Micah G. Freedman

Current Position: NSF Postdoctoral Fellow, University of Chicago

Previously: Ph.D.: Population Biology, UC Davis

About Me

I am currently an NSF Postdoctoral Research Fellow in Biology in the Kronforst Lab at the University of Chicago. I am also supervised by Dr. Riccardo Papa at the University of Puerto Rico, Río Piedras.

I completed my Ph.D. in Population Biology at UC Davis and was advised by Santiago Ramírez and Sharon Strauss.

Previously I studied Entomology at Cornell University and worked for The Ecology of Bird Loss Project in Guam and the Northern Mariana Islands.

Image: Phacelia crenulata and a red spider mite, photographed in Imperial County, CA

Research

Current projects

(1) Monarch migration: I am working on an NSF-funded project to understand the genetic basis of seasonal migration in monarch butterflies.

(2) Monarch sequestration biology: For my NSF PRFB, I am studying the evolution of cardenolide insensitivity and sequestration in monarchs. I am using rearing experiments and genome editing techniques to understand how monarchs sequester cardenolides.

(3) Miscellaneous ongoing projects: (1) Evolution of floral scent emission in Abronia and its close allies, in collaboration with Eric LoPresti and others. (2) Loss of anti-herbivore defenses in plants from the California Channel Islands. (3) Correlated evolution of caterpillar coloration and ecology, with Moria Robinson, Marjorie Weber, and Sharon Strauss

Image: Narrowleaf milkweed, A. fascicularis, a representative of the Incarnatae clade within Asclepias, contains very low concentrations of cardenolides but has high production of latex.

I am an evolutionary biologist and chemical ecologist. Much of my research has focused on monarch butterflies and their interactions with milkweed host plants, but I am broadly interested in the process of adaptation and methods for detecting natural selection.

Image: Heteromeles arbutifolia (Toyon), a common chaparral shrub in California. Plant secondary chemistry differs between populations on the California mainland and the nearby Channel Islands.

I am especially interested in the recent global range expansion of the monarch butterfly. Over recent evolutionary history, monarchs have expanded across the Pacific, the Atlantic, and into the Caribbean and South America, where they form non-migratory, year-round breeding populations.

Image: Monarchs from Puerto Rico (left) and North America (right) reared under common greenhouse conditions

My doctoral research focused on contemporary evolution in recently-established monarch populations around the world. I use a combination of population genetics, greenhouse experiments, and museum collections to test evolutionary hypotheses.

Image: A monarch butterfly nectaring on A. curassavica in Guam. Monarchs were first recorded in Guam in 1887.

Some of the tools I use in my research:

Population genetics

Monarchs are originally from Central and North America but can now be found around the world. When and why did this range expansion occur? How are these populations related to one another?

Chemical ecology

Monarchs feed on milkweed plants as caterpillars. How do cardenolides (toxic secondary compounds) produced by milkweeds influence monarchs and their interactions with natural enemies?