Well, for my scientific research, one of the things I worked on was biological networks. You have all heard about Charles Darwin and the “Tree of Life”, the idea that all organisms are descended from ancestors, with modification. That is, a family tree (of people) becomes a bigger, and older, tree of all organisms, if we go back far enough in time. Well, this is only partly true, because there are all sorts of genetic inter-connections among those branches, so that it is actually a “Network of Life”.
I was one of the early people championing this idea, back 20 years ago. The book that I received is called: The Network of Life: a New View of Evolution, by David P. Mindell (June 2024. Princeton University Press). So, let’s look at this book here, and some ideas it covers related to the effects of alcohol on people. I need to present some background first, and then move on to the alcohol effects.
The network idea is that species share genetic material, via a process called horizontal evolution, so that evolution is actually a web of shared genealogy, instead of just from ancestor to descendant. Species are thus more interconnected than previously thought. Life is not a tree but a network (see the next figure). The complex example of our own history (Homo sapiens) is shown in the network diagram below (taken from Mindell’s book).
To establish my bona fides, at the end of this post I have listed a few of my professional publications related to this topic of evolutionary networks, including the introductory book that I wrote (Introduction to Phylogenetic Networks). My previous blog (2012—2020) was also on this topic: The Genealogical World of Phylogenetic Networks. *
My connection to this new book (and why I got a free copy) is indicated in the Preface: “I am enormously grateful to colleagues who read sections of the full draft of the book. Their insights, patience, and thoughtful commentary improved the book a great deal. This includes Ford Doolittle, Axel Meyer, David Morrison, Greg Gibson, James McInerney, Maureen Kearney, Mary Ellen Hannibal, Peter Alpert, Matt Kane, Jack Sites, Ed Braun, and Dan Graur.” That’s quite a list, but I made it to third! [I read the draft way back in 2022.]
“The Network of Life describes the drivers of horizontal evolution — inter–breeding and genetic recombination, the merger of species, horizontal gene transfer, and co–evolution. The network view of evolution that emerges supports a new symbiotic theory of health, which holds that the future health of humans, other species, and our shared environments depends on evolution and adaptations across life’s network.”As the author points out, the old “Germ Theory of Disease” focuses on human disease itself, whereas the new “Symbiotic Theory of Disease” focuses on human and environmental health. That is, human diseases stem from infection with certain organisms, whereas human health actually stems from the capacity to recover from disease and injury, and to adapt to change over time. So, in the latter the focus is on both short-term and longer-term relationships of other organisms in human and environmental health.
Now, the author mainly restricts himself to the complex network that exists between any given species and the disease–causing organisms that surround and inhabit it. However, I wish to look here at the medical status of humans and their interaction with their environment. Obviously, in this blog, the aspect of the environment under discussion will be the alcohol that the people transfer from their environment into their own bodies.
The basic idea is that there is no static optimum for the nature of the interaction (alcohol in this case) under discussion, because the relationships are evolving in both time and space. The World Health Organization’s declaration (January 2023) that there is “no safe level” of alcohol consumption (that does not affect health) makes little biological sense.
The book’s author notes:
“What do we mean by health? Human health is often taken to be the the mere absence of illness. That view may work on a short time scale. But over longer time frames, health and sickness are not mutually exclusive conditions. Reacting to a flu virus with a fever, aching joints, nausea, and swollen lymph glands, the classic signs of sickness, is a sign of good health, as manifest by a healthy immune system. Sickness and health co–exist, and a long life includes many periods of injury and sickness, followed by recoveries ... Because health and sickness vary over time, there is no narrow or statistically defined normal or abnormal state of these conditions. Environmental health is similarly dynamic. At all levels, health is more about resilience, adaptability to trauma, and persistence over time than it is about absence of sickness.”So, the idea that there could be a pre-specified amount of alcohol that humans can safely consume, medically, is naive. The amount that we could safely consume at one time in our life will not be the same as at another time. We adapt through time, based on what has already happened to us during our life — we meet our own medical needs over time by being resilient, and adjusting to change. There is no such thing as “normal” — it changes through time for each of us.
Furthermore, our body is a system of interactions among many components (organs, chemicals, micro–organisms). There is much evidence that the microorganisms in our body impact our behaviour. Their chemical compounds can and do stimulate our nervous system and brain, influencing our mood and actions. So, the host behaviour is not controlled by the host’s genes alone. There is no such thing as “normal” — it changes in space, as well.
Just as importantly, the amount of alcohol that we could safely consume thousands of years ago was not the same as now, nor will the amount we consume now be the same as a thousand years in the future. The human species has a long past (there is evidence of Neolithic wine, 8,000 years ago, at the site shown above**), and we will presumably have a long future (although we may change a lot during that time). There is the intriguing idea that our species has evolved while consuming alcohol, and interfering with that consumption might actually have negative effects on us.
For example, we know that reducing some of our previous environmental exposures has correlated with the increasing prevalence of allergies (Why our allergies are getting worse), and reducing exposure to some of our previous microbes may be correlated with the increasing prevalence of auto–immune diseases (The increasing prevalence of autoimmunity and autoimmune diseases). Thus, reducing our exposure to alcohol may actually have negative effects! [So might increasing it, of course.]
Publications
Morrison, D.A. (2011) Introduction to Phylogenetic Networks. RJR Productions, Sweden. vi+216 pp. ISBN 978-91-980099-0-3. [Formally reviewed here.]
Morrison, D.A. (2005) Networks in phylogenetic analysis: new tools for population biology. International Journal for Parasitology 35: 567-582.
Morrison, D.A. (2010) Using data-display networks for exploratory data analysis in phylogenetic studies. Molecular Biology and Evolution 27: 1044-1057.
Morrison, D.A. (2013) Phylogenetic networks are fundamentally different from other kinds of biological networks. In W.J. Zhang (ed.) Network Biology: Theories, Methods and Applications (Nova Science Publishers, New York) pp. 23-68.
Bapteste, E., van Iersel, L., Janke, A., Kelchner, S., Kelk, S., McInerney, J.O., Morrison, D.A., Nakhleh, L., Steel, M., Stougie, L. and Whitfield J. (2013) Networks: expanding evolutionary thinking. Trends in Genetics 29: 439-441.
* My networks blog went for 3,187 days (or 8 years 8 months 22 days). So far, this wine blog has gone for 3,036 days (8 years 3 months 22 days). So, I’m getting there. [Tom Wark suggests that the technology for wine blog publishing became “very accessible” around 2009 — his Fermentation blog actually started in November 2004, and moved on to a new platform in January 2022.]
** The Agricultural Revolution started 12,000 years ago, and the Wheel was developed 5,500 years ago.
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