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If you are only going to read one book on networks/ systems, let it be this. Whenever a physicist takes on the question of What is Life, like Erwin Schrödinger did in 1944, spectacular things come from it. Physicist Geoffrey West has carried on the Schrödinger tradition and given the world some serious food for thought.

This is probably going to be the longest review I have ever written because this is, without question, one of the most important books I have ever read and is an essential read for anyone who wants to better understand the changing face of evolutionary theory or better understand systems.

In Scale, Geoffrey West has written a paradigm shifting, seminal work in the area of evolution. In this book, West remains modest, so much so, a typical reader might not know how significant a contribution to the theory of evolution he has made. He does not detail the shortcomings or virtues of previous contributions to the theory. He merely relates to his reader what his decades of research have uncovered and how they relate to the theory of evolution. Since West did not give his reader an adequate understanding of how the past research of evolution has fallen short, and how his research, along with the work of other greats like Jermey England and Nick Lane, is changing the very fabric of the modern synthesis of evolution, I feel compelled to provide a short history of paradigms, so that West's works can be seen for the fundamental shift that it is. First though, I would like to thank the people in West's life who convinced him to write a popular book detailing his work. His previous book Scaling in Biology was decidedly written for scientists. Everything found in that book can be found in this book as well, only without the graphs and maths. West was again going to write a similar book, this time including his work on the metabolism of cities. When he told his ideas to Amazon's Jeff Bazos, historian Niall Ferguson, and other non scientists, they told him that his work was too important to keep in the ivory tower and that he must write in a way that conveys his brilliant ideas to curious minds of all educations levels. The result is this fantastic and mind-blowing book.

Many new and exciting additions to the conventional theory of evolution are being made to help researchers and the general public alike understand Darwinian evolution in more complete terms. Darwin got the ball rolling by helping citizens of the world understand that humans were not the result of God placing us here on Earth, already fully formed, but rather the result of heredity, as each population handed down modified traits to their offspring, over billions of years. Helping complete the picture of heredity, researchers like Neil Shubin and others helped map the gene switches that turned cells into fish, fish into tiktaalik, tiktaalik into treeshrews, and treeshrews into humans. This type of research really helped fill in our understanding of what role the environment and genes play in evolution. Unfortunately, until recently, progress for the theory has been significantly harmed by the very people who did the most to help convey the complex science of evolution to the general public. Richard Dawkins and other neo- Darwinists made it their job to speak for Darwin. They brought forth extremely incredible ideas that were exciting to the general public, who devoured them as they read articles and books, which all featured the star of evolution, the selfish gene. Trying to understand the selfish gene was worthwhile in the 1970s, when scientists still failed to understand the role that thermodynamics played in evolution. Prior to better understanding how thermodynamics affects the formation of living and non living systems, the emergence of life seemed like a wonderful accident. Indeed, Dawkins is still calling the emergence of life an "accident".

Unfortunately as time passed, Dawkins and his fellow old school Darwinists shamed, bullied, and discredited anyone who attempted to contribute new findings to the theory of evolution that would replace the notion of the selfish gene. Dawkins is famous for his vicious attacks on scientists such as E.O. Wilson, Eva Jablonka and other researchers working in the very exciting field of epigenetics. In response to anyone trying to include the role of epigenetic modification of genes in the process of heredity and evolution or anyone challenging kin selection by examining the role of cooperation in the process of evolution, Dawkins accused them of being uneducated and not understanding evolution. As the decades pressed on, it became clear that it was Dawkins, and not the researchers working on epigenetics and systems (networks), who did not fully understand the science of evolution. Dawkins learned new and exciting science that had occurred from 1859 (when Darwin's Origins was published); through the 40s and 50s when many advancements in understanding DNA, RNA, proteins, viruses, and molecule interactions took place; into the 70s when scientists had a fairly good understanding of the way genes work inside organisms throughout many, many generations. After the 70s, Dawkins (who did a lot to help the theory of evolution gain the respect it deserved) stopped paying attention to the newer science. He had written about the selfish gene and attacked anyone who threatened his selfish gene fame by showing it to be brilliant but outdated.

This brings us into the present, including Geoffrey West. More progressive researchers continued to expand their understanding of evolution to include more recent findings, such as how genes are epigenetically modified by various environmental factors and, more importantly, how thermodynamics, and not genes, truly drives the process of evolution. One of the most noteworthy researchers in this field is Jeremy England, an MIT professor who rocked the science world with his likely overhaul of Darwinian evolution. England calls Darwinian evolution a special case of a much larger and general phenomenon. In England's estimation, evolution itself is the process of dissipating energy. That is to say, living systems are really good at capturing and dissipating energy by converting it to heat. The emergence of life itself was merely a response to thermodynamics. Atoms gradually restructured themselves in order to dissipate increasingly more energy; that restructuring of atoms *is* life. To England and many of today's top researchers studying evolution, the emergence of life is *probable*, meaning that Dawkins' view of life being a random accident is outdated since it doesn't take into account the newer evidence on why and how atoms would assemble into lifeforms.

