Néva Meyer, assistant professor of biology at Clark University, remembers how she became interested in studying animal life at its beginning stages. She was an undergraduate student in molecular biology at Purdue University, with her eye on a career in cancer biology. Then she saw her first chicken embryo.
“I fell in love with it. I love the visual aspect of science, and I find developing embryos beautiful,” Meyer says. “To me, developing embryos are amazing — how you go from a single cell to this complex organism. Things are always moving around in time and space. Cells are moving around, and they change how they respond and who they talk to.”
As a doctoral student at the University of Washington, Meyer examined how different types of neurons develop in the chick spinal cord. In her postdoctoral fellowship at University of Hawaii’s Kewalo Marine Laboratory, she began focusing on annelids, a group that includes over 17,000 species of segmented worms.
Now an evolutionary biologist at Clark, Meyer has continued investigating the formation of complex centralized nervous systems in annelids, specifically a marine worm called Capitella teleta, research that recently landed her a three-year, $508,142 grant from the National Science Foundation.
“Many animals have a centralized nervous system where neural cells, or neurons, are clustered together; an example is the brain and spinal cord of humans. This arrangement of neurons is thought to provide better integration and more sophisticated processing of information,” Meyer says. However, she adds, scientists do not fully understand how complex centralized nervous systems arose in different animal groups, and how those systems compare. That’s what she aims to further explore in annelids, thanks to the NSF grant.
“Annelids are important for studies of neural development because they have centralized nervous systems with thousands of neurons that easily regenerate,” she says. “There are annelids that can regenerate their entire brains — if you chop off their head, they regrow their entire head. And there are other annelids — like the one I study — that can regrow their nerve cord, which is analogous to the human spinal cord. If you chop Capitella teleta posterior to the mouth, it will regrow the whole body with its nerve cord.”
As part of her groundbreaking research, Meyer is instilling her fascination of embryo development in a new generation of scientists. The NSF grant augments undergraduate projects in her Developmental Biology course and supports biology students working in her lab: doctoral candidates Allan Carrillo-Baltodano and Abhinav Sur and undergraduates Ashley Renfro ’19, Amiel Jaggernauth ’18 and Ann Kim ’18.
Just recently, Carrillo-Baltodano was first author on a journal article with Meyer. Titled “Decoupling brain from nerve cord development in the annelid Capitella teleta: Insights into the evolution of nervous systems,” their paper — which won an award from fellow scientists for first author Carriollo-Baltodano — was published in Developmental Biology. (See related story.)
Clark students aren’t the only ones benefiting from Meyer’s mentorship. The NSF also will support her science activities for junior and high school girls through Girls Inc. of Worcester’s Eureka! summer program, and her development of a teaching module to help local high school students better understand the development and diversity of centralized nervous systems in animals.
As a doctoral student in Seattle, Meyer volunteered to work with high school teachers through the Fred Hutchinson Cancer Research Center’s Science Education Partnership. She’s continuing that outreach at Clark, where she has mentored local high school students in her lab and, over the past six summers through Eureka!, has led science activities for sixth- and seventh-grade girls in the classroom and in the field.
Her activities include real-life applications, whether students are collecting and investigating samples of plankton from nearby Crystal Pond or discussing the effects of the Deepwater Horizon oil spill on marine life in the Gulf of Mexico.
“We look at the effects of environmental pollutants on developing embryos,” Meyer says. “We talk about the effect of oil spills on marine animals, and how water with oil in it can lead to developmental defects and kill their embryos and larvae. I try to tie that to: If you are pregnant, and you ingest certain substances, that can lead to improper development in the baby.”
As she studies Capitella teleta, Meyer likewise recognizes the wider implications of her research.
“A lot of the discoveries we developmental biologists make end up getting translated to humans,” she says. “If you regrow a nerve cord, you have to understand how you remake all the connections — how do you get the right neurons in all the right places, in the right way? That has a lot of implications for human medical research.”