Evolutionary Biology and Ecology Ph.D. Student Keyi Feng is exploring the evolutionary history of the carnation family (Caryophyllaceae) using specimens from the U-M Herbarium. Her work combines plant phylogenomics and DNA sequencing to better understand how the  Caryophyllaceae is the only eudicot family that spans all seven continents.

“My primary focus is on phylogenomics,” Keyi explains. “I use herbarium specimens for DNA sequencing—some over 100 years old!—to build comprehensive evolutionary trees for the carnation family.” By sampling 50–60 specimens from the U-M Herbarium’s collection, along with specimens from other herbaria, she extracts DNA and prepares it for sequencing using a technique called target enrichment, which captures hundreds of conserved genes across flowering plants.

Herbarium specimens, even ones collected decades ago, provide invaluable genetic information. “Some DNA can be degraded depending on how the specimens were preserved,” she notes, “but surprisingly, most of the samples work reasonably well.”

These sequences allow Keyi to investigate ancient polyploidy events—whole-genome duplications in the family’s history—that may have driven unique adaptations, including survival in alpine and Arctic environments. One species even exists in Antarctica (Colobanthus quitensis), and the U-M Herbarium has collections of this species.

Having access to the U-M Herbarium collection is a huge advantage. “If I couldn’t visit the U-M Herbarium, I’d need to coordinate travel to multiple herbaria around the world,” said Keyi. “Here, I can focus on sampling a wide variety of species, especially those that are alpine or Arctic-adapted.”

Her work not only reconstructs the evolutionary history of a famous ornamental plant family but also demonstrates the lasting scientific value of herbarium collections. “It’s incredible to see that specimens collected over a century ago can still contribute to modern genetic research,” she says.