Nick Lane and his colleagues also shook things up in evolutionary research when they created models of the emergence of life at deep sea hydrothermal vents. Lane agrees with England that the emergence of life is actually expected in the given conditions and is not the random miraculous accident that Dawkins thinks it is. Like England, Lane and colleagues are focused on energy. Every living organism takes in nutrients packed with energy. Cells take in various nutrients (CO2, Na+, K+, Ca2+, etc) and expel waste products (H2O, CO2, etc) in order to remain active, repair, and reproduce. Plants take in nutrients (photons of light, carbon from the air, and water and nitrogen from soil) and expel waste products (H2O). Animals take in nutrients (oxygen, water, whole plants, other animals, grains, etc) and expel waste products (you know what you expel; no need to spell it out). All of these nutrients are packed with life giving energy- even that horrible donut you ate after telling yourself you wouldn't. Even the waste products themselves are wonderful energy packed nutrients. An animal's feces are a yummy energy filled treat to plants growing in soil. The oxygen that plants expel are poisonous to them, and if they could think, they might view oxygen waste just as we view feces as disgusting waste. But we *love* to breathe in their waste. Who doesn't love a fresh breath of oxygen rich air? No matter what the system (cell, plant, animal, or machine), it requires energy to live, reproduce, and evolve. Thus, anytime a theory of evolution cannot account for the energy necessary to evolve, that theory is unquestionably incomplete. Lane was able to provide the current best guess about from where life sprang, precisely because he came at the problem by asking what the energy source for creating new life might look like. It turned out that it is surprisingly easy to find the necessary energy at hydrothermal vents. Acidic conditions make it so there is a bubbling stream of rich nutrients that are pushed through the rocky vents. The pours in the rock are the shape and size of cells. It is believed that perhaps nutrients were taken under ground when they were submerged along with huge chunks of tectonic plates. Then the earth ripped apart the rock, freeing the nutrients. The nutrients, which can build the stuff of life, were then expelled through vents in the ocean floor where they went on to flow through the rocky membranes and make the molecules of life. But these first cells were stuck to the vents, because they were entirely dependent on the energy provided by vents. Over time, those cells developed channels that allowed them to take in nutrients that made enough energy to keep them alive when they floated away from the vents and out to sea to eventually evolve into single cells, then multicellular organisms, algae, plants, cartilage fish, boney fish (our ancestors), tiktaalik, horses, bats, monkeys, humans, insects, reptiles, dinosaurs, and more. No other theory can currently account for the energy needed to continue to remain active long enough to replicate. It might turn out that the RNA World hypothesis is correct (RNA came first and replicated itself, creating DNA, more RNA, and proteins) but it will first have to account for the energy needed for that first RNA to replicate.

Whatever the answer of how life began -- be it they hypothesis of Nick Lane et. al. that suggests it began at the hydrothermal vents, the RNA world hypothesis, or an altogether different hypothesis, it will *have to account for the energy needed*. The fact that Lane focused almost solely on that is what makes his guess stronger than any other guess currently on the table. England was able to gain fundamental new insights because he too focused almost entirely on energy -- what is the energy source that creates and feeds the form; what is the response of the forms to energy streaming, cycling through the system, or being transferred to heat as they leave the system; how do forms react to each other as they share the large energy sources among them (e.g. virtually all living forms on Earth have to share the energy sent by the sun in the form of photons, which are extremely energetic).

Geoffrey West too is obsessed with how energy enters a system, how it is extracted and turned into ATP as it cycles through that system, and how fast that energy is used up and what happens when it's gone. He is also interested in what makes up a system. Your cells in your body make up you. But what about each organ? What about your dependence on other animals to give you the energy you need so you can turn it into ATP to keep on living and producing offspring? What about the electricity and shelter of houses and buildings that humans depend on for their economies, healthcare, and daily living? West tries to understand the many networks that help cycle energy. Are there systems that act just like organisms? His answer is yes and no. Some systems that seem like they might be alive are merely constructed, while others (like cities and companies) exhibit the traits of energy consumption and energy evacuation that are remarkably similar to how animals metabolize energy. Whether or not West turns out to be right about cities and companies (something I am still thinking about), asking about evolution from this perspective will increase society's understanding a significant amount from the little we understood when Darwin first brought us his brilliant insights. This is because the answer *always* lies in energy consumption, conversion, and transfer. The answer always lies in thermodynamics because it is what drives everything. When someone can understand evolution through the lens of thermodynamics, then they will have the most complete and up to date understanding of the process that a human being can have. That understanding might still be limited, but it will be more complete than any theory or hypothesis that does not take thermodynamics/energy into account.

