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Vaughn Bryant Uses Pollen to Pinpoint Where a Victim has Been and Maybe Solve a Crime

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Working in his lab at Texas A&M University in College Station in August 2006, Vaughn Bryant, garbed in a lab gown and gloves, gently lifts the blood-spattered clothes from the brown paper bags they’ve been stored in for decades.

He lays the clothes out, a button-down plaid cotton shirt, tan corduroys, blue socks, brown ripple-sole shoes, a pair of underwear, a bra and an oversize red windbreaker with black stripes down the arms, too large for the petite frame of the girl who wore it. Bryant has everything but the turquoise necklace the girl, known only as “Caledonia Jane Doe,” was wearing on November 10, 1979, when she walked into a cornfield in western New York and was shot twice, once in the back and once in the back of the head.

She has no identification, and over the years, she has never matched any missing persons report. Her body lay there all night just outside the small town of Caledonia, New York, rain washing away most of the evidence. By the time a farmer discovered her the next morning, the killer was long gone. The only hints law enforcement had about where she came from were the tan lines on her skin.

She was buried in a local cemetery under a stone marked “Jane Doe,”although investigators had quickly nicknamed her “Caledonia Jane Doe,” or “Cali Doe” for short. In the following years, tips poured in to leading law enforcement officers from all around the country. John York, the first officer on the scene, was eventually elected sheriff of Livingston County, and he continued to pursue the case. During his decades as sheriff he traveled to prisons in Texas and Florida to interview 64 serial killers who claimed to be the murderer.

The reconstructed image of the girl, complete down to the dyed blond ends of her hair, turned up nothing. When DNA testing became an accepted forensic practice, officials exhumed her body in 2005 to collect samples and conduct tests, again without any success. Despite decades of effort, she was still a girl without a name, and without an identity, there was little chance of finding her killer.

In 2006, York decided to bring in a pollen scientist to see if pollen analysis would reveal where she could have been from. “It was another option,” York says now. “I do a lot of research on crime analysis, and I’ll use any bizarre means to try and solve a crime. It never hurts to try.” Bryant was the only such scientist in the United States at the time.

Investigators shipped Bryant the girl’s clothes, still in the bags they’d been tucked into by a medical examiner more than 20 years before.

“I imagined her parents, how they must feel to have had a daughter disappear, and I wanted to help give her a name, her own name,” Bryant says now. He examined the crime-scene photos for clues, not to the murder but to the plants in the area. Bryant taped the girl’s picture to the door of his forensic lab.
He went to work, running a powerful fist-size vacuum nozzle over every item repeatedly, tucking it into the pockets of her pants, the folds of her shirt, the nooks and crannies of every piece of clothing, to pull every grain of pollen he possibly could from the clothes.

Pollen, as it turns out, is everywhere. People carry it on their clothes and skin at all times. Pollen and other microscopic grains and spores are mostly invisible to the naked eye, but under a microscope, the tiny grains can unlock all kinds of secrets, including where someone has been, where he or she grew up, or the exact location a person hid a body.

That’s because every plant produces a unique pollen grain, with everything from the shape and the size to the markings on the outside of the grain indicating what type of plant it comes from.

Law enforcement has been sending Bryant, currently one of the two forensic pollen scientists working in the United States, samples of the unidentified dead for years. Given a good sample, Bryant can pinpoint the pollen to an area of a neighborhood, a city, a state or a country. Pollen samples can be as specific as a fingerprint.

But although forensic pollen science is accepted in court cases in other countries, including New Zealand and the United Kingdom, U.S. courts are not so accommodating. Forensic pollen analysis has yet to meet the U.S. courts-mandated standard that requires proof an expert’s testimony is scientifically valid. So even though Bryant has testified in some U.S. courts, a judge has yet to accept his findings as evidence.

Bryant’s report on Cali Doe came out in August 2006 and gave investigators solid evidence about where she came from, though the possibilities were some distance apart. She was from either northern California or southern Florida, judging from the traces of spruce, oak and other plants found on her clothes.

