Traditionally, biologists and ecologists study microbes and hosts separately. And, it’s only recently that 'Hologenomics' emerged as a discipline with a holistic perspective. Rob Dunn's work in this field influenced his three best-selling books, Delicious, The Wildlife Of Our Bodies, and Never Home Alone.

In this episode, Rob takes us on a scientific taste adventure. In his use of “hologenomics” perspectives, he explains why humans crave flavors that cannot be explained by their nutritional needs, and how they may have been influenced by evolutionary development. 

Tune in to hear Greg and Rob talk about anthropology, history, and evolutionary biology, including the extinction of megafauna and the influence of plants and animals on the human palate.

How Hologenomics combines different fields of sciences in its applications

Historically people who studied microbes, so things that are invisible without a microscope and people who studied animals, were in different departments. And even if they were studying the same interaction, they would study it from totally different perspectives. And so, if I studied skin microbes, I'd focus on them. And if you studied skin, you would focus on the human. And so, Hologenomics is an approach where you study all of that at the same time. And so, a human and its microbes, a goat and its microbes, a Gobi fish and its microbes. And this is made possible partly because the tools are now the same tools. I can study your genes and your microbes' genes at the same time. And so, it's a field that recognizes the value of whole-ism, but at the same time, reflects changes in how we study things.

Thoughts on co-evolutionary process of plants and animals

So, some species— well, some parts of species like fruits, they have evolved to have chemicals that appeal to the taste and the smell of the specific animals they want to eat them. And then, by the flip side of that is that, many sorts of the leaves of plants, very often, produce chemicals that relate to bad tastes in the animals they don't want to eat them. And so, there's this kind of culinary dance between plants and animals and between lots of organisms. That’s super fascinating and hinges on that bite, you know, that we all do that, animals do.

Why do you think science hasn't really paid a lot of attention to things like taste?

Because we're just still so early in science, but I think the second thing is that often we don't have the right tool yet. I think taste receptors are like that. That, for a long time, it was really hard. Even if you knew what the gene might be for a taste receptor, to then compare that from one species to another, it was expensive. Maybe if you'd looked at sweet taste receptors in humans, you could also look at them in rats, and then your Ph.D. was over. Now, that's cheap and easy. Easy is too strong. It's cheap and feasible. And so that's the other part, is that the technology that you need is sometimes lagging. And I think with tastes, that's been one of the pieces. Now we have genetic technologies that allow us not only this study tastes in humans, But also to compare it.

00:00:57 What is hologenomics?

00:02:13 Hologenomics and ecology as fields that help us understand the world better

00:03:47 Rob Dunn’s early work as an intern

00:07:12 What's so different about the book Delicious and did you take unique approaches to animal behavioral science?

00:11:45 Why bacteria in cadavers secrete weird odors

00:13:00 How our taste palette’s affected by our evolution

00:15:00 Stoichiometry, taste palettes and signaling what the body needs

00:21:24 Bias on technology and detecting existing conditions only

00:23:09 Gap between studying known conditions vs. studying different aspects of biology to add context on these known diseases

00:24:25 Will exposing doctors to evolutionary theories or studies create a different framework for looking at the human body?

00:26:33 Understanding Covid-19 and why looking at any bacteria, as bad bacteria may not be the best perspective

00:31:31 Wildlife of our bodies and fecal transplants

00:34:00 Fermented foods and garden of microbes

00:35:39 Evolution of fruit trees and the animals that consume them

00:37:53 Flavor of plants and animals and how they serve as chemical defense

00:39:34 Spices, microbial components, human, and plant evolution

00:40:19 Why do humans have to learn how to like certain tastes?

00:47:44 How do you fix what's wrong with science and thoughts on rigorous testing

00:53:51 Rob Dunn’s next book

Guest Profile

• Rob Dunn’s Adacemic Profile at NC State University
• Rob Dunn on LinkedIn
• Rob Dunn on Twitter

His Work

• Rob Dunn Lab
• Rob Dunn on Google Scholar
• Rob Dunn’s Articles on TED
• Rob Dunn Podcast Episodes on Science Friday
• A Natural History of the Future: What the Laws of Biology Tell Us about the Destiny of the Human Species
• Delicious: The Evolution of Flavor and How It Made Us Human
• Never Home Alone: From Microbes to Millipedes, Camel Crickets, and Honeybees, the Natural History of Where We Live
• The Man Who Touched His Own Heart: True Tales of Science, Surgery, and Mystery
• The Wild Life of Our Bodies: Predators, Parasites, and Partners That Shape Who We Are Today
• Every Living Thing: Man's Obsessive Quest to Catalog Life, from Nanobacteria to New Monkeys