Fairbanks because after 38 years he recently retired from the University Alaska Fairbanks.

Before he caught “Blitz” at Goldstream Cinemas in Fairbanks, Barnes filled his 1 billion seconds since August 1986 with revelations about how ground squirrels, black bears, yellowjackets and wood frogs endure Alaska winters.

With many students and colleagues from the Institute of Arctic Biology (of which he was director), Barnes studied these creatures in the forest, in the lab, and outside his home in Fairbanks.

It was there in spring 1996 that Barnes invited me to join his students who were studying the overwintering physiology of five wood frogs. The frogs were then frozen solid in a wooden box outside his garage.

One of the students, Steve Trumble, looked at a graph. It showed that the temperature within a frog’s hibernacula of snow and moss had dropped to 10 degrees Fahrenheit in the preceding weeks.

“That guy’s toast,” Trumble said.

No wood frog had been known to experience that temperature while hibernating and live to hop away.

But — surprise! — all five of those frogs later twitched back to life after thawing in Barnes’ garage. It was then a cold-temperature survival record for hibernating wood frogs.

The students theorized and later demonstrated that experiencing nature’s fall sawtooth pattern of freezing and thawing better prepared a frog to survive low temperatures than did cooling frogs steadily in a lab, where they perished at 18 degrees.

Barnes went on to discover that the farthest-north frog survives freezing as its liver produces sugary glucose that floods its eyeballs, heart and brain to prevent cell damage.

That night at Barnes’ and his wife Alison York’s home — where he estimated they have hosted at least 300 potlucks for students and scientists over the years — was a good example of his inclusive nature. As well as his fun, accessible research.

His soft manner of speaking and his ability to describe homeostasis while never using that word makes him one of my favorite interviews.

Barnes, a talented writer who landed a 10-year grant to study ground squirrels shortly after he arrived in Fairbanks, seemed to hit the newsworthy button more often than most scientists.

In 1989, for example, he got an arctic ground squirrel on the cover of the journal Science. He had found that the shoe-size animals lower their body temperatures below zero degrees Celsius when hibernating, something humans did not think mammals could accomplish without dying — or at least getting nipped by frostbite.

In 2011, he and colleague Øivind Tøien — whom Barnes met during his sabbatical year in Norway and soon after lured to Alaska — wrote up a study on black bears’ hibernation.

That paper again appeared in Science. After the report’s publication, the leaders of the association that publishes the journal flew Barnes and Tøien to Washington, D.C. for a media event.

Tøien and Barnes had built hibernation dens for problem black bears brought north from Anchorage. They monitored the bears over a winter in a protected spot on the University of Alaska Fairbanks campus. From those bears, Barnes and Tøien learned how hibernating bears do things we cannot — like maintaining their bone mass and strength when they are not moving, recycling their urine and slowing their heart rates to four beats per minute.

Barnes’s name was in a major Science article again last year, atop a story on how a warming Arctic is affecting the reproductive timing of his beloved ground squirrels.

His efforts at Toolik Field Station off the Dalton Highway in northern Alaska — which he began skiing into in the late 1980s in order to dig out buildings and snowmachines before he could do his research — helped establish a quarter-century of temperature records that enabled the 2023 study.

Temperatures at Toolik Field Station over the last 25 years have risen 1.2 degrees Celsius, about the same as the whole planet’s increase since the Industrial Revolution.

Toolik, located 370 miles north of Fairbanks and America’s only Arctic research station, covers 34 acres upon which up to 175 researchers gather at one time, most of them in summer. There, scientists from all over the world study things from fish to tundra plants to arctic ground squirrels.

Barnes was Toolik’s first science director.

“To help develop it into a world-class research station has been a joy,” he said in a recent interview.

Barnes spent many hours tossing carrots into live traps in the far north to lure ground squirrels for study before later releasing them. Experiences like that are an advantage of doing biology in Alaska when compared to institutions where researchers only perform animal experiments in labs.

“We went out to where animals lived and studied there,” he said. “We get to study freely living, roaming populations of animals.”

Likewise, during his classes where students studied wood frogs and yellowjackets, Barnes and his students “could just bundle up and head out into the (UAF campus) woods.”

A Californian by birth and through graduate school, Barnes liked the direct, generous people of Fairbanks from the day he arrived. Later, as he discovered that his sensors needed refinement and that arctic ground squirrels were indeed dropping their body temperatures colder than an ice cube, he appreciated the expertise of those around him.

“It was great to be here at UAF,” where people like permafrost expert Tom Osterkamp knew about ground temperatures and ice crystal nucleation, Barnes said. “There was just a rich faculty here who could help me explore life below zero.”

Barnes and Alison, a fire-science expert at UAF, will remain in Fairbanks even though their two daughters have fledged to Illinois and California. He can’t imagine another place that fits as well as this. He also wants to give back to Alaska, as a spawning salmon returns nutrients to its birth stream.

“After having the opportunity to live and learn here and become wealthy in knowledge and fellowship — and with a home here — I want to give back to this community,” he said.

That home in which many students and professors have eaten and laughed and debated is the only one Barnes and York have owned during their decades in Fairbanks.

The same can be said for the position of “reproductive endocrinologist working on seasonal physiology of vertebrates” that Barnes accepted upon his arrival in Fairbanks so long ago.

“It’s the only job I’ve ever had.”

Since the late 1970s, the University of Alaska Fairbanks’ Geophysical Institute has provided this column free in cooperation with the UAF research community. Ned Rozell ned.rozell@alaska.edu is a science writer for the Geophysical Institute.