For the past 40 years, Bryant has almost single-handedly pioneered forensic palynology in the United States. From his lab at Texas A&M University, he has helped track ivory poachers, identified batches of counterfeit honey, aided the federal government in tracking down terrorists, probed the drug trade and helped investigators put a name to unidentified bodies.

Pollen can survive almost anything, but the field of forensic pollen science, as practiced in the United States, is on a far less secure footing. Bryant has incurable cancer and is facing the fact that his life’s work, establishing the field of forensic pollen science in the United States, may not survive him.


All his life, Bryant has had a curious mind. As a kid, he devoured mystery books and loved putting the clues together to find out what the real story was. After jaunting around the globe for most of Bryant’s early childhood, his family settled in Houston when he was a teenager. Bryant attended San Jacinto High School, and enrolled at the University of Texas in Austin immediately after graduation.

Bryant had a wild streak. The first year of college, he partied and drank heavily, totaling his car twice. Realizing he was going to flunk out, he started attending Alcoholics Anonymous meetings and got an apartment across the street from AA. From then on he worked, went to class, attended meetings and studied. “I can’t do anything in moderation. I could not drink, gamble or smoke in moderation. The only way is full speed ahead or dead in the water. There is no in between,” Bryant says.

Without alcohol in his life, Bryant locked his attention on his studies. He whipped through an undergraduate degree in geography, and then chose to study anthropology for his master’s. While working on that, he got a job as a palynology assistant. “I didn’t even know what that was, but I had a wife and I was going to school and I needed a job, so I took it,” he says now. “Then I was completely obsessed.” It was the perfect field for him, because studying pollen means learning to identify thousands of pollen species — there are more than 350,000 different types in North America alone — and it takes years to become skilled at interpreting pollen samples.

Palynology has been around in some form since the microscope was invented, in the early 1600s. However, the discipline really took off in the 1930s when advances in microscope technology made it possible to closely observe and identify pollen grains and spores. After Royal Dutch Shell hired palynologists in 1946, the rest of the oil industry followed suit, creating well-funded laboratories for pollen scientists to analyze drilling samples, further advancing the discipline. Oil companies use palynologists to study layers of rocks to find variations — which are reflected in both the rocks and the ancient pollen samples found on the rocks — where pockets of oil may have built up over the centuries.

The entire field might have remained focused on academic research and oil, but in 1959, an Austrian man traveling down the Danube disappeared. The police had a suspect, a friend and business partner of the man’s with reason to want him dead, but they couldn’t find the body.

Desperation seems to have led the police to pollen science. When they found a pair of muddy boots in the suspect’s cabin, they sent the boots to Wilhelm Klaus, a pollen science professor at the University of Vienna. Klaus examined the mud and discovered a 20-million-year-old hickory pollen grain along with evidence of willows, spruce and alder. He concluded the mud could only have come from a distinct spot covered with ancient rocks and surrounded by willows, spruce and alder along a stretch of the Danube just north of Vienna.

“We know you killed him, and we know where,” the officers reportedly told the man when they had the report from Klaus. The suspect confessed and led authorities to where he’d buried the body. It was almost exactly where Klaus had predicted it would be.

Bryant’s start in forensic pollen work was less dramatic. In 1975 the U.S. Department of Agriculture hired him to track down “counterfeit honey,” a product that has been diluted with other sugars, and to make sure the honey being sold was from the place the sellers claimed. To test whether the honey was being diluted, Bryant looked at the level of pollen found in the product. He figured out where each honey sample came from by making sure the pollen grains in it were the type bees in the area would use. The department paid him for each sample, and while the pay wasn’t much, Bryant jumped at the chance to pull in funds for his newly established pollen laboratory at Texas A&M and to pay his graduate student researchers.

The hunger for research money led him to start pitching the chance for more work to law enforcement in the 1980s. Bryant traveled the country giving hourlong presentations to various local, state and federal agencies. He gave his spiel during one of the annual meetings of the Sheriffs’ Association of Texas in El Paso. Afterward the Nolan County sheriff of the time strutted up and grinned at Bryant as they exchanged business cards. “I’ve got just the case for you,” the sheriff told him.

