Welcome to the Johnson Lab


Research in my lab focuses on understanding evolutionary diversification in the wild.  We ask how biological diversity arises in response to varying ecological conditions, and explore what this can tell us about patterns of life on earth today. Work in my lab combines field and laboratory approaches with genetic data in an effort to understand evolutionary diversification from multiple perspectives along the genotype-phenotype axis.  We study a variety of important traits including life histories, morphology, and behavior.  Several of our projects combine problems in evolutionary and behavioral ecology with historical perspectives offered by phylogeography and molecular systematics. The availability of whole genome data (ddRADseq) has opened up several new possibilities to address our most fundamental research problems. This integrative approach allows us to work comfortably at the interface of ecology and evolution.

Research Highlight: “Not always best being biggest fish in the stream, BYU study finds.”




Our work also takes us to some pretty great places, mostly focusing on New World freshwater fishes. We currently have projects in Central America and Mexico, in Patagonia (southern Chile and Argentina), in Australia, and in the North American Great Basin. Our lab is driven by basic research questions.  Currently these questions focus on the repeatability of speciation, the evolution of personality, the nature of character displacement when three or more species interact, and the causes and consequences of sexual mimicry.  Some of our projects also have specific conservation implications (e.g. protecting rare desert fishes in the U.S. and Mexico, delineating conservation regions in Patagonia, understanding how unmetabolized drugs in human wastewater affects native fish, etc.). Not surprisingly, we are actively involved with government agencies and NGO’s whose goals are to preserve rare species and to protect critical habitats. Basic or applied, what binds our projects together is that they each promise to provide new understanding into the remarkable diversity of life on earth that we see today. I invite you to look around on our web page to learn more about what we are doing, and to explore opportunities to get involved with this exciting work.

Jerald B. Johnson
Professor of Biology
Assistant Curator of Fishes