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Life's Edge: The Search for What It Means to Be Alive
We all assume we know what life is, but the more scientists learn about the living world--from protocells to brains, from zygotes to pandemic viruses--the harder they find it is to locate life's edge.
Carl Zimmer investigates one of the biggest questions of all: What is life? The answer seems obvious until you try to seriously answer it. Is the apple sitting on your kitchen counter alive, or is only the apple tree it came from deserving of the word? If we can't answer that question here on earth, how will we know when and if we discover alien life on other worlds? The question hangs over some of society's most charged conflicts--whether a fertilized egg is a living person, for example, and when we ought to declare a person legally dead.Charting the obsession with Dr. Frankenstein's monster and how Coleridge came to believe the whole universe was alive, Zimmer leads us all the way into the labs and minds of researchers working on engineering life from the ground up.
Carl Zimmer investigates one of the biggest questions of all: What is life? The answer seems obvious until you try to seriously answer it. Is the apple sitting on your kitchen counter alive, or is only the apple tree it came from deserving of the word? If we can't answer that question here on earth, how will we know when and if we discover alien life on other worlds? The question hangs over some of society's most charged conflicts--whether a fertilized egg is a living person, for example, and when we ought to declare a person legally dead.Charting the obsession with Dr. Frankenstein's monster and how Coleridge came to believe the whole universe was alive, Zimmer leads us all the way into the labs and minds of researchers working on engineering life from the ground up.
368 pages, Hardcover
First published March 9, 2021
About the author
Carl Zimmer
52 books1,585 followersCarl Zimmer is a columnist for the New York Times and the author of 13 books about science. His latest book, She Has Her Mother's Laugh, will be published in May 2018. Zimmer is a frequent guest on Radiolab and has written hundreds of articles for magazines such as National Geographic, The Atlantic, and Wired. He is, to his knowledge, the only writer after whom a species of tapeworm has been named. Visit him at carlzimmer.com, on Facebook at facebook.com/carlzimmerauthor and on Twitter @carlzimmer.
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Displaying 1 - 30 of 278 reviews
June 13, 2021
Before I read this book, I didn't think it was a problem defining what was alive and what wasn't. Now, I'm no more sure than the scientists and philosophers. If something dies after a 100 days, then it was alive, right? That's red blood cells. Not many of us would say they were alive, had life.
The most fascinating thing so far is a pretty, yellow single-celled slime mould (that isn't really a mould) that can grow all across a forest floor, can learn and can pass on its knowledge, although no one knows how. This is Physarum.
Physarum is chemically-attracted to various nutritive elements, say sugar. It is always hunting whether tiny in a laboratory or huge across a forest floor. It puts out tentacles which eventually will sense the sugar and move towards it. Where the tentacles have been is left a slime trail. Physarum will not go again where it has left slime, so it has 'memory' of where it has been. It also can only go where the surface is damp.
Scientists constructed an acrylic maze with sugar at the ends of it and damped the base. Over 120 hours, the slime mould had not just found the sugar but had done so in the straightest possible way. So, in another experiment (not in the book) scientists
So, Carl Zimmer asks 'What is life?' and 'How did life begin?' The answer to the first is yet to be conclusively, scientifically defined, but we all know it when we see it. The answer to the second, only those who believe in creation stories know. The rest of us, that's an answer for the future. Maybe.
The most fascinating thing so far is a pretty, yellow single-celled slime mould (that isn't really a mould) that can grow all across a forest floor, can learn and can pass on its knowledge, although no one knows how. This is Physarum.
Physarum is chemically-attracted to various nutritive elements, say sugar. It is always hunting whether tiny in a laboratory or huge across a forest floor. It puts out tentacles which eventually will sense the sugar and move towards it. Where the tentacles have been is left a slime trail. Physarum will not go again where it has left slime, so it has 'memory' of where it has been. It also can only go where the surface is damp.
Scientists constructed an acrylic maze with sugar at the ends of it and damped the base. Over 120 hours, the slime mould had not just found the sugar but had done so in the straightest possible way. So, in another experiment (not in the book) scientists
"took 2,000 P. polycephalum specimens and trained them to cross a salt bridge to reach food. These were called “habituated” slime molds. Then, they took another 2,000 specimens and had them cross a bare bridge (no salt) to reach their food. They called these the “naive” slime molds. Then, they divided the specimens into habituated, naive, or mixed groups. The slime molds fused together when paired (a natural behavior). The researchers tested each fused group to see how quickly they would cross the salt bridge to reach food.So now, it is not just life that has become hard to define, but also intelligence, communication and learning.
What they found was quite remarkable - any group that had contained a habituated specimen crossed the salt bridge just as fast as a habituated specimen alone! They went a step further and separated the fused specimens and found that only naive specimens that had been fused to habituated specimens crossed the salt bridge. The researchers take this as proof of learning. Now the trick is to figure out how the slime molds pass their learning to other individuals." https://www.labroots.com/trending/mic...
So, Carl Zimmer asks 'What is life?' and 'How did life begin?' The answer to the first is yet to be conclusively, scientifically defined, but we all know it when we see it. The answer to the second, only those who believe in creation stories know. The rest of us, that's an answer for the future. Maybe.
April 5, 2022
…the question of what it means to be alive has flowed through four centuries of scientific history like an underground river… More than 150 years later, despite all that biologists have learned about living things, they still cannot agree on the definition of life.I have had the pleasure of driving up a mountain through mist and cloud, and of walking in London through pea soup fog. Where exactly did the clear air end and the more particulate air begin? It is not entirely…um…clear. Sure, there is a difference between standing, or driving in air that one cannot visually penetrate and looking through a wide outdoor expanse on a cloud-free, crystalline winter day. But it is not a barrier drawn with a straight edge. Thus it appears with the line between living and not-living. With the examples detailed in Life’s Edge, it is clearer than ever that there are more things under heaven and earth than had been dreamed of in our philosophies. There are those, certainly, who proclaim that this or that specific location is where the thing called life begins. Rules have been drawn up to plant markers, to draw lines. But like an outdoor crime-scene police-tape, the fog of what lies within and without wanders freely past those lines, with no regard for the designs or preferences of humans.
Carl Zimmer - image from The Psychology Podcast
New York Times science columnist and multiple-award-winning science-writer Carl Zimmer’s fourteenth book takes readers on an exploration to that amorphous borderland between the living and the non-living. It is a journey that raises a lot more questions than it answers. Zimmer employs a tried and true approach, each chapter moving on to the next lab, the next researcher, the next wild bit of research, and filling in with nice chunks of science history, as he circles around the question.
Alysson Muotri – image from The Stem Cell Podcast
Many of the things Zimmer reports on are fascinating. Some, however, will disturb your sleep. For an example of the latter, Alysson Muotri, at the Sanford Consortium for Regenerative Medicine, takes skin samples and reprograms them into neurons to study neurological diseases and possible treatments. They are grown into miniature organs called organoids, and are allowed to reproduce, up to a point. When he started growing these things, he assumed that they could never become conscious. “Now I’m not so sure, he confessed.” Zimmer tells, also, of a researcher, a very long time ago, who was notorious for experimenting on living animals.