A few months later, the sheriff arrived in College Station carrying an evidence bag. Inside were the clothes of an unknown man, dubbed “Juan Doe,” who’d been stabbed 21 times and left under a mesquite bush outside of the West Texas town of Sweetwater. The sheriff didn’t ask Bryant to look for anything in particular. In fact, the sheriff laughed as he handed over the evidence. He told Bryant investigators believed the man had been killed over drugs, so they were focusing their efforts to the south. He didn’t bring crime scene photos or any other information. It was Bryant’s first case involving an unidentified body.

After Bryant had gathered enough dirt and pollen from the clothes, he placed the collected material, the tiniest clumps of organic matter, in liquids to pull the pollen out of the dirt and make it easier to drop onto a glass slide. He spent hours going over each slide, first drawing on his vast reference collection, composed of works donated by oil companies and hundreds of books he’s assembled over the years, to identify each grain. Peering through his microscope, he counted the pollen grains on the inch-long slide and classified them by type. It takes about 200 thorough passes over a slide to gain enough scientific certainty to be sure of the count, an hourslong process.

“I never learned what happened, but I told them they should be looking up north, around Kansas City.” Eventually there was a huge drug bust in that city, he says. “I’ve always wondered if my study was connected to that.”

Over the years, his work became well known in some law enforcement circles. He took cases when his teaching schedule allowed and used the fees to fund his lab and his graduate student researchers.
After 9/11, the Central Intelligence Agency contacted him, he says. “I told them I’d be happy to do anything I could to help, but I wouldn’t go to the Middle East to collect the samples.” The federal officials sent the samples to his university lab.

He received backpacks, scarves, parts of bombs, bits of rope, all kinds of things, usually without a hint of where the items came from. Once he got a 36-inch shoelace. “We need to know where this shoelace has been,” the CIA told Bryant. No other instructions. The lace was covered with more than 5,000 grains of pollen, and Bryant quickly concluded it had been to Iran and Iraq.

“It was like playing Sherlock Holmes. I’d get these samples that could be from just about anywhere, and I’d have to figure out where they’d actually been, all from my lab here in Texas,” Bryant says.

After his work for the CIA, Homeland Security and the FBI contacted him. He went to the CIA headquarters in Langley, Virginia, so often over the following decade that agents knew him by sight. He did a little bit of everything, from going over illegal ivory to find out how it got into the country, to looking at samples of black tar heroin, as well as examining dufflebags and shoes and other random items to help track the owners.

He didn’t ask many questions. “You know you may have injured someone, killed someone with this type of work. You have to stay detached. I never asked for more information than anyone gave me. Maybe it was the chicken way out, but it’s much easier simply not to know,” he says.

With all of his cases, Bryant takes the same approach. He does the analysis, sends in his report and usually hears nothing else. “I believe I’ve helped do important things, but I don’t know it for certain,” he says. “That’s part of why I’m good at this type of work. I enjoy the puzzle, working out the problem. I don’t have to know what happens next.”


Many officials are wary of using forensic pollen science to build a case, Bryant says. For one thing, there’s the problem of how to employ such evidence in court, in large part because of the way most pollen samples are collected. “You have to have a chain of custody, you have to make sure the samples have been taken properly, you have to be extremely careful,” he says. Once, Bryant traveled to Detroit to testify, but while he was on the stand, the defense attorney contended the pollen samples could have been contaminated. The attorney asked Bryant if this was possible. “I had to say yes, because I was under oath and I couldn’t say no,” Bryant says.

There’s also the sheer lack of jobs for would-be forensic pollen scientists. When one of Bryant’s students, Andy Laurence, was hired as the head forensic pollen analyst for U.S. Customs and Border Protection in Houston, it was a coup for Bryant. Laurence is the only full-time forensic palynologist in the country.

Meanwhile, government officials aren’t rushing to hire more forensic pollen experts. “The United States forensics culture is really into the CSI stuff. They like machines you can pop a sample into and get guaranteed results in an hour,” Laurence says. “The problem is, palynology doesn’t work like that. They want all the chances for error taken out of the process, but this work takes whatever amount of time it takes, and there are no guarantees you’ll have any answers at the end of it.”

