“We’ve had to be able to startle—to escape from stimuli—through the whole history of evolutionary time. It’s a really interesting question to figure out how we do that.”
Most scientists study animals while they’re stationary. It’s a lot easier that way. But Melina Hale studies fish in motion. She wants to find out what’s happening inside their brains—and what signals are traveling through their system from brain to fin and fin to brain—that allow movement to occur.
You wouldn’t necessarily think it, but the brain of a fish and the brain of a person have a lot in common. What the fish contemplates may be different from what we think about, but how we conduct the process of thinking is similar. So when Melina figured out how the startle reflex works in fish and which neurons control it, that also explained how humans startle. “These little three-millimeter fish provide a window into the brain that we couldn’t get at in any other way,” says Melina.
When Melina’s sons were little, she would make guesses about what was happening inside their brains. “It was fascinating to watch the changes and how they were able to move,” Melina says. “From crawling to walking, I was associating it with what was happening in their spinal cords or neural circuitry.”
How to Find Out More
A lot of other projects are underway at Melina’s lab at the University of Chicago, and you can learn about those here. She also is a research fellow at the university’s Marine Biology Laboratory in Woods Hole, Massachusetts—which is a cool place to know about in and of itself.
This article explains more about the breakthrough realization that the fins of fish have sensors that are sending signals to the brain and not just vice versa—something Melina talks about in the episode.
This video from the National Science Foundation provides a nice overview of Melina’s work, and how, as the Foundation puts it, “one tiny fish can teach us big ideas about how the brain’s circuitry works.”
Aquariums stacked up in Melina Hale’s laboratory. They’re filled not only with larval zebra fish; graduate students study biomechanics of various fish species.
Laboratories are more than just centrifuges, test tubes and ah-ha moments. Here’s one of the workspaces in Melina’s lab.
Melina and her team of grad students studied how the African Lungfish walks on its hind limbs. This species is likely related to the very first fish-like creatures that crawled out of the water and started to live on land. (Our ancestor!) This article in Scientific American explains more about that research.