Cerebral organoid - image from European Research Council
Clearly a significant concern for our culture is where “life” begins, and further, where “human life” begins. It all comes down to definitions. Is Thomas Aquinas’s notion of the “ensoulment” of human embryos the same as defining when life becomes human life? There have been other notions employed in the history of Christianity. Zimmer looks at how legal definitions of life, for purposes including supporting abortion laws, and concerning a widening spectrum of medical and legal issues, fail to hold up under scientific scrutiny.
”It’s Alive!” (or is it?) – from Frankenstein – image from Buzzfeed
The concern here is not just what is life, but how can we tell when something actually is alive? He looks at how humans perceive life and react to it. We have a sense of life being present or absent, an intuition that is not unique to our species. Ravens hold what can only be seen as funerals for dead flock members. Chimps engage in group laments for late members, as do many other creatures.
To be alive is to not be dead…Humanity did not come to this realization through logic and deduction. Our understanding of death is not like Darwin’s theory of evolution or Thompson’s discovery of the electron. It has its origins in ancient intuitions.Zimmer looks at metabolic rate. In the 17th century, there was a widespread fear of being afflicted with a death-like state that might leave its victims without detectable breath or heartbeat, thus generating a rampant terror of being buried alive. This concern inspired a well-known short story.
The boundaries which divide Life from Death are at best shadowy and vague. - Edgar Allan Poe, The Premature BurialZimmer reports on a woman who was pronounced dead, twice. (third time's the charm?) Where is the line between brain death and true, no backsies, total death? Can a person meet the criteria for brain death one day, and later not meet it?
From The Night of the Living Dead - image from Wikipedia
But what constitutes life? How about adding some ingredients to agar, leaving it alone for a few hours and then finding a thriving slime mold, one with remarkable survival skills. What about spores, some of which can survive in space? Are spores alive? Or only potentially alive, or an ingredient in a recipe for making life?
Scientists have been arguing over whether viruses are alive for about a century, ever since the pathogens came to light. Writing last month in the journal Frontiers in Microbiology, two microbiologists (Hugh Harris and Colin Hill) at University College Cork took stock of the debate. They could see no end to it. “The scientific community will never fully agree on the living nature of viruses,” they declared. - from Zimmer’s Secret Life piece in the NY Times
“I vunder vut it vood be like to be really dead” – image from The Indy Channel
Whether you prefer your undead to be of the vampiric, zombie, or reanimated sort, or are more inclined to unicellular spore candidates, or maybe pre-conscious organoids, there are plenty of candidates for entities on the fringes of life.
In addition to providing readers with a better handle on the attempt to delineate the line between life and not-life, there are plenty of interesting questions raised and fun facts to be gleaned. We learn, for example, that Erwin Schr��dinger was set up by the government at Trinity College. (But he may have simultaneously both been there and not, depending on whether any students saw him give a lecture.) We also learn that when Vitamin C was discovered, the discoverer wanted to name it “Godnose.” And how about meteorites as a possible source of Terran life? Or maybe they contributed one or more of the ingredients necessary for the recipe? I particularly enjoy when science writers imbue their work with a sense of humor. That is mostly lacking here, which is disappointing. But there is plenty of material to keep your brain cells flashing on and off.
Who decides on a definition of life? In an ideal world, science should lead on matters that are subject to physical investigation and repeatable experimentation. And yet…
It may be enough for you to align with Supreme Court Justice Potter Stewart who, when it came time to issue a ruling pertaining to pornography, said that he knows it when he sees it. We as a species tend to think that we know life when we see it. But it would be a good thing to recognize that all extant definitions of life are squishy, relying on philosophy or religion for their support. So I would appreciate it if no one would use their definition to tell me or anyone who does not share their perspective what they can or cannot do. Because when it comes to folks twisting science to political ends, I know it when I see it.
Life’s Edge may not provide a definitive guide to the line between living and nonliving. Such a line does not really exist in biology. But it does point out where the arguments lie about where those lines might be drawn, or, at least, where they might be investigated. It raises the larger question, though, of whether that line can, at least from a scientific perspective, be drawn at all.
Life is what the scientific establishment (probably after some healthy disagreement) will accept as life.
Review first posted – March 19, 2021
Publication dates
----------March 9, 2021 - hardcover
----------March 8, 2022 - trade paperback
I received an e-book ARE if Life’s Edge from Dutton in exchange for an honest review, and some of those interesting things that have been growing, unasked, in my basement.
This review has been cross-posted on my site, Coot’s Reviews. Stop by and say Hi!
=============================EXTRA STUFF
Links to the author’s personal, FB, Instagram, Tumblr, PInterest, and Twitter pages
I heartily recommend you check out Siddhartha Mukherjee's amazing NY Times review What Does It Mean to Be a Living Thing?
Items of Interest from the author
-----What is Life - audio – A series of live conversations between writer Carl Zimmer and eight leading thinkers on the question of what it means to be alive.
-----Slate – excerpt - What on Earth are These Things? - on organoids
-----NY Times - The Secret Life of a Coronavirus - is it alive?
Songs/Music
-----From Sondheim’s Company - Being Alive
-----Aerosmith - Livin’ On the Edge
-----Opening of Saturday Night Fever – The Bee Gees Stayin’ Alive
-----Madonna - Borderline
-----GaGa - Edge of Glory
-----Shruti Haasan - Edge
-----Monty Python’s The Meaning of Life - Every Sperm is Sacred
April 23, 2021
. (A tardigrade, also known as a waterbear or moss piglet. Photo by Frank Fox on Wikimedia Commons)
It's hard to go wrong with a book that talks about tardigrades, one of my favourite species. These little critters are fascinating. They are eight-legged microanimals that are almost indestructible and can even survive in outer space.
Tardigrades are a cryptobiotic species, meaning they can dehydrate themselves and be in a state of limbo between life and death for years. They display none of the signs of life while in this state and yet if you pour water on them, even after decades of being "dead", within minutes they become "a moving, feeding, reproducing animal".
So what are tardigrades when they're in a cryptobiotic state? Are they alive or are they dead? Is there a third state of being in between life and death that creatures such as tardigrades, nematodes, and rotifers enter into?
And what exactly is life anyway?
Author Carl Zimmer explores this question in alluring detail. He looks at many life forms, from tardigrades to trees; from Amazon mollies to bats; and viruses, bacteria, humans, pythons, and more.
He discusses the metabolic and reproductive processes that we generally use to attribute life, and examines the thin line between life and death. Biologists do not even agree on what exactly life is. If the experts can't tell us, is it possible to know?
I found most of this book gripping and hard-to-put-downable. I loved going along with Mr. Zimmer as he visited biologists and botanists and experts on various forms of life.