So far computers have been unable to correctly identify every grain and spore in a given sample, Laurence says. “I don’t know if they’ll ever manage to make a computer that can do it. Pollen will change and fold and expand and shrink and do all kinds of things that won’t be caught on a computer.”

Bryant says the only thing guaranteed to establish forensic pollen science as a viable option in the United States is a case in which pollen analysis plays a major role. “We need the O.J. Simpson of court cases. I know that sounds terrible, but that’s the truth of it,” Bryant says.

He thought the “Baby Doe” case in Boston was it.


In June 2015, the remains of a small child were discovered in a trash bag on the shore of Deer Island, on the edge of Boston. The child was young, between two and five years old, with long, dark, wavy hair and pierced ears. Her facial features were already distorted by death, and the body had been sitting in water so it was unlikely she’d have usable fingerprints. She was naked except for a pair of white leggings with black polka dots, the body wrapped in a zebra-print blanket.

Standing on the shore that morning, the investigator working the case made two calls. First, he called the coroner. Second, he dialed the National Center for Missing & Exploited Children to see if that organization could help. “We’re a resource law enforcement can draw on if they decide to, and then we try to help make sure the investigators are aware of the tools that are out there and the options they have,” says Mike Murphy, program manager for the center’s Missing Children Division.

About a month after the body was discovered, Carol Schweitzer, the forensic case specialist at the center who was assigned to Baby Doe, suggested investigators try pollen analysis. When they contacted Laurence, he immediately agreed to work on the case. (Bryant was ill, but assisted on the analysis.)

The National Center for Missing & Exploited Children has been advocating the use of forensic pollen analysis in certain cases for more than a year now. “We weigh what we recommend very carefully, and that’s based on whether it could be useful and whether it will be a good use of resources, since the number of people who do a lot of this type of work is very limited,” Murphy says. “Laurence is the only person we use for forensic pollen work, so we have to be selective about when we ask for his help.” Schweitzer says NCMEC is the only U.S. organization she knows of that regularly employs forensic palynology.

By then, the case was international news. The reconstructed image of the child got more than 50 million views online. Tips were flooding in from all over the world. As the investigation unfolded, police would locate more than 200 other children who were reported either missing or living in dangerous conditions. Investigators needed a way to focus their work. “We were hoping pollen would help point investigators in a direction and help prioritize the leads,” Schweitzer says.

Laurence’s report detailed pollen from two types of cedar trees that cannot grow in the wild any further south than New York. However, he concluded, both of the cedars were in the Boston Arboretum, so the child must have lived nearby.

The child was identified as two-year-old Bella Bond, who was living two blocks from the arboretum when she died.

But while pollen was used to identify the child, the evidence wasn’t presented in the trials against Bond’s mother, Rachelle Bond, or the woman’s boyfriend, Michael McCarthy. “That’s the step that needs to happen, the evidence really being used, to prove it can be done successfully here,” Bryant says.

Countries such as New Zealand have used forensic pollen work for decades, but that’s because certain high-profile cases led police and the public to accept the idea. According to famed New Zealand forensic palynologist Dallas Mildenhall, the 1983 murder of 14-year-old Kirsa Jensen, who disappeared while riding her horse, was a key case. Her body was never found. One night, in the middle of the investigation, one of the lead detectives happened to be having a beer next to Mildenhall’s father at a bar. Hearing the detective’s story, Mildenhall’s dad suggested police ask his son for help.

The only evidence was a length of rope that had been used to tether the horse. Mildenhall extracted pollen samples from the rope and found grains of broad bean, pumpkin and beetroot on it. The suspect was a market gardener, but the pollen evidence wasn’t enough to send him to court. (The man later committed suicide.) However, the case became national news and established pollen science as a forensic tool in New Zealand.

Over the following decades, Mildenhall worked about 20 to 30 cases a year, investigating everything from lawn-mower theft to murder, and developed an international reputation for his abilities. But in recent years, Mildenhall has seen his cases drop off. “The amount of forensic palynological work I get is closely connected to available funding for the police,” Mildenhall says. “I am lucky now to get three or four cases a year, usually when all other services have failed.” Mildenhall says that besides him, there are only a handful of forensic pollen scientists working in New Zealand today.

