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During a tour of the Marine Biological Laboratory in Woods Hole, Massachusetts, Corey Allard noticed something strange: fish using six leg-like appendages to "walk" around the bottom of their tank.

Allard was intrigued to learn that scientists suspect the appendages are sensory organs that help the fish—called sea robins—feel around in the sand for prey. His intrigue deepened upon discovering that almost nothing was known about sea robins beyond a couple of papers from the 1970s.

Soon, he was studying the bizarre-looking fish.

The encounter started Allard on a research journey that culminated in becoming an assistant professor of cell biology in the Blavatnik Institute at Harvard Medical School. Allard, who launched his lab last fall, takes a curiosity-driven approach to studying a range of species, seeking to reveal basic biological principles—some of which may ultimately have applications for medicine or industry.

In a conversation with Harvard Medicine News, Allard shared more about the value of focusing on unusual organisms, why he's excited to join the faculty of a medical school, and what the field might lose as federal research funding—which has been a source of support for his research—faces an increasingly uncertain future.

What do you study, and why?

We study species that have some unusual trait or behavior—something that causes us to pause and wonder how, exactly, it works. Something that challenges our assumptions of biology. Then we try to learn from that species, often in terms of molecules and cells. We ask questions like how the species evolved that trait or behavior and how it functions. In this way, we can get at bigger questions related to neuroscience, evolution, and comparative biology. The long-term goal is to deepen our knowledge of basic biology in ways that help us understand disease and develop new treatments.

Famous physiologist August Krogh developed a principle stating that for any particular scientific question there is an organism ideally suited to studying it. We flip Krogh's principle on its head by making the case that most unusual organisms have something important to teach us.

We have studied lots of unusual species, including cephalopods, sea robins, and more recently, a remarkable lineage of sea slugs. In each case, we've identified a species that we think is useful for asking a question that couldn't be asked with more conventional research organisms such as mice or zebrafish.

How did you become interested in unusual animals?

I've always been fascinated by animals and how they work, but I didn't realize studying animals could be a career until college. As an undergraduate, I volunteered in a lab that studied Antarctic icefish, which are fish that don't have red blood cells—they basically have evolved anemia. We were using the fish to identify genes involved in red blood cell formation. Through this research, I became interested in the strategy of comparative biology and using species with unusual traits to understand biology and medicine—basically looking at extremes or exceptions.

What topics can you study by looking at extremes and exceptions?

There are a range of them. For example, as a postdoctoral fellow in the lab of Nicholas Bellono at Harvard University, I studied the organization and function of the nervous system in octopus and squid. These organisms have sophisticated nervous systems that support complex behaviors but are organized in a radically different way than other species—including humans—and thus challenge our understanding of how nervous systems work.

We focused on sensory systems, specifically the sucker cups that octopus and squid have on their arms and tentacles. People have known about sucker cups for a long time, but nobody understood how they worked in terms of sensory function. We asked basic questions, such as what are the ? How are these cells ? How do sucker cups mediate behaviors unique to cephalopods?

Using cephalopods to learn about the basic function of nervous systems aligns with our main goal: to discover fundamental principles that can be applied broadly to many species. In making comparisons between species, we can discover core principles that operate across systems. This is the kind of information that can end up being translated into medicine or industry.

What are you learning in your research on sea robins?

Sea robins are a really cool example of a novel trait in evolution. Where novel traits come from has long been a major question in biology—but one that's hard to study because there aren't many good examples, especially in vertebrates. Sea robins turned out to be a great species for addressing this question.

We want to understand everything there is to know about sea robin "legs," including what they are, , how they develop, and . Once a species evolves a new sensory organ, a big mystery is how that organ is integrated into the nervous system and controlled. We've figured out that sea robins have additional regions in their brain and spinal cord that are dedicated to controlling and processing sensory information from their legs.

This is a great example of research that could only be done with a specific species. We had to study sea robins to investigate how a new sensory organ evolves.

What techniques do you use in your research?

We don't use any one technique. Our curiosity often leads us in unusual directions, and we have to adapt, so we try to use whatever technique is called for, whether that's RNA sequencing, bioinformatics, histology, microscopy, or electrophysiology. Plus, because our species aren't model organisms, they don't have extensive toolkits, so we have to develop our own. There is always some tool that we either have to learn or work with collaborators to do. In fact, virtually every project we do is collaborative in some way.

For example, we're collaborating with Rachel Wolfson's lab in our department on our sea robin project. My lab has discovered that sea robins have massive spinal ganglia—clusters of sensory neurons—that extend to their legs. We think these spinal ganglia are one of the special parts of their nervous system. Rachel's lab studies similar questions of internal sensation in mice, so we've been working together to understand the function and evolution of sensory cells—why a fish might be this way and a mouse might be that way.

How did you end up at a medical school?

In a lot of ways, I'm probably an unusual fit for a medical school. What it comes down to is that we're interested in the basic functions of cells and molecules in all these different contexts. When I started thinking about the types of scientists I want to have right down the hall, I was excited about being near people who think deeply about these topics and who are experts in molecules and cells and the powerful techniques like proteomics that we can use to study them.

From that perspective, even though we think about these questions in very different ways, people in my lab have a lot in common with other folks at HMS and in the Department of Cell Biology.

What other projects are you working on?

One of my main projects right now is on two amazing lineages of sea slugs. Both steal cell parts from other species and use the parts in their own bodies.

One slug eats specific algae and steals the algae's chloroplasts—the organelles green plants use to produce food via photosynthesis. Then, instead of digesting the chloroplasts, the slug puts them inside its own cells and uses them to photosynthesize.

The other slug eats sea anemones and steals organelles responsible for stinging. The slug incorporates the stinging organelles into its cells, which gives it the ability to sting.

We want to understand the basic biology of how slugs steal, maintain, and use organelles from other species. Also, if we can learn how to engineer other types of cells to do this in the lab, there could be medical or industrial applications.

That's super-interesting—it sounds like a video game.

Exactly. And that's the kind of stuff I get excited about.

We have a few other projects that are variations on the theme of studying novel traits and behaviors, but it's still early days, so we don't know how they'll pan out. There is a lot more to come.

Why is federal funding so essential in your field?

I often hear that if our science was important, we'd be able to get a company to pay for it—which is based on the idea that all important research is directly related to developing something that will be profitable in the short term, like a new drug. But we've seen time and time again that many of the biggest breakthroughs in science have come from people doing basic research that didn't initially have a clear immediate application.

This kind of research, which includes the research in my lab, requires federal support. It is a type of research that we critically need and that I'm afraid we'll lose if federal funding disappears.