There is also a lot of discussion on scientists and others through the last few centuries, what they studied and learned and what they thought of life. After a while, some of this became tedious and I preferred learning what scientists today think and know.
Aside from that, this is a riveting book. Mr. Zimmer is an engaging and informative writer. Anyone with even a loose interest in biology will likely enjoy this book. And if you are as intrigued by tardigrades and slime molds as I am, you will especially enjoy it!
February 20, 2022
Zimmer takes us through several centuries of discoveries in biology focused on the search for the origin of and the definition of life. The book is a selective biology history mixed with some philosophy and modern research. Zimmer’s vignettes keep us entertained with a series of interesting characters and events. The style is breezy, definitely not intimidating, mixing in a lot of human interest with the science. It is a readable if somewhat meandering introduction to what life is and how it came about.
Zimmer explores the boundary between life and death. He visits a lab where brain organoids are grown in a chemical solution. The brain cells were developed from human skin cells chemically reprogrammed to become neurons. The neurons in the small globular mass of cells comprising the organoid communicate with each other and form brain waves just like a normal brain. If one taps a beat on a surface near the organoid, the waves from the organoid will learn to respond in kind. The cells are functioning as would those in the cerebral cortex. They are alive as cells, but are they experiencing any form of greater consciousness. What does it mean to be alive as a human being? The issue is an endless controversy that rages on the issue of abortion and death. Is death when the heart stops or when brain waves can no longer be detected?
Zimmer looks at the different ways animals suspend activity to survive. Bats and bears eat hearty then hibernate in the winter. Maple trees shut down their leaf factories in the fall, but store the precious chlorophyll in the branches to use for a fast start in the spring. Pythons go long stretches between meals. But when they eat, they eat big. Eating a rat that was a quarter of its body weight, a python named Haydee grew her heart 40% bigger, her kidneys, intestines and liver doubled in weight, her metabolism ramped up ten times, the internal projections in her intestines grew six times longer, then after digestion her organs and metabolism returned to their normal size and pace. Nematodes, rotifers and tardigrades can dry out and be resurrected when hydrated again. Tardigrades have been put in cold storage for thirty years and with a little warmth and water returned to normal. Perhaps most fascinating of Zimmer’s menagerie are slime molds which can dry out, break into fragments and be carried by the wind to land on a wet spot where each piece then is resurrected as a fully functional slime mold. Zimmer’s discussion reveals many more amazing attributes of slime molds.
Zimmer profiles scientists who focused on what makes something alive. He begins in the 18th century in Holland with Abraham Trembley who discovered Hydra in a nearby stream. He was amazed that he could cut it in half and each half would regenerate the other half. What made this possible? If the soul was the essence of life, did it split in Half? Next was Albrecht von Haller whose gruesome experiments on animals showed that when its heart stopped beating it died. The ability of muscle fibers to contract signified life, apparently independent of the soul. In the 19th century Friedreich Wohler showed that urea he made artificially in a lab was the same as that produced by the human body. At that time people did not believe the human body was made from the same elements as inorganic materials. By the late 1800s scientist knew living things produced enzymes. In the 1890s Eduard Buchner showed that yeast used enzymes to break down sugar and make alcohol. He was awarded the noble prize in 1907. In the early twentieth century scientist began to see that a cell wasn’t just a blob of protoplasm but a miniature factory with numerous components moving about. Noble prize winner Albert Szent-Gyorgyi who discovered vitamin C in 1928 went on to show that the molecule ATP produced in the cells from carbohydrates provided the power for muscles and other reactions in cells. But how did cells reproduce. Scientists began to closing on chromosomes as the suspect. Nobel Prize winner Erwin Schrödinger turned to cellular biology writing What is Life in 1944. Inspired by Schrödinger’s book, nine years later Francis Crick and James Watson with the critical help of Rosalind Franklin figured out the structure of DNA, the code book of life.
In the 1920s and 30s, Soviet biochemist Alexander Oparin wrote books that opened eyes to the fact that the earth on which life started was far different than the one we inhabit today. The atmosphere had almost no oxygen and lots of carbon dioxide. Volcanoes and seismic activity proliferated spewing and mixing chemicals producing hydrocarbons. Somehow life emerged from this orbiting laboratory. In the ongoing search to define life Oparin noted ”Life is not characterized by any special properties, but by a definite, specific combination of these properties.” In 1953 Stanly Miller took some gases believed to have been in the early earth’s atmosphere (methane, ammonia, hydrogen and water vapor) enclosed them a glass container with some water, a condenser to make rain, and an electrode simulate lightening. Running overnight it produced amino acids, the building blocks of life and other carbon molecules. His experiment made big news and scientists began conducting many more similar experiments.
Zimmer does a long piece on David Deemer who began in the 1970s experimenting with lipids which form cell membranes. His goal was to show how chemical reactions, particularly those that take place in a volcanic or superheated undersea vent environment, could organize lipids that would capture chemicals needed to make RNA. Many scientists believe RNA based life preceded DNA based life. His experiments were promising, but still required lots of interventions. Zimmer goes on to describe NASA’s search for life outside the earth and ends musing on the seeming impossibility of defining exactly what life is.
For readers interested in digging a little deeper a couple of books come to mind: Adam Rutherford’s Creation: How Science Is Reinventing Life Itself about the creation of synthetic life and Nick Lane’s The Vital Question: Energy, Evolution, and the Origins of Complex Life about the creation of natural life. Also relevant is Robert Hazen’s The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet.
Zimmer explores the boundary between life and death. He visits a lab where brain organoids are grown in a chemical solution. The brain cells were developed from human skin cells chemically reprogrammed to become neurons. The neurons in the small globular mass of cells comprising the organoid communicate with each other and form brain waves just like a normal brain. If one taps a beat on a surface near the organoid, the waves from the organoid will learn to respond in kind. The cells are functioning as would those in the cerebral cortex. They are alive as cells, but are they experiencing any form of greater consciousness. What does it mean to be alive as a human being? The issue is an endless controversy that rages on the issue of abortion and death. Is death when the heart stops or when brain waves can no longer be detected?
Zimmer looks at the different ways animals suspend activity to survive. Bats and bears eat hearty then hibernate in the winter. Maple trees shut down their leaf factories in the fall, but store the precious chlorophyll in the branches to use for a fast start in the spring. Pythons go long stretches between meals. But when they eat, they eat big. Eating a rat that was a quarter of its body weight, a python named Haydee grew her heart 40% bigger, her kidneys, intestines and liver doubled in weight, her metabolism ramped up ten times, the internal projections in her intestines grew six times longer, then after digestion her organs and metabolism returned to their normal size and pace. Nematodes, rotifers and tardigrades can dry out and be resurrected when hydrated again. Tardigrades have been put in cold storage for thirty years and with a little warmth and water returned to normal. Perhaps most fascinating of Zimmer’s menagerie are slime molds which can dry out, break into fragments and be carried by the wind to land on a wet spot where each piece then is resurrected as a fully functional slime mold. Zimmer’s discussion reveals many more amazing attributes of slime molds.