When looking at evolution in relation to energy production and consumption (and all that entails), researchers like England, Lane, and West make it easy to see that the emergence of life is far from a random accident. Instead, life is the result of all molecules following the laws of nature. Life arises when certain molecules, which are subjected to the same forces and laws that every molecule is exposed to, are exposed to the various conditions found on Earth. As has been pointed out in criticisms to Peter Ward's Rare Earth hypothesis, it's hard to say for sure if all of the conditions are necessary (a moon that holds the earth at an axis of 23 1/2 degrees, being at our exact proximity to the sun, having the exact # of planets in our solar system, being at our exact position in our galaxy, and so on) for the emergence of life, but it has become increasingly clear that life can and will emerge when subjected to conditions such as those on Earth because the molecules have *no choice* but to behave the way they do. England understood this well when, years ago, he stated that given everything we know about the fundamental laws of nature, the emergence and subsequent evolution of life "should be as unsurprising as rocks rolling down a hill." Believing in 2017 that life is a happy random accident, as Dawkins and his crew do, in the face of the abundance of evidence to the contrary, which has been filtering in for quite a while now, is to think exactly like the creationists the neo-Darwinists are fighting. At this point, it's absurd. I am so thankful for researchers like West who are ushering the theory of evolution into the 21st century.

With the summary over of why West's book is important to the theory of evolution, it's now onto the review of the actual book:

Most of the book deals with scaling in biological systems. As mentioned at the start of this review, West wrote a book Called Scaling in Biology, written for academics -- lots of graphs, detailed the maths, and was published in article form-- which blew my mind. I loved that book so much, I slept with it beside my bed for about a year, looking at it whenever I wanted to think more deeply about scaling. Basically, if West were hard pressed to narrow down what scaling in biology means (and he has been pressed to do so; look up his many wonderful talks and lectures on youtube) he would probably say something like this: Scaling means that all organisms are governed by the same physical laws, which makes them grow, live and die in remarkably similar ways. For example, every animal has about 1.5 billion heartbeats in a lifetime. Small mice have hearts that beat fast and use up their heartbeats very quickly, resulting in a very short lifespan. Large elephants, on the other hand, have hearts that beat slowly, making their 1.5 billion heartbeats occur over a much longer life span. But, why should this be so? Brilliantly, West has spent an entire career uncovering a few simple laws that put constraints on the evolution of any organism (or non organism for that matter). Because of the laws of physics, organisms must take in energy to remain active. They must unpack and harvest that energy and turn it into a waste product. The way every organism does this is the same. It doesn't matter if that organism is a huge blue whale, a tiny ant, or even a microscopic cell.

Understanding energy processing in organisms has allowed West to mostly (he is still working out some kinks here and there) understand everything in terms of networks and systems. Once he understood energy processing (metabolism), he could understand how an organism develops, what structures an organism can have, what role fractals play, what role power laws play, and more importantly for West, what other forms might metabolize just like living organisms. I have zero doubt that cities metabolize. The only thing that remains unclear to me is, to what extent does it actually scale with biological systems. I am not sure I like the measurement tools he used for companies. So again, I buy the argument that companies metabolize, that is process, energy. I am just not sure about the scaling aspect of it. Even with these concerns, the mere understanding of the common, truly universal, laws that apply to all systems (be it an organism or a city) is a significant contribution to society's understanding of how the laws of physics govern the world and larger universe.

When writing specifically about evolution, West challenges the notion of natural selection. In order to have selection, there must be variance. However, once organisms are understood in terms of systems, it is clear that there are many aspects of life that are invariant. West repeatedly describes this phenomenon throughout the book. Some of the most intersting parts of this book have to do with what West calls terminal units. For example, veins are scaled down versions or arteries, and capillaries are scaled down versions of veins. Thus, the capillaries, since they are fractals, are smaller versions of the arteries. The capillaries are the terminal units. (In cells the terminal units are things like respiratory units inside mitochondria). Most damage occurs at terminal units. This damage is aging. Terminal units also dictate how large an animal can get. (Check out West's captivating discussion on the Crow's radius. I loved that part so much). When West discusses aging, he does so in terms of entropy. It is the only way we should ever talking about aging. Brilliant!

What does the processing of energy, and the fractal nature of energy transfer, have to do with the fact that if you are cut on an artery, you die, but if you are cut on a capillary, you simply need a band-aid? West provides an entertaining answer.

In this book lies one of the best histories of the discovery of fractals. No other book that I can recall has given Richardson his due. Mandelbrot is always highlighted, as he should be, but Richardson rarely receives the recognition he has earned.

West spends quite a bit of time discussing aging. He believes Ray Kurzweil might be wrong about how long humans can live. West explains at length, but never assumes he is correct. He simply relates what he knows and tries to understand what constraints that might have for maximum human lifespan- even with the aid of technology. Personally, I think Kurzweil is far too optimistic, but I think West is discounting what future technology can do. Nothing can live forever. Our sun will eventually swallow the earth if something else doesn't crash into or eat it first. But humans might be able to live a bit longer than West suggest. I won't know the answer in my lifetime, but i enjoy the hypotheses. The take home message from West is that disease is not the leading cause of death. So, we have to take that into account.

A small criticism:

One thing that bothered me a great deal about this book was West's discussion of Zimbardo's prison and car studies. I think of West as a critical thinker. Zimbardo fiddled with his own studies! You cannot trust findings from researchers who do sketchy things. West accepts the results of Zimbardo's studies without critiquing them. It's a small complaint when I consider the rest of