Interview with Dr. Bernard Crespi

Professor & Tier 1 Canada Research Chair, Department of Biological Sciences

Molecular Phylogenetics

Genes and environments that create risk for mental disorders can be investigated in terms of evolved adaptations that have become dysregulated. Dr. Crespi’s research program integrates evolutionary biology and genetics with aspects of human health and disease. Ultimately, his work will advance our understanding of brain function and it will lay the foundation for developing new diagnostics and therapeutics for tempering mental illnesses.

What early life experiences influenced you to become a scientist?
I always loved running around looking at bugs and birds, identifying animals and reading all the books in the library about birds and insects. I knew from how much I enjoyed being outside that I wanted to be a biologist.

What is the most satisfying part of your research?
Finding out something about the world that was never known before, even if it is something small. You can end up changing how other people think. To have some impact on science, knowing that you have made a difference.

What is the overarching goal of your research program?
It involves integrating evolutionary concepts and tools toward understanding humans and to apply the understanding to improve human well-being including mental and physical health. Sometimes this field is called evolutionary medicine.

What research is your lab group doing right now?
We have projects aimed at understanding the autism spectrum in relation to typical people. There is no boundary there, it is continuous variation. We want to understand these disorders in terms of which adaptive functions of humans have become dysregulated because these are evolved adaptations.  We put forth a rather radical and novel theory, the “diametric theory,” in which humans are on a continuous spectrum where the two extremes are autism and schizophrenia.

We are looking at this from a DNA perspective as well as a hormonal one. We also examine the roles of genetic conflict in these disorders. These conflicts are related to variations among humans, and health and disease.

Why is your diametric theory controversial?
The relationship between autism and schizophrenia has been controversial dating back to the 1940s. Before that time, when a child had a mental problem it would be called childhood schizophrenia. Then, syndromes such as autism and Asperger’s were described. Researchers had to argue strongly that autism was distinct from childhood schizophrenia.

Our work says that some mental disorders can be opposite to others, and this idea was not out there before. It takes a very long time to change views in traditional disciplines like psychiatry, but we are seeing more and more frequent studies that test and support our theory.

How has your own research progressed since you first proposed the diametric theory in 2008?
We took all the data that exists on a genetic factor called copy number variants, which involve big chunks of DNA that are deleted or duplicated in the genome. Human medical geneticists worked on these for about a decade, but no one put it all together, let alone looked at that data in terms of our theory. Our results showed opposite patterns in copy number variants for schizophrenia versus autism.

On the psychological side, some humans show a trait that is underdeveloped in autism, i.e. the conception of minds beyond their own. In contrast, those with schizophrenia often experience paranoia, i.e. delusions that other minds are focused upon them. We wanted to examine the regular population to look for the same pattern.

What other psychiatric disorders have been investigated from an evolutionary perspective?
The field of evolutionary psychiatry has been around for a long time. It has been very speculative. Many disorders overlap, like schizophrenia, major depression, bipolar, borderline, and others. The theory applies to various disorders, but we focus on schizophrenia because there has been more research conducted on it.

There is now work being done at the interface between evolutionary biology and psychology for various disorders, such as depression and anxiety.

Have any of your previous students crossed over from evolutionary biology to psychiatry?
Not yet, but one of my students is currently teaching a course about evolutionary biology and psychiatry. There is virtually no evolutionary biology in med school curricula. Very few have crossed over because you need extensive training in both. I teach a 4th-year course in evolutionary health and disease – many of the students in it are pre-med. I think this is the way that we are going to have some impact on the medical sciences. The students love the course content and I think the concepts of evolutionary biology will make their way into psychiatry, oncology, and other medical fields.

What do you think will be the next big thing in your field?
The next big thing will come from a better understanding of how the brain works. It is such a massive unknown.  This insight may come from new methodology to examine what's going on in the brain; it could also come from computing artificial intelligence and machine learning.

The next 20 years should be very exciting. I'm not sure how rapidly evolutionary biology will permeate the field...that will depend on training of undergraduates and medical students. I've seen it from the beginning. I was at Michigan as a grad student when the field of evolutionary medicine was created about 30 years ago. The field now has a few journals and it is growing rapidly.

What is the funding landscape like for your particular research program?
The challenge with my research is that it is situated between discovery and medical-based research. This means that my program can be considered to be 'in between' NSERC and CIHR funding.  I consider it to be basic, discovery research with especially strong health implications.

Beyond your work, what contemporary scientific issue concerns you the most and needs more attention?
I would like to see more training for elementary and high school students in scientific methods and scientific thinking. We have 4th-year undergraduates who have never written anything like a scientific paper before. The process of scientific writing is so fundamental: gathering evidence, thinking about the statistics of it, the process of dealing with scientific evidence and evaluating it. Students must be able to think about questions analytically and scientifically. I think that this is especially important because the world is becoming increasingly more technological, so critical thinking skills need to be taught early on. It works so much better when they learn these skills when they are young.


Read more: Dr. Crespi’s profile on the Biological Sciences website, the Canada Research Chair website, and the Featured Researchers page.

Interview by Jacqueline Watson with Theresa Kitos