Zimmer profiles scientists who focused on what makes something alive. He begins in the 18th century in Holland with Abraham Trembley who discovered Hydra in a nearby stream. He was amazed that he could cut it in half and each half would regenerate the other half. What made this possible? If the soul was the essence of life, did it split in Half? Next was Albrecht von Haller whose gruesome experiments on animals showed that when its heart stopped beating it died. The ability of muscle fibers to contract signified life, apparently independent of the soul. In the 19th century Friedreich Wohler showed that urea he made artificially in a lab was the same as that produced by the human body. At that time people did not believe the human body was made from the same elements as inorganic materials. By the late 1800s scientist knew living things produced enzymes. In the 1890s Eduard Buchner showed that yeast used enzymes to break down sugar and make alcohol. He was awarded the noble prize in 1907. In the early twentieth century scientist began to see that a cell wasn’t just a blob of protoplasm but a miniature factory with numerous components moving about. Noble prize winner Albert Szent-Gyorgyi who discovered vitamin C in 1928 went on to show that the molecule ATP produced in the cells from carbohydrates provided the power for muscles and other reactions in cells. But how did cells reproduce. Scientists began to closing on chromosomes as the suspect. Nobel Prize winner Erwin Schrödinger turned to cellular biology writing What is Life in 1944. Inspired by Schrödinger’s book, nine years later Francis Crick and James Watson with the critical help of Rosalind Franklin figured out the structure of DNA, the code book of life.
In the 1920s and 30s, Soviet biochemist Alexander Oparin wrote books that opened eyes to the fact that the earth on which life started was far different than the one we inhabit today. The atmosphere had almost no oxygen and lots of carbon dioxide. Volcanoes and seismic activity proliferated spewing and mixing chemicals producing hydrocarbons. Somehow life emerged from this orbiting laboratory. In the ongoing search to define life Oparin noted ”Life is not characterized by any special properties, but by a definite, specific combination of these properties.” In 1953 Stanly Miller took some gases believed to have been in the early earth’s atmosphere (methane, ammonia, hydrogen and water vapor) enclosed them a glass container with some water, a condenser to make rain, and an electrode simulate lightening. Running overnight it produced amino acids, the building blocks of life and other carbon molecules. His experiment made big news and scientists began conducting many more similar experiments.
Zimmer does a long piece on David Deemer who began in the 1970s experimenting with lipids which form cell membranes. His goal was to show how chemical reactions, particularly those that take place in a volcanic or superheated undersea vent environment, could organize lipids that would capture chemicals needed to make RNA. Many scientists believe RNA based life preceded DNA based life. His experiments were promising, but still required lots of interventions. Zimmer goes on to describe NASA’s search for life outside the earth and ends musing on the seeming impossibility of defining exactly what life is.
For readers interested in digging a little deeper a couple of books come to mind: Adam Rutherford’s Creation: How Science Is Reinventing Life Itself about the creation of synthetic life and Nick Lane’s The Vital Question: Energy, Evolution, and the Origins of Complex Life about the creation of natural life. Also relevant is Robert Hazen’s The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet.
July 12, 2021
"We cannot make artificial life because we cannot agree on what life is. We cannot find life on Mars because we cannot agree what life represents". --Radu Popa
Scientists still cannot agree on a definition of life. That is because life comes in so many forms and structures; there is no single definition that can encompass them all. That is the central theme of Carl Zimmer's book.
Zimmer's writing is excellent! He is a science columnist for the New York Times. He wrote a number of books. I really enjoyed his book She Has Her Mother's Laugh: The Powers, Perversions, and Potential of Heredity. I expect to read additional books he has written.
The early portion of his book discusses what is a human. When did humans first evolve? Zimmer writes a number of interesting anecdotes about primate behaviors and their reactions to death. One hundred-thousand years ago, homo sapiens began carrying out funerals. This demonstrates that people understood that diseases and injuries cause death.
Zimmer writes about flowers that were buried by Ice Age squirrels 30,000 years ago in Siberia. Scientists have nurtured them back into healthy plants. He writes about hibernating bats. He writes about Covid-19. Famous Hungarian biochemist Szent-Györgyi said that self-reproduction is not a requirement for life. As a humorous aside, he gave as an example that a single rabbit cannot reproduce.
The tail end of the book discusses the origin of life. Some scientists believe that the most important components or requirements for life are shell membranes called "liposomes". They act as containers for life's molecules. Scientists have made liposomes by adding water to meteorites. Other scientists find that visiting the Kamchatka Peninsula is a great place to study early-Earth-like conditions. The peninsula is packed with active volcanoes, crater lakes, hot springs and ponds.
This is just a small sample of all the topics discussed in this book. The author does not try to be humorous. Instead, he captivates the reader with an amazing assortment of stories about scientists who have tried to define the edge between the non-living and life. Highly recommended!
January 29, 2022
'Life's Edge' by Carl Zimmer fascinated me! The subtitle threw me off - 'The Search for What it Means to be Alive' - and so I thought it's one of those so-called books of science like The Planets which struck me as a fatuous rhapsodic ode of literary excess rather than, you know, a science book.
*ahem*
I put the book aside for a few weeks after picking it up from the library, thinking I'd get to it after I finished some other book club selections. After the library renewed it - twice - I sighed, and figured I could look at it anyway.
I loved it! The subtitle referred to the difficulty biologists are having in recognizing what is alive and what is not alive when studying certain...well, things/objects/creatures. Coronoviruses may not be alive, for instance.
o _ O
The chapter on slime molds kept me reading into the night. Scientists can't define what kind of life it is, only that there are several kinds of slime molds. It is a thing in its own category. It's a single-celled -something- which can spread across a forest. It moves towards food. It throbs, it grows and retracts tentacles, it can do mazes. It can look like a web, or milk or dog's vomit. It looks like a dead black crust or it becomes flakes in a drought or sunlight, apparently very dead. But it comes back to life if the environment improves months later.
Another critter which comes back to life after apparently dying is a tardigrade. They can lose all of their water, no longer capable of any of the chemical reactions necessary for life, only to revive months later when given water. This is called cryptobiosis. Flies, fungi, bacteria are all resurrectable. Moss found after glaciers retreated sprouted after being frozen for at least six hundred years. Flower bits grew into narrow-leafed campion after the bits were discovered in an ice-age burrow built by squirrels 30,000 years ago.
Scientists can't help themselves but explore to try to see if they can discover why objects live. They do so even when they get embarrassed by discoveries of life forms which turn out to not be alive later, like Bathybius, a sticky ocean floor mud - was it protoplasm? Maybe the First Cause of Life?Scientists believed Life maybe formed in the Ocean, so sea oozes and jellies got people excited. Until it was learned byproducts of some chemical actions appear organic.
