Joe Parker Named MacArthur Fellow

The John D. and Catherine T. MacArthur Foundation has selected Joe Parker, assistant professor of biology and biological engineering, Chen Scholar, and director of Caltech's Center for Evolutionary Science, as a 2024 MacArthur Fellow. The MacArthur Fellowship is an $800,000, "no strings attached" grant awarded to individuals in a variety of fields who have shown "exceptional originality in and dedication to their creative pursuits."

Parker is an evolutionary biologist and entomologist whose work focuses on understanding the origins of symbiotic relationships between different species of organisms, with a specific focus on insects. He has pioneered the study of tiny insects called rove beetles in order to illuminate fundamental questions regarding the evolution of interspecies interactions.

Parker began studying rove beetles as a teenager. Most of the 67,000 known species of rove beetle live independently as predators in leaf litter and soil habitats around the globe. Parker's early work revealed how, from this ancestral ecology, numerous lineages have evolved remarkable chemical, behavioral, and anatomical features that allow them to survive and thrive inside ant colonies, where they are accepted into the ants' social system. Bringing his deep knowledge of these insects to Caltech, Parker and his team harnessed this unique branch of the tree of life to uncover how new and intricate forms of interspecies relationship emerge via evolutionary changes in these beetles' genomes and cell types.

In 2021, Parker's group published a study that revealed the evolutionary steps by which rove beetles evolved a chemical defense gland that allows them to diversify in hostile, ant-dominated ecosystems. These findings revealed the processes by which new cell types are stitched together and evolve to cooperate with each other during evolution, yielding novel organs. This work represented a breakthrough in utilizing genomic and molecular tools to answer long-standing evolutionary questions about the origins of multicellular complexity. Earlier this year, his group revealed how the rove beetle gland has been reprogrammed during evolution to produce new chemical compounds, allowing these beetles to forge new ecological interactions with other species, including symbioses with ants.

"Understanding the mechanistic basis for evolutionary novelty has been a long-standing problem in biology, and Joe is leading the way to unraveling how to study this problem and already getting rigorous answers," says Paul Sternberg, Bren Professor of Biology and William K. Bowes Jr. Leadership Chair of the Division of Biology and Biological Engineering. "Joe's success, and frankly, his genius, is based on his stunning combination of deep biological understanding, effective use of modern laboratory tools and old-fashioned fieldwork, all passionately applied to understand his favorite beetles and how they engage with ant colonies."

Parker's research is highly integrative, involving studies of rove beetle genomes, cell types, chemical ecology, behavior, and evolutionary history. Recently, his group has begun exploring how the rove beetle brain allows the insects to interact adaptively with ants, and how changes in the beetles' neural circuits underlie the evolution of socially complex symbiotic behaviors inside ant colonies. By studying different facets of the rove beetles' biology, Parker's work is shedding light on the evolutionary processes that underpin Earth's biosphere, including factors that cause different species to begin interacting with each other, and the phenomena that drive organisms to become specialized with other species.

Parker is also an affiliated faculty member with the Tianqiao and Chrissy Chen Institute for Neuroscience at Caltech. He received a bachelor's degree in 2001 from Imperial College London and a PhD in 2005 from the University of Cambridge/MRC Laboratory of Molecular Biology. He was a postdoctoral fellow at Columbia University from 2008 to 2016 prior to joining the Caltech faculty in 2017. He is also a research associate in the Division of Invertebrate Zoology at the American Museum of Natural History.

Parker received a National Institutes of Health BRAIN Grant and a Sloan Research Fellowship in 2020. He was named a Pew Biomedical Scholar in 2022.

Parker began his lifelong fascination with insects at the age of 7 while growing up in Swansea, Wales.

"I'm stunned and still trying to process this," says Parker of the MacArthur Fellowship. "To be recognized in this way is just the most profound honor. I'm still that 7-year-old kid."