Sophie Warny, a professor of palynology at Louisiana State University, has been working with Bryant for more than 20 years. Bryant helped train her, and she’s trained dozens of students over the years, but the bulk of her students go into the oil industry, she says. It takes a special type of person to become a pollen scientist, says Warny. “This work takes a lot of time, a lot of patience. You have to be willing to put in the time and to know that it may take more than eight hours of work to find out what type of species are there and identify them. And sometimes at the end of it, you won’t get the right answer and you’ll have to start all over again.

“Some people have tried to get into forensic, but I think they get discouraged because it takes such a long time to get really good.” Warny says. “The talent all goes to oil instead. That’s where the money is.”

Over the years, Bryant has tried to persuade more people in law enforcement that what he does is a solid criminal investigation tool and they should employ it. Most often, police departments tell him they don’t have the funds or don’t think it’s worth the money.

Many assume this field can be learned in a few weeks of study with Bryant, or during a semester spent in his lab, but people have tried to learn it that way — fast — and it’s proved impossible.

“I’ve been like Moses wandering the desert for 40 years, telling everyone about this field and how it can be so much use to them,” he says. “It’s another tool to help find the truth. Why on earth wouldn’t we use every tool we have to make sure we find out the truth of things?”


Like every other cancer patient at MD Anderson, Bryant wears a white bracelet on his wrist each time he goes to the famed treatment center located in the Texas Medical Center. “I call them my ‘white badge of courage.’ You can look around the hospital and recognize the people who are also fighting for their lives because we all wear these bracelets.” He saves each one — he has more than 20 at this point.

It started in September 2014 when he kept having to get up to go to the bathroom at night. His urologist tested him and suggested he go for a biopsy, but Bryant ended up doing research instead, putting it off while he figured out the best possible way to deal with prostate cancer. By the time he started going through the rounds of tests, an aggressive form of cancer had spread from his prostate to his lymph nodes.

In April he learned the cancer had spread to his bones. Now he’s been told he has three to five years to live. Bryant is already dealing with the reality that the end of his life will likely be the end of his laboratory’s existence.

“It’s going to be impossible. I don’t think we’ll ever recover from losing someone like Vaughn,” Warny says. “For years he’s been the one to go to when you’re stumped. Once he’s gone, it will be back to the books entirely. We have amazing resources, fantastic books to work from, but it will take so much longer. It’ll be hard.”

Laurence grows quiet when asked about Bryant’s illness. “I don’t know. I talk to him every single day. I can’t imagine not doing that,” Laurence said, staring at the delicate outlines of pollen illustrations that line the walls of his U.S. Customs and Border Protection lab.

Warny is hoping to carry on what Bryant started in academia by turning her own lab into a certified forensic pollen lab. Upgrading the LSU lab will cost about $350,000, but Warny is applying for grants to fund the changes. “It just depends on if we can get the money to do it,” she says.

Bryant tries to be sanguine about the future. “He says he already knows what will happen once he’s dead. The university will close the lab and that will be the end of it. But in the meantime, he’s gotten so much joy out of his work, he says that’s enough,” Carol Bryant, his wife of 52 years, reveals.

Sitting in the lab he built, where he’s spent most of his career, Bryant stares down at his hands, his buoyant smile fading. “I don’t know what will happen to all this when I’m gone. All my samples and the work I’ve built up. I really don’t like to think about it,” he says, his voice shaking slightly. He clears his throat and smiles hard. “That’s why I work so much. If I didn’t have the work, I’d go crazy thinking about it all the time. And I’ve had a wonderful time doing this all these years.”

But he’s always been comfortable with the unknown. He did the analysis on Caledonia Jane Doe in 2006, and then the assistant medical examiner who’d suggested the Livingston County Sheriff’s Department use him for the case left the job, Livingston County Sheriff John York retired and Bryant didn’t hear anything else about the case.

He kept her picture up in his lab until she was identified in 2015 as Tammy Jo Alexander, a 16-year-old girl who ran away from home in 1979. She was from southern Florida, just as Bryant’s tests had indicated.
Once she had a name, he took her picture down. 

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