The book describes experiments from the seventeenth century, when microscopes that could see "animalcules' in water were made, to our present time. Why do animalcules move? What makes human bodies move? In the 1700's, physicians believed it was a substance inside nerves they called animal spirits. But movement isn't always caused by nerves. Hearts will continue to pump after being removed from the body. Is it Will? The 'irritability' of body parts, internal and external, were stimulated by a touch of a knife or chemical in tests. Gruesome tests, gentle reader. Some people may want to skim this chapter. But any claims of the body having an animating force under the power of that body certainly irritated religious forces of the era, gentle reader, as you can imagine.
As the decades passed and tech improved, scientists discovered cells, then the stuff inside of cells, then the parts of the stuff inside of cells. Omg, red blood cells! Are they alive? Maybe, but they don't have any DNA. They can't make proteins or divide into new cells - part of most definitions of Life - yet they are vital to our bodies in carrying oxygen.
One scientist, Cleber Trujillo, can make brain organoids from skin cells. They look like pale globes, consisting of thousands of human neurons, each developed from a single progenitor cell. They build themselves, repair themselves, fire electric signals in waves - just like brains inside of our heads. They are cortex organoids and can survive for years. From skin cells.
Um. Brain organoids. But not a human being, right? Right? This is a little uncomfortable, yes? Alive? Or not?
How to define Life? The arguments continue. The author describes the philosophical battles discussed by various scientists' points of view who have been arguing the point for centuries. Apparently the progress made in explorations of cells and nerves and membranes, of DNA and lipids and proteins, of sexual reproduction and of repair mechanisms and of cell parts, of viruses which are apparently working under the principle of Schrodinger's dead but not physics, of critters and plants which survive millennia as dead things but are revived by water, by critters found surviving on poisonous metals pumped out of deep underwater volcanic mounds under enormous pressure and heat.- all have definitely confused the boundaries of Life already confused by slime molds and beating hearts outside the body - and inside too - brain-death victims kept alive by machines and chemicals and feeding tubes.
Note: there is a discussion about pregnancy, abortion, birth defects, which I found to be very interesting. Basically, the judges sometimes decide they can't resolve the question of when life begins because, even though various judges have decided anyway against abortion rights or supported them - there is no simple answer to when life begins when it involves being close-up and personal to the boundaries of Life. Fetuses naturally abort a lot more than is commonly known. Does that make mom a criminal? Actually, moms who have naturally aborted HAVE gone to prison, gentle reader. DNA can be examined to see defective genes in a ball of undifferentiated human cells.The heartbeat issue resolves nothing because heart cells beat all by themselves with a body or not, even when there is only one heart cell. Heart cells can be grown in a Petrie dish. Are they alive? Are viruses alive? Are red blood cells alive? Are brain-dead people alive? The courts have weighed in resolving most of the current issues, but the arguments continue between those who know most of the real science through reproducible research results and those ordinary people who argue their points without knowing a single science fact except that from non-scientific religious books.
*ahem*
The book has extensive Notes and Bibliography sections. There also is an Index.
This is a link to a terrific review of this book a thousand times better than mine:
https://www.goodreads.com/review/show...
By Will Byrnes
*ahem*
I put the book aside for a few weeks after picking it up from the library, thinking I'd get to it after I finished some other book club selections. After the library renewed it - twice - I sighed, and figured I could look at it anyway.
I loved it! The subtitle referred to the difficulty biologists are having in recognizing what is alive and what is not alive when studying certain...well, things/objects/creatures. Coronoviruses may not be alive, for instance.
o _ O
The chapter on slime molds kept me reading into the night. Scientists can't define what kind of life it is, only that there are several kinds of slime molds. It is a thing in its own category. It's a single-celled -something- which can spread across a forest. It moves towards food. It throbs, it grows and retracts tentacles, it can do mazes. It can look like a web, or milk or dog's vomit. It looks like a dead black crust or it becomes flakes in a drought or sunlight, apparently very dead. But it comes back to life if the environment improves months later.
Another critter which comes back to life after apparently dying is a tardigrade. They can lose all of their water, no longer capable of any of the chemical reactions necessary for life, only to revive months later when given water. This is called cryptobiosis. Flies, fungi, bacteria are all resurrectable. Moss found after glaciers retreated sprouted after being frozen for at least six hundred years. Flower bits grew into narrow-leafed campion after the bits were discovered in an ice-age burrow built by squirrels 30,000 years ago.
Scientists can't help themselves but explore to try to see if they can discover why objects live. They do so even when they get embarrassed by discoveries of life forms which turn out to not be alive later, like Bathybius, a sticky ocean floor mud - was it protoplasm? Maybe the First Cause of Life?Scientists believed Life maybe formed in the Ocean, so sea oozes and jellies got people excited. Until it was learned byproducts of some chemical actions appear organic.
The book describes experiments from the seventeenth century, when microscopes that could see "animalcules' in water were made, to our present time. Why do animalcules move? What makes human bodies move? In the 1700's, physicians believed it was a substance inside nerves they called animal spirits. But movement isn't always caused by nerves. Hearts will continue to pump after being removed from the body. Is it Will? The 'irritability' of body parts, internal and external, were stimulated by a touch of a knife or chemical in tests. Gruesome tests, gentle reader. Some people may want to skim this chapter. But any claims of the body having an animating force under the power of that body certainly irritated religious forces of the era, gentle reader, as you can imagine.
As the decades passed and tech improved, scientists discovered cells, then the stuff inside of cells, then the parts of the stuff inside of cells. Omg, red blood cells! Are they alive? Maybe, but they don't have any DNA. They can't make proteins or divide into new cells - part of most definitions of Life - yet they are vital to our bodies in carrying oxygen.
One scientist, Cleber Trujillo, can make brain organoids from skin cells. They look like pale globes, consisting of thousands of human neurons, each developed from a single progenitor cell. They build themselves, repair themselves, fire electric signals in waves - just like brains inside of our heads. They are cortex organoids and can survive for years. From skin cells.
Um. Brain organoids. But not a human being, right? Right? This is a little uncomfortable, yes? Alive? Or not?
How to define Life? The arguments continue. The author describes the philosophical battles discussed by various scientists' points of view who have been arguing the point for centuries. Apparently the progress made in explorations of cells and nerves and membranes, of DNA and lipids and proteins, of sexual reproduction and of repair mechanisms and of cell parts, of viruses which are apparently working under the principle of Schrodinger's dead but not physics, of critters and plants which survive millennia as dead things but are revived by water, by critters found surviving on poisonous metals pumped out of deep underwater volcanic mounds under enormous pressure and heat.- all have definitely confused the boundaries of Life already confused by slime molds and beating hearts outside the body - and inside too - brain-death victims kept alive by machines and chemicals and feeding tubes.
