Friday, December 22, 2017

"Dinner With Darwin: Food, Drink, and Evolution"

Jonathan Silvertown, in his recently published book Dinner with Darwin, presents a tour of humanity from prehistory to recent times. He explains what hominids -- both humans and pre-humans -- ate while evolution, natural selection, and artificial selection were combining to create both our species and the many species of plants, animals, and even micro-organisms that we gather and/or cultivate for food.

Darwin's name in the title isn't just there because the publisher thought it would boost the book's sales (a temptation many publishers don't resist). There are quite a few references to Darwin's various publications, noting from the start of the book that Darwin's concept, natural selection, is "the process that not only produced our food but also produced us. Our relationships with food demonstrate evolution in ourselves and in what we eat." (p. 3)

The origins of cooking, the processes by which a number of pre-human species developed methods of improving food and crops, and how cooked food changed early hominids is the concern of one early chapter in the book. I was familiar with some of the details Silvertown presents, because of Richard Wrangham's important book Catching Fire: How Cooking Made Us Human (2009). The evolution of cooking and its effect on humans took place mainly before humans migrated out of Africa.

In the second chapter, I found material that I haven't read in other books. Silvertown continues his prehistoric coverage by tracing a migration that began around 72,000 years ago. Humans slowly proceeded from the horn of Africa along the south-west coast of the Arabian peninsula, around the coast of Southeast Asia, up the coast of China, across the Bering Strait, and down the West Coast of the Americas until humans reached Patagonia and Tierra del Fuego approximately 10,000 years ago. Generation by generation, what did they eat? Shellfish, especially mussels: "a food almost as timeless as mother's milk." (p. 29) Silvertown describes the mountains of seashells along the route of human migration, eventually quoting Darwin's description of the Tierra del Fuego natives whom he encountered when the Beagle visited there in 1832: "Whenever it is low water, winter of summer, night or day, they must rise to pick shellfish from the rocks." (p. 34) Of course I enjoyed this observation as I was recently in Tierra del Fuego -- though very sadly, the natives Darwin met were the victims of genocide by settlers later in the 19th century, and none of them are still present.

Throughout the book, Silvertown emphasizes not just what is known, but how scientists know it. For example, the history of grain and bread is reflected in a number of Egyptian tombs, in Mesopotamian clay tablets recording a large number of types of bread and flour and cooking techniques, and other evidence from archaeological sites. He also explains why agriculture began in the Fertile Crescent (the modern Middle East): the region was particularly good for the development of so many cultivated crops because its annually varying climate fosters annual plants which set abundant, large seeds at a particular time, and these plants, because of their adaptation to the varying climate, are relatively easy to change by artificial selection. 

Other scientific evidence of evolution in hominids and food species appears throughout the book. Silvertown explains how material left on human teeth found in ancient sites can show just what foods the teeth-owners were consuming, because the build-up of dental plaque can be analyzed by recently developed methods. In the chapter on wine, beer, and the processes of fermentation, Silvertown traces the evolution of the microbes that humans have domesticated in order to create alcoholic beverages and other fermented foods. He describes how naturally occurring toxins in herbs and vegetables evolved by co-evolution with animal and insect predators, and how these were tamed by human agricultural selection, by cooking, and by other food processing. There's also information about how early evolution enabled human sensory organs to detect poisons, and thus allowed us to consume -- and even to enjoy -- nutritious though poisonous plants. Many details about chemical receptors on the tongue, in the nasal apparatus, and elsewhere in the human body are very intriguing. The final chapter is a defense of GMO development, which the author sees as another extension of human ingenuity in evolving crop improvement.

Fascinating maps show the migrations and other information about human history. Here is an example:
Map from Dinner with Darwin, p. 10.
Ma means million of years ago.
Ka means thousands of years ago.
Unlike several of the authors I've recently read on food history and human evolution, Silvertown is a scientist, not a journalist -- he is a professor of evolutionary ecology at the University of Edinburgh. The science in the book is presented effectively for a non-technical reader, but the author does not talk down to the reader. I admire his approach to his topic: he finds out things by looking at scientific studies, not by interviewing people. I especially appreciate that he isn't a name-dropper! In sum, I found his book both entertaining and very enlightening.

5 comments:

Beth F said...

Sounds like a good introduction for those new to the interplay between diet and human evolution.

rhapsodyinbooks said...

This sounds great! Who would have thought of such an idea for a book about food? Thanks for bringing it to our attention!

Deb in Hawaii said...

It sounds like a fascinating book--I'll look for it!

bermudaonion said...

Wow! This sounds fascinating!

Les in Oregon said...

This really sounds like an interesting book! I think my husband (who enjoys reading and writing about this sort of thing) might enjoy it, as well. Maybe a late Christmas gift? :)