Illustration by Mary Crooks
  • Steven is a neurobiologist and chair of the neurobiology department at the University of Massachusetts Medical School in Worcester, Massachusetts.

    He is currently researching the biological basis for the monarch butterfly’s migration.


    Steven says he has always had a “lifelong interest and curiosity about how things work in the world, particularly moths and butterflies and how their biology is affected by the environment.”

    A formative experience occurred when Steven was nine years old. He placed several female silk moths inside his screen porch one summer evening, knowing that the insects emit pheromones to attract males as the sun rises in the morning. Steven woke early to witness the sky filled with moths outside his screened porch.

    “That was an impression that said, ‘wow, the environment and time of day really have a pretty important influence on the biology of these animals,’” he says.

    Steven’s father was a veterinarian, while his brother is currently a physician in Colorado. Steven worked at Massachusetts General Hospital for 25 years before switching careers and taking over the University of Massachusetts Medical School’s neurobiology department seven years ago.


    “There’s nothing cooler than discovering something no one has ever discovered before.”


    “Science can be very tedious. It can be a lot of work. It can consume your thoughts to the point that when I’m driving to work I can drive past the exit on the highway that gets me to where the research building is where my laboratory is housed.”


    Steven says that geography used to be boundaries, but now that concept is changing due to technology. “Geography from the vantage point of scientific discourse, scientific discovery, has become very blurred, because information transfer and the way that people access information is almost immediate now from just about any corner of the world.”


    Steven says that geography is very important while researching the migration of monarch butterflies. “Obviously, when you are studying an animal that migrates, you have to think about the geographical barriers that are going to be there such as bodies of water, mountain ranges, and other sorts of things,” he says.

    While studying the monarch butterfly’s migration, Steven says that he and other scientists are trying to determine “what is geographically unique” about the insects’ overwintering sites.


    “I think the best way to learn about nature is to be outside experiencing it, seeing what birds are around and looking at the local habitat. What plants are there? What flowers are in blossom at that particular time of year in that particular area?”


    Steven suggests that students or families interested in learning more about the migrations of the monarch butterfly should check out Monarch Watch and Journey North.

    Neurobiologist: Dr. Steven Reppert

    Stephen Reppert is a neuroscientist.

  • Term Part of Speech Definition Encyclopedic Entry
    biology Noun

    study of living things.

    context Noun

    set of facts having to do with a specific event or situation.

    discourse Noun

    conversation or discussion.

    environment Noun

    conditions that surround and influence an organism or community.

    habitat Noun

    environment where an organism lives throughout the year or for shorter periods of time.

    Encyclopedic Entry: habitat
    migration Noun

    movement of a group of people or animals from one place to another.

    monarch butterfly Noun

    insect native to North America.

    moth Noun

    flying insect.

    neurobiologist Noun

    person who studies chemical reactions in the brain.

    overwintering site Noun

    winter destination of a migrating animal.

    pheromone Noun

    substance released by an animal that influences the behavior of other animals of the same species.

    physician Noun

    medical doctor.

    technology Noun

    the science of using tools and complex machines to make human life easier or more profitable.

    veterinarian Noun

    person who studies the health of animals.