Note: there is a discussion about pregnancy, abortion, birth defects, which I found to be very interesting. Basically, the judges sometimes decide they can't resolve the question of when life begins because, even though various judges have decided anyway against abortion rights or supported them - there is no simple answer to when life begins when it involves being close-up and personal to the boundaries of Life. Fetuses naturally abort a lot more than is commonly known. Does that make mom a criminal? Actually, moms who have naturally aborted HAVE gone to prison, gentle reader. DNA can be examined to see defective genes in a ball of undifferentiated human cells.The heartbeat issue resolves nothing because heart cells beat all by themselves with a body or not, even when there is only one heart cell. Heart cells can be grown in a Petrie dish. Are they alive? Are viruses alive? Are red blood cells alive? Are brain-dead people alive? The courts have weighed in resolving most of the current issues, but the arguments continue between those who know most of the real science through reproducible research results and those ordinary people who argue their points without knowing a single science fact except that from non-scientific religious books.
*ahem*
The book has extensive Notes and Bibliography sections. There also is an Index.
This is a link to a terrific review of this book a thousand times better than mine:
https://www.goodreads.com/review/show...
By Will Byrnes
March 21, 2024
“Yaşamın Kıyısında” popüler bilim kitabı. Canlı olmanın ne anlama geldiğini sorgulayan araştıran bir kitap. Dört ana bölüm içinde 17 ayrı konuyu hikaye anlatırcasına yazmış Carl Zimmer. Covid dahil güncel konulara gelene kadar 3-4 yüzyıl içinde dolaşmış.
Temel amacı “yaşam-hayat nedir” sorusuna yanıt aramak, ancak buna ne bilimsel, ne felsefi tam ve doyurucu bir cevap olmadığını saptadığından, yaşamın kıyısında büyülü bir gezi yapıyor. Çok ilginç ve çarpıcı bilgilerle dolu.
Bilime, özellikle biyokimya, biyoloji ve genetik dallarına ilgi duyuyorsanız mutlaka okuyun.
Temel amacı “yaşam-hayat nedir” sorusuna yanıt aramak, ancak buna ne bilimsel, ne felsefi tam ve doyurucu bir cevap olmadığını saptadığından, yaşamın kıyısında büyülü bir gezi yapıyor. Çok ilginç ve çarpıcı bilgilerle dolu.
Bilime, özellikle biyokimya, biyoloji ve genetik dallarına ilgi duyuyorsanız mutlaka okuyun.
September 29, 2021
I was especially interested in reading this with the Science & Inquiry group since it's a question that's been on my mind since a dendrologist in a recent book said the bulk of tree wood was 'dead'. Others don't think so, but apparently we don't have a good definition for "life" or "death". I hoped that this book would shed some light on the subject. It didn't, but it was still an interesting trip through the history of our search for an answer & it was quite up to date.
The book started out slow for me since a lot of it was a rehash of what I'd read recently, but it got more intriguing as he explored some of the newer science relating to it. Here on Earth we have plenty of examples of things that are in the borderland such as viruses & red blood cells. When we start thinking about alien biology, the ground gets even shakier. Usually I'm not much of a fan of philosophy, but I found some solace in the idea that we might not know enough to be able to define "life" yet much in the same way as the alchemists failed to define water.
Well narrated & pleasant enough to read. Not great, but more satisfying than I would have expected.
The book started out slow for me since a lot of it was a rehash of what I'd read recently, but it got more intriguing as he explored some of the newer science relating to it. Here on Earth we have plenty of examples of things that are in the borderland such as viruses & red blood cells. When we start thinking about alien biology, the ground gets even shakier. Usually I'm not much of a fan of philosophy, but I found some solace in the idea that we might not know enough to be able to define "life" yet much in the same way as the alchemists failed to define water.
Well narrated & pleasant enough to read. Not great, but more satisfying than I would have expected.
February 28, 2021
Ok, I totally see why Carl Zimmer is such a popular science writer now. This was great, really interesting and well told stories around various iterations of life and why it’s so complicated to define what that actually means. It was mostly accessible for a non sciencey type like me too, but I did make the mistake of reading it too often before bed and then would get lost in some scientific definitions and the like. Still! Incredible learning experience and exciting stories.
January 16, 2024
Carl Zimmer okumayı çok sevdiğim, çok öğretici popüler bilim kitapları yazıyor. Daha önce okuduğum Evrim, evrim üzerine yazılmış en güncel ve derli toplu kitaptı. Bu kitabında da yine o saygı duyulası tavrı var.
Yaşamın Kıyısında isminden tahmin edileceği gibi yaşamı sorgulayan bir kitap. Yaşamın nerede başlayıp nerede bittiği, canlılığın ne anlama geldiğini bulmaya çalışıyor. Kitabı yazma motivasyonu ilk kısımda belli oluyor. Amerika başta olmak üzere pek çok ülkede kürtaj tartışmaları var. Sağ kesimin ateşli bir şekilde savunduğu kürtaj karşıtlığının en çok kullanılan argümanı da bunun bir cinayet olduğu. Zimmer fetüsün canlılığını birçok bilim insanının çalışmasından yola çıkarak tartışıyor. Kürtaj karşıtlarına göre döllenmeden itibaren canlılık söz konusu. Zimmer döllenen yumurtanın rahme inmesinden çok daha sonra yaşam denen şeye kavuştuğunu söylüyor. Döllenen yumurtanın bazen kadın fark etmeden bile kanama ile atıldığını söylüyor. Eğer buna ölüm denirse dünya çapındaki ölüm istatistiklerinin tamamen değişeceğini ve en büyük ölüm sebebinin döllenmiş yumurta ölümü olacağını anlatıyor. Zimmer kürtaj karşıtlarına bilimsel olarak karşı çıkıyor. Okurken sosyal alana direkt bir cevap vermiş olmasını takdir ettim.
Bu vurucu bölümden sonra canlılığın ne anlama geldiğini bilim tarihinde arıyor. Her bölümü büyük ilgiyle okudum. 18. yüzyıl natüralistlerinden modern deneylere büyük bir yelpazesi var. Çağdaş bir çalışma olan organoidler, elektrikle hareket eden kurbağa bacağı ve virüslerin yaşamı gibi bildiğimizi sandığımız konuların keşif sürecini anlatıyor. Kitap çok verimli çok keyifli.
Kitap birçok saygın ödül almış. 2021 Wilson Edebi Bilim Yazımı Ödülü alması ilgimi çekti başlamadan önce. Kitap ödülün hakkını veriyor. Zimmer harika bir üslupla yazmış. Bilim kitabını hevesle, heyecanla okumak nadir yaşanan bir durum. Ele aldığı konuya verdiği örneklerin konuları da çok geniş. Alanı olmayan okurların da ilgiyle takip edeceği bir okuma sunuyor.
