Unexpected honor

For her years of painstaking work and her contribution to science, alumna Kathleen Ritterbush ’06 has ancient ammonite named after her.

Photo: Mariam McFerrin

When a friend from graduate school recently sent Kathleen Ritterbush’06, PhD, a link to a 20-year-old research paper, she was mystified at first about the reason.

“I looked down and thought it was that paper from 2001 … I didn’t read the title very carefully,” Ritterbush said. But her friend urged her to read the paper, titled “Early Sinemurian Ammonoids and Biochronology of the Sunrise Formation, New York Canyon, Mineral County, Nevada.”

She soon was delighted to discover that the co-authors, Jean Guex and David Taylor, named an ancient ammonite, Arnioceras ritterbushi, after her.

Ammonites were squid-like animals with seashells resembling snails that lived during the time of dinosaurs and earlier, about 300 million to 65 million years ago. Because ammonite species evolved and went extinct relatively quickly, discovering and identifying fossils of their different species in layers of sedimentary rock helps scientists pinpoint specific time periods. Discovering the same ammonites and layers on multiple continents has helped scientists understand geological events such as the breakup of the supercontinent Pangea.

Having a fossil named after you is an increasingly rare honor because fewer scientists today specialize in biostratigraphy, the science of using fossils to assign ages to rock and sedimentary formations, Ritterbush said. Biostratigraphers often are the scientists who discover new ammonite species.

Ritterbush is a paleoecologist, a scientist who studies ecosystems of the past, and has a passion for teaching science, which is ironic considering she never wanted to go to Cal Lutheran or be a scientist, especially a paleontologist. Her mother, Linda Ritterbush, PhD, Cal Lutheran professor emeritus, is a paleontologist who spent her career studying paleoecology. However, she didn’t want to follow in her mother’s footsteps.

After graduating from Thousand Oaks High School, she attended Cal Lutheran, planning to major in philosophy with the goal of becoming an architect. However, a marine biology class helped change her trajectory. During a winter interim session in her sophomore year, she went on a field trip to Hawaii to stay on a research boat and study marine life. At the end of that trip, her professor suggested she stay on the boat, an idea she loved. Ritterbush told her parents she was leaving school, packed a bag and flew back to live on the boat and teach marine biology to teenagers for six months. By the time she returned to Cal Lutheran, she knew she wanted to be a scientist and teacher. She graduated with her bachelor’s degree in environmental science.

While working on her PhD in earth sciences at the University of Southern California, she traveled to New York Canyon, an old silver mining area in Nevada, one of the best places in the world to study fossils and sedimentary rocks from Jurassic seas. That trip led her to do her PhD research on what happened during the mass extinction event between the Triassic and Jurassic periods. She and fellow graduate students spent years traveling to New York Canyon, not fully understanding what they were seeing in the rocks. They tried mapping the layers, and knew bits of microscopic trash from sponges were in the rocks, but the odd shapes they saw didn’t make sense.

“Eventually as I was trying to draw illustrations of what I thought this would have looked like if I was snorkeling over it, I thought, what if the sponges were actually sitting there on the sea floor when the storm swept around them, but didn’t totally obliterate all of them, and some of them got caught like Pompeii?” she said.

This revelation ended up being a turning point in her research. She discovered that most of the layers of rock that represent the first 2 million years of the Jurassic period in that area are made predominantly by sponges. No one had ever looked at the rocks that way.

Ultimately, that discovery is why Guex and Taylor chose to name an ammonite after her, she said. The ammonite also is assigned to a distinct layer of ancient time or horizon of rock — Ritterbushi horizon.

“Getting an honor like somebody recognizing my work and naming a new species of my favorite animal after me because they recognize that the work I did was helpful — I can’t even express what a professional compliment that is,” Ritterbush said. “And I still have not written them a thank you letter because I have just been at a loss for words. I just don’t even know what to say.

CLU Magazine

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