By Michelle Watson, science communications intern
Geology & Geophysics doctoral student Shannon Ferguson contributed to the investigation that led to the identification of the body of Bella Bond, the two-year old toddler discovered on the shores of Deer Island in Boston on June 25. This past summer, Ferguson interned with the Department of Homeland Security, or DHS, in Houston where she worked with head palynologist, Dr. Andrew Laurence, in Customs and Border Protection, to track the origin of confiscated drug paraphernalia and other items. However, it was her work on the Baby Doe murder case that had the greatest impact on her summer internship experience.
As part of her internship, Ferguson assisted Dr. Laurence, her DHS supervisor, in the analysis of the pollen found in Bella’s hair and clothing. It was the results of this analysis that gave investigators their first break in the case. Based on the pollen found on Bella’s clothes and blanket, it was determined that she was from the local area prompting police to focus their search in Boston.
Bella’s body was found June 25. After weeks of news coverage and virtually no leads in the child’s identity, she was referred to as Baby Doe. Earlier this month, the little girl was identified as Bella Bowman. Bella’s mother and her mother’s boyfriend have been charged in her killing.
To help investigators identify Bella, DHS palynologists combed through her hair and clothes for remnants of pollen and other forensic evidence that could be used to geolocate where she came from. The scientists used tiny vacuum cleaners to suck up the pollen grains through a filter. After that, the samples underwent chemical processing to isolate pollen grains, and this is what Ferguson, Laurence and a team of scientists examined.
“Pollen has a wide utility, because it’s everywhere,” said Ferguson, “What ever question you’re trying to answer, it can help. It’s not going to be perfect, but it’s going to get you close and definitely in the right direction.”
Used most often to date and track climate change, palynology is becoming a key factor in forensic studies. Palynology is the study of organic-walled microfossils like pollen, spores and dinoflagellate cysts (a type of plankton) that can be used to locate the origin of objects, to date sequences or reconstruct past environmental conditions. The study of palynology falls under the bigger umbrella of paleontology and geology.
“Narrowing pollen to a certain region can be a tricky process. For example, oak and pine trees are two of the most common plants found in the Southeast region of the United States. Studying any object that’s found in the Southeast region will most likely have both oak and pine pollen grains on it,” said Ferguson. “It all comes down to the trace elements of rare pollen types that help determine the location of the object. Usually there are only one to three pollen grains that will help pinpoint the location even better.”
Ferguson, now in her final year of her PhD studies in LSU’s Department of Geology & Geophysics, is funded by a Curatorial Assistantship from the LSU Museum of Natural Science Palynology Collection. At LSU, Ferguson is learning to identify pollen, build the pollen online database, and use the pollen to reconstruct environmental changes in the Gulf of Mexico.
“I always knew I wanted to do geology since third grade,” said Ferguson, “We went to Desoto Caverns in Alabama for a field trip, and I told my dad, ‘It’d be cool if I could play with rocks all day.’” Ferguson’s dad assured her there was a career path for people interested in rocks.
Ferguson became interested in palynology while studying under Fred Rich, her advisor at Georgia Southern University. When she enrolled in the PhD program at LSU, she began working with Sophie Warny, associate professor of palynology in the Department of Geology & Geophysics and curator of palynology in LSU’s Museum of Natural Science. In 2013, Professor of Palynology Vaughn Bryant, who is also considered the father of forensic palynology in the U.S., invited Warny to a DHS/FBI meeting in D.C. to discuss the use of pollen in forensic cases. This meeting lead to a forensic project funded by the National Center for Biomedical Research and Training at LSU under the governance of Jim Fernandez. The forensic training Ferguson acquired while working with this project and the connections she made are what landed her the internship.
Currently, Ferguson is working on a project with Warny using software called Specify that helps digitize pollen grains. There are presently about 12,000 pollen species in the LSU CENEX collection. Because there’s so much unknown pollen in the world, Ferguson said it could take decades to sort through. The collection had not been digitized before because most laboratories don’t have the time or the funding to sort through pollen, measure it, take pictures, and upload it to a computer with a name and description. But digitizing the pollen grains is essential to build the type of database needed to identify the different types of pollen in forensic and other cases.
When not knee-deep in pollen research, Ferguson is a runner participating in marathons like the Louisiana Marathon and the Atlanta, Georgia Peachtree Road Race. For the future, however, Ferguson is happy as long as she gets to examine pollen.
“Solving any question with pollen is interesting to me. No matter if its dating oil-bearing sequences, or forensics, I want to learn everything, there’s always more to know.”
Photo: Shannon Ferguson, LSU PhD student in palynology, photographed in front of a
scanning electron microscope at the Department of Homeland Security in Houston. Ferguson
was trained to used the microscope during her DHS internship.