Yaşamın Kıyısında isminden tahmin edileceği gibi yaşamı sorgulayan bir kitap. Yaşamın nerede başlayıp nerede bittiği, canlılığın ne anlama geldiğini bulmaya çalışıyor. Kitabı yazma motivasyonu ilk kısımda belli oluyor. Amerika başta olmak üzere pek çok ülkede kürtaj tartışmaları var. Sağ kesimin ateşli bir şekilde savunduğu kürtaj karşıtlığının en çok kullanılan argümanı da bunun bir cinayet olduğu. Zimmer fetüsün canlılığını birçok bilim insanının çalışmasından yola çıkarak tartışıyor. Kürtaj karşıtlarına göre döllenmeden itibaren canlılık söz konusu. Zimmer döllenen yumurtanın rahme inmesinden çok daha sonra yaşam denen şeye kavuştuğunu söylüyor. Döllenen yumurtanın bazen kadın fark etmeden bile kanama ile atıldığını söylüyor. Eğer buna ölüm denirse dünya çapındaki ölüm istatistiklerinin tamamen değişeceğini ve en büyük ölüm sebebinin döllenmiş yumurta ölümü olacağını anlatıyor. Zimmer kürtaj karşıtlarına bilimsel olarak karşı çıkıyor. Okurken sosyal alana direkt bir cevap vermiş olmasını takdir ettim.
Bu vurucu bölümden sonra canlılığın ne anlama geldiğini bilim tarihinde arıyor. Her bölümü büyük ilgiyle okudum. 18. yüzyıl natüralistlerinden modern deneylere büyük bir yelpazesi var. Çağdaş bir çalışma olan organoidler, elektrikle hareket eden kurbağa bacağı ve virüslerin yaşamı gibi bildiğimizi sandığımız konuların keşif sürecini anlatıyor. Kitap çok verimli çok keyifli.
Kitap birçok saygın ödül almış. 2021 Wilson Edebi Bilim Yazımı Ödülü alması ilgimi çekti başlamadan önce. Kitap ödülün hakkını veriyor. Zimmer harika bir üslupla yazmış. Bilim kitabını hevesle, heyecanla okumak nadir yaşanan bir durum. Ele aldığı konuya verdiği örneklerin konuları da çok geniş. Alanı olmayan okurların da ilgiyle takip edeceği bir okuma sunuyor.
June 5, 2021
I loved the idea of this book. As a biology teacher, this is a topic that is most fascinating.
This book had a lot of idea not previously mentioned in other popular science books. For instance, he explores the history of wrongful ideas of what life means. I had no idea that there was a massive scientific flub where Burke claimed to find life that wasn't really there. He also does a philosophical exploration into what life actually is and how we have still failed to get a real definition in place.
I also really liked the pieces on odd life like the tardigrades and viruses. What a bizarre type of life do dessicate and come back into being. I personally do think the restriction of life to viruses is a bit odd since parasites also cannot breed without a host. I get it, but I think that something that evolves (without humanity's guiding hand) can be considered living. I guess I am too generous!
The only reason I didn't give it 4 stars (5 stars are rarer for me), is that I suppose I disliked the organization of the book. I couldn't really follow the logic of it. Starting with history before, then unusual life forms, then back to Miller's experiment with organic molecules, THEN to life's definition.... kind of jarring. A few of the chapter (such as the formation of organic molecules) felt a bit on the dry side. I still think this is a good read for biology enthusiasts. I just would have edited it differently. Some images might have helped, too.
This book had a lot of idea not previously mentioned in other popular science books. For instance, he explores the history of wrongful ideas of what life means. I had no idea that there was a massive scientific flub where Burke claimed to find life that wasn't really there. He also does a philosophical exploration into what life actually is and how we have still failed to get a real definition in place.
I also really liked the pieces on odd life like the tardigrades and viruses. What a bizarre type of life do dessicate and come back into being. I personally do think the restriction of life to viruses is a bit odd since parasites also cannot breed without a host. I get it, but I think that something that evolves (without humanity's guiding hand) can be considered living. I guess I am too generous!
The only reason I didn't give it 4 stars (5 stars are rarer for me), is that I suppose I disliked the organization of the book. I couldn't really follow the logic of it. Starting with history before, then unusual life forms, then back to Miller's experiment with organic molecules, THEN to life's definition.... kind of jarring. A few of the chapter (such as the formation of organic molecules) felt a bit on the dry side. I still think this is a good read for biology enthusiasts. I just would have edited it differently. Some images might have helped, too.
August 24, 2021
Very well written and interesting. I especially liked the sections on 'the RNA world' that speculate on how life came to be on earth, and experiments to simulate early conditions and see whether cells could develop. A happy side effect of these experiments was the development of the very fast DNA sequencers without which the human genome project would not have finished in centuries (it completed a few years ago). About the RNA world: I'm a bit disappointed that nobody, afaik, has yet created an RNA-based 'artificial' life form in the lab, since most of the ingredients should be well known by now.
Personally, I think viruses or other life forms that depend on certain environmental characteristics should not be called 'not alive' because of that. This because then one might as well call humans 'not alive', since they depend on an environment providing e.g. oxygen to breathe.
See also this and this excellent reviews which convinced me to read this book.
Personally, I think viruses or other life forms that depend on certain environmental characteristics should not be called 'not alive' because of that. This because then one might as well call humans 'not alive', since they depend on an environment providing e.g. oxygen to breathe.
See also this and this excellent reviews which convinced me to read this book.
June 19, 2021
In Life's Edge, Carl Zimmer sets out to explore the line that separates life and non-life, what means to be alive, and the impossible task of giving life a definition.
Many forms of lives or partial lives are examined. Apparently some scientists do not consider viruses as lives, even though when they infect animals, plants and bacterias, they are certainly alive. Under extreme conditions, animals can retreat into "half life", such as bats in hibernation and tardigrades in outer space. They are not dead since they can be revived, but when they exist without metabolism, they do not behave as alive.
Slime, a single-celled organism, is so fascinating that I am going to read more on it. They have no brains, but can solve puzzles, and leave “memories” in the outside world.
The author also examines the definition of life and death in human societies. He peels open the anti-abortionists’ argument that human life begins at conception by stating that fertilized eggs during the early stage of development are alive in the same way as cells in your body are alive, but they are not life yet, and such a view of when human life begins is scientifically untrue and logically flawed.
The history of how brain death became the standard definition of death is fascinating and a little scary.
Of course, the author has something to say about Darwin's theory of evolution and the discovery of DNA, and he focuses on how they affect our understanding of what life is. He then moves on to how life begins on the earth - volcano pond or deep ocean vent? Scientists have created organic molecules from scratch in labs by mimicking volcano ponds that could have existed 3 billion years ago.
The best part of the book is the definition of life, or our continuous effort to define life. Life is what people think they know but hardly able to give an exhaustive definition.
