Bruce Wardlaw is pictured at his home in Herndon, Va. He is the chief paleontologist for the U.S. Geological Survey. (Sarah L. Voisin/Post)

The last time the government shut down, the potted jade plants in Bruce Wardlaw’s office nearly died. He showed up at headquarters in Reston a couple of weeks in to water them, but was turned back.

So, before leaving the office Tuesday, Wardlaw, the chief paleontologist for the U.S. Geological Survey, gave his fleshy succulents a good dousing. The 39-year-veteran federal employee is hopeful that he and his colleagues will be back before the plants are parched.

Wardlaw studies catastrophes — long ago planetwide bouts of destruction — with the hope that if we understand what went wrong a few hundred million years ago, we can prepare for a future catastrophic event. Wardlaw doesn’t want to stop working, and he can’t understand why he’s locked out of work by what he sees as a catastrophe of Congress’s own making.

“When that’s all they do day-to-day, you’d think they could accomplish something in a day. Their time scale is in the here and now. Ours isn’t,” he said. “It’s the inaction that’s frustrating and disappointing.”

Part of his disconnect with the way political Washington works comes from his own particular relationship with time. On non-trash days, he says, he usually gets to the office from his Herndon area home between 6:38 and 6:45 a.m. Once there, accompanied by tens of thousands of mini-fish fossils and a velvet Elvis on the wall, he uses his long days to try to put more precise time stamps on hundreds of millions of years of the Earth’s history.

One of the key things to know about Bruce Wardlaw — other than that he gravitates toward black jeans at work, black jerseys when coaching his girls’ basketball team and that he has AC/DC’s “Back in Black” as his ring tone — is that he doesn’t do dinosaurs. He does micro-fossils, particularly conodonts, a primitive little fish that had teeth good for grasping and grinding food, but essentially no jaw. They were four centimeters long.

“As you get larger in size, there are fewer individuals. Dinosaurs are pretty rare,” Wardlaw said. But conodonts — “they were everywhere.”

The little fish thrived starting 550 million years ago and into the middle of the Mesozoic Era, which ended 65 million years before Monday’s midnight deadline for passing a continuing resolution to fund government operations. Turns out that was a good stretch for studying very tough times on planet Earth, and the conodont is an excellent guide. Finding conodonts can be rather involved. When he’s not locked out of the building, Wardlaw can put big chunks of rock into his lab’s chipmunk crusher to break them up and then soak them in a plastic dish tub filled with what amounts to very strong vinegar.

The pieces are doused with other, more potent chemicals and run through a powerful magnet to sort out the chaff from potential conodonts. Then he puts sand-grain-size pieces under a microscope to search for his old friends.

Although he’s become quite fond of them, it’s not a fanciful exercise. The presence, and color, of the micro-fish remains is an important piece of intelligence.

They and other factors allow him to tell Bureau of Land Management officials whether there could be oil or gas in the ground, vital information for industry. If there’s no chance of such deposits, that can also speed up preservation work, he said, citing studies he has been involved with in Utah and other western states.

Wardlaw and all but about 40 of his fellow 8,500 U.S. Geological Survey employees nationwide are furloughed, said Matthew C. Larsen, associate director for climate and land use change. A skeleton crew is keeping earthquake, satellite and river monitoring going, but vast amounts of work, such as crucial instrument maintenance and environmental research on DDT samples, has stalled, Larsen said.

During the 1995-96 shutdown, Wardlaw and his fellow workers were eventually given back pay, but he isn’t counting on that this time.

Wardlaw is married and has four grown children. He has risen to the top of his pay scale, making $155,000 a year. He says he can handle five days with no pay. But weeks would cut a major financial hole, and lower-paid employees, such as the security guards who run the metal detectors out front, “are really going to be hurting.”

Wardlaw’s fascination with the history of the Earth has taken him to craters and mountain ranges, Pakistan and China. Among the projects on his desk as the shutdown hit was a study seeking to find a major new copper deposit in Afghanistan. Two years ago, he taught a short course at the Afghan Geological Survey and the country’s mining ministry.

The shutdown is already good news for Dusty and Daisy, Wardlaw’s long-hair, brindled miniature dachshunds, and his grey-and-white cat Sasha, who leaps atop the kitchen table that has become his new workspace, noodling for attention. He’s an adjunct professor at University of Texas at Arlington, which means he is still able to do some work on the science that has defined his life, no matter how long the lockout stretches.

A couple of decades ago, Wardlaw said, geologists knew that the Earth faced its most destructive bout of mass extinctions 250 million years ago, plus or minus  5 million years or so. About 75 percent of everything died off, he said. Now, geologists have pegged it at 252 million years ago, plus or minus 100,000 years.

Wardlaw and his humble fish are one big reason the clock has gotten more precise.

“We are getting better and better resolution on our time scale,” he said. “Getting the timing right means we can work out cause and effect.”

And that matters, he says, because, “right now, we’re experiencing an extinction event. Man has dramatically changed the Earth’s environment.”

Humankind has sped the pace of extinctions over the past century or so, he said. “Eighty to 100 years, that’s nothing on the geologic scale. That’s essentially the same time,” he said.

Looking back 252 million years ago, using geologic findings from Vietnam and elsewhere, scientists can better parse what role high concentrations of carbon dioxide played in that earlier bout of destruction.

Other work Wardlaw is engaged in has given him an unusually precise view into sea levels over the course of the past 6 million years.

He calculated that back when the oceans were two degrees Celsius warmer than they are today, sea level was 35 meters higher. It’s the kind of change that could displace vast swaths of humanity, and the kind of work he’s not willing to put down while Washington fights.

For people who love what they do, and work all the time, “there’s no sharp line between work and play,” he said. “It’s a fascinating time to study the extinction of things.”