Show 1295: How Delicious Flavors Shape Human Behavior

This week on our nationally syndicated radio show, our topic is evolution and the role of delicious flavors. We talk with Dr. Rob Dunn, ecologist and evolutionary biologist, about how the search for food with delicious flavors as well as high nutrient content might have shaped our behavior as we evolved.

How Humans Define Delicious Flavors:

If you think about your favorite flavors, you’ll probably be able to conjure up quite a range, from mint-chocolate chip ice cream to a seared steak or miso soup with mushrooms. Taking culture into account expands the range even more. For example, most Americans would not think of grasshoppers as delicious, but in Oaxaca, Mexico, they are a delicacy. When we lived there, we found them very tasty.

Rob Dunn suggests that the search for delicious foods has encouraged us to eat things that can help us survive and thrive. And we are not alone. Animals and birds have evolved taste perception that is well suited to their ecological niches. Moreover, primates are likely to share these preferences with others in their group. Dr. Dunn describes how chimpanzees in one rainforest location use tools to acquire the ants they like to eat. In neighboring regions, chimps eat different ants and use different tools to access them. Each group has its own culinary culture, a term we are more likely to associate with humans than with chimps.

The Science of Taste:

Scientists have not paid a great deal of attention to taste, partly because it is difficult to study. It is a complex sense that draws on the sense of smell in addition to the five flavors that our taste buds register. However, the research needs to be interdisciplinary, and that can be a challenge.

How Delicious Flavors at Dinner Make Us Human:

When you find something with especially delicious flavors, whether it is aged cheese or a great cup of coffee, you may want to share it with your family members and friends. When we share food, it encourages the release of oxytocin, a hormone associated with social bonding. While animals can share, and some do, humans are especially good at this. Dinner parties and village festivals, Mardi Gras and Thanksgiving dinner are all great examples of the cultural overlay that humans have added to the act of sharing food. Rob Dunn co-authored Delicious with his wife, medical anthropologist Monica Sanchez.

Did Humans Hunt the Tastiest Species to Extinction?

Quite a number of large mammals once hunted by early humans became extinct. Did people hunt them to extinction? We can't go back in time to study this process as it happened. Consequently, it is a contentious issue. But there is certainly evidence that points in that direction. Wooly mammoths, for example, may just have been too tasty, even though they were doubtless dangerous to hunt.

Future Evolution:

In A Natural History of the Future: What the Laws of Biology Tell Us About the Destiny of the Human Species, Dr. Dunn suggests that trying to control nature is fruitless. His metaphor is the Mississippi River, which regularly washes over the levies built to contain it and floods communities on its banks. Understanding evolution and the law of natural selection is key to human health and survival.

Natural Selection in Action:

Understanding natural selection is crucial when it comes to microbial resistance to antibiotics. In one experiment Dr. Dunn describes, the researchers (including Michael Baym and Roy Kishony and others) set up a giant petri dish (Science, Sep. 9, 2016).  They called it the Microbial Evolution and Growth Arena (MEGA) plate and it had increasingly concentrated levels of antibiotics from the edges to the center. Bacteria without resistance to these antibiotics were introduced at the edge of the MEGA plate. In less than two weeks, they had evolved resistance to highly toxic concentrations of the antibiotic. That is the power of evolution! The question is whether we can learn to appreciate, respect and potentially harness that power for our own future well-being.

This Week's Guest:

Rob Dunn is an ecologist and evolutionary biologist, focusing on the biodiversity of humans. He is the William Neal Reynolds Distinguished Professor in the Department of Applied Ecology at North Carolina State University and in the Center for Evolutionary Hologenomics at the University of Copenhagen. Rob Dunn is the author of several books, including Delicious: The Evolution of Flavor and How It Made Us Human (with Monica Sanchez) and
A Natural History of the Future: What the Laws of Biology Tell Us About the Destiny of the Human Species. The photograph of Rob Dunn is by Amanda Ward.