The NASA definition of life is “a self-sustaining chemical system capable of Darwinian evolution”, which was distilled by Trifonov in 2011 as "Life = Self-Reproduction with Variations". But the argument is far from settled. The last chapter, Four Blue Droplets, the author explains the assembly theory of life. He says, "a theory of life may end up looking a lot like the theory of superconductivity - it may explain life as a particular configuration of matter that gets a special quality from the physics of the universe. "
Many forms of lives or partial lives are examined. Apparently some scientists do not consider viruses as lives, even though when they infect animals, plants and bacterias, they are certainly alive. Under extreme conditions, animals can retreat into "half life", such as bats in hibernation and tardigrades in outer space. They are not dead since they can be revived, but when they exist without metabolism, they do not behave as alive.
Slime, a single-celled organism, is so fascinating that I am going to read more on it. They have no brains, but can solve puzzles, and leave “memories” in the outside world.
The author also examines the definition of life and death in human societies. He peels open the anti-abortionists’ argument that human life begins at conception by stating that fertilized eggs during the early stage of development are alive in the same way as cells in your body are alive, but they are not life yet, and such a view of when human life begins is scientifically untrue and logically flawed.
The history of how brain death became the standard definition of death is fascinating and a little scary.
Of course, the author has something to say about Darwin's theory of evolution and the discovery of DNA, and he focuses on how they affect our understanding of what life is. He then moves on to how life begins on the earth - volcano pond or deep ocean vent? Scientists have created organic molecules from scratch in labs by mimicking volcano ponds that could have existed 3 billion years ago.
The best part of the book is the definition of life, or our continuous effort to define life. Life is what people think they know but hardly able to give an exhaustive definition.
The NASA definition of life is “a self-sustaining chemical system capable of Darwinian evolution”, which was distilled by Trifonov in 2011 as "Life = Self-Reproduction with Variations". But the argument is far from settled. The last chapter, Four Blue Droplets, the author explains the assembly theory of life. He says, "a theory of life may end up looking a lot like the theory of superconductivity - it may explain life as a particular configuration of matter that gets a special quality from the physics of the universe. "
May 22, 2022
Science is real! So he doesn't really answer the question but the science is far ranging and provides much food for thought. Biology is a weakness for me so I appreciate any of it I can get.
February 12, 2021
Summary: An exploration of how scientists attempt (and have failed) to define what life is and the quest to understand how life arose.
Philosophers talk about the meaning of life. Carl Zimmer offers us a glimpse into the world of scientists who are trying to define what is life. What is the definition of life and when can something be defined as alive? What about particles like viruses and prions that appear dead until they interact with other living matter? And how did life originate here, and has it in other places in our solar system and beyond?
Zimmer takes us on an exploratory tour of this question that begins in the Cavendish Laboratory in 1904 with John Butler Burke who believed he had created the missing link between inorganic and organic life when he released grains of radium into a sterile broth and discovered under a microscope that shapes were there and were dividing. He called them radiobes and he believed that the radium provided the “vital flux” to turn the constituent elements into blobs of protoplasm. Eventually, he was disproven by other scientists after enjoying fleeting fame.
Zimmer takes us through the history of research on life from van Leeuwenhoek’s discoveries of microscopic life, to the growth of neural networks in laboratories. We go with him to pools near the mouths of volcanoes where some think organic life developed to discussions with researchers studying vents in the ocean. We enter caves to learn of the homeostatic relationship between hibernating bats and parasites who live off them and can kill them if they draw too much energy from the bat. We read of research demonstrating the lifelessness of soil samples on Mars and a meteorite from Mars that may evidence signs of life. I learned that red blood cells have no chromosomes and cannot divide and multiply like other cells.
Zimmer recounts the efforts of scientists to re-create the conditions under which they think life arose, whether it is in forming a strand of RNA or figuring out how to form a lipid membrane of the sort that surround every cell. Some scientists believe that the constituents of life have to come together fast, within 10,000 hours, because of the entropic forces that would destroy the constituents. That leads some to believe that they will achieve this in the next ten years.
In the end, he comes back to the question of the definition of life, cataloging the many scientists have proposed. He introduces us to Carol Cleland, a philosopher of scientist who thinks the whole enterprise is flawed and that what is needed is not a definition of life but a theory of life that helps us understand what life is.
As one reads Zimmer’s account, one realizes what is so fascinating in this quest to understand life and how it is possible. Zimmer introduces us to so many forms of life and the wonder of a planet teaming with life from microbes to every other form of life including ourselves. Some religious believers dismiss this whole quest to understand life and its origins with a wave of the hand saying, “God did it.” I’m not so quick to dismiss these quests. I realize some see nothing beyond the physical reality. Others, and I include myself here, would recognize in every scientific discovery the wonders and wisdom of God. If someone replicates the physical processes by which life arose, I will be delighted rather than distraught. My faith doesn’t rest on the gaps in our knowledge remaining gaps.
Zimmer gives us a glimpse at the reality of science. He shows us both the amazing things we are learning about the world, and the questions that remain, some on which multiple generations of scientists will work. He shows us the mistakes, and the ways that continued research and the rigorous peer review processes of science correct those mistakes. He shows us the big questions and what we still don’t know. This is great science writing!
________________________________
Disclosure of Material Connection: I received a complimentary review copy of this book from the publisher via Edelweiss. The opinions I have expressed are my own.
Philosophers talk about the meaning of life. Carl Zimmer offers us a glimpse into the world of scientists who are trying to define what is life. What is the definition of life and when can something be defined as alive? What about particles like viruses and prions that appear dead until they interact with other living matter? And how did life originate here, and has it in other places in our solar system and beyond?
Zimmer takes us on an exploratory tour of this question that begins in the Cavendish Laboratory in 1904 with John Butler Burke who believed he had created the missing link between inorganic and organic life when he released grains of radium into a sterile broth and discovered under a microscope that shapes were there and were dividing. He called them radiobes and he believed that the radium provided the “vital flux” to turn the constituent elements into blobs of protoplasm. Eventually, he was disproven by other scientists after enjoying fleeting fame.
Zimmer takes us through the history of research on life from van Leeuwenhoek’s discoveries of microscopic life, to the growth of neural networks in laboratories. We go with him to pools near the mouths of volcanoes where some think organic life developed to discussions with researchers studying vents in the ocean. We enter caves to learn of the homeostatic relationship between hibernating bats and parasites who live off them and can kill them if they draw too much energy from the bat. We read of research demonstrating the lifelessness of soil samples on Mars and a meteorite from Mars that may evidence signs of life. I learned that red blood cells have no chromosomes and cannot divide and multiply like other cells.
Zimmer recounts the efforts of scientists to re-create the conditions under which they think life arose, whether it is in forming a strand of RNA or figuring out how to form a lipid membrane of the sort that surround every cell. Some scientists believe that the constituents of life have to come together fast, within 10,000 hours, because of the entropic forces that would destroy the constituents. That leads some to believe that they will achieve this in the next ten years.
In the end, he comes back to the question of the definition of life, cataloging the many scientists have proposed. He introduces us to Carