Catherine (Katie) Peichel is an evolutionary geneticist who pioneered the development of stickleback fish as a model system to study the genetic basis of adaptation, speciation, and sex chromosome evolution. She is originally from southern California and did her undergraduate studies from 1987-1991 at the University of California, Berkeley, where she fell in love with the power and elegance of Mendelian genetics. During her PhD at Princeton University from 1991-1998, she applied the power of genetics to understand how organisms develop. As a postdoctoral fellow from 1998-2002 at Stanford University, she and David Kingsley developed the threespine stickleback fish into a “supermodel” in evolutionary genetics. From 2003-2016, she led a research group at the Fred Hutchinson Cancer Research Center. After 13 years in Seattle, she moved her lab, a dog, and 4000 sticklebacks to Switzerland to become Head of the Division of Evolutionary Ecology at the University of Bern. She loves to share her knowledge of genetics and is an author on the undergraduate textbook Introduction to Genetic Analysis. She received a Guggenheim Fellowship in 2013, was President of the American Genetic Association in 2015, and was elected to the American Academy of Arts and Sciences in 2020 and the National Academy of Sciences in 2023.

Research Interests

My research group has made major contributions to understanding fundamental questions in evolutionary biology, including (1) how and why do sex chromosomes evolve?; (2) what is the genetic and neural basis of behavioral evolution?; and (3) what is the genetic and genomic basis of adaptation and speciation? Our work on the diversity of young sex chromosomes in sticklebacks contributed to a paradigm shift from studying old and degenerate sex chromosomes, to using young sex chromosomes like those in sticklebacks to understand how and why these unique regions of the genome evolve. We further demonstrated that the evolution of a new sex chromosome in one species contributed to the evolution of behavioral isolation between species. Similarly, our work to identify the genetic architecture of morphological and behavioral traits that underlie adaptation to divergent habitats has also revealed how these genetic changes contribute to reproductive isolation between young species. Our current research focuses on how the genome itself evolves, and how genome evolution contributes to adaptation and speciation. In all of these research areas, we combine rigorous genetic and genomic approaches in the lab with behavioral, evolutionary and ecological studies in the field to understand both the proximate mechanisms (i.e. molecular, developmental, neural, genetic and genomic) and the ultimate causes (i.e. selective forces) that lead to the spectacular phenotypic diversity we observe in nature.

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Primary Section

Section 27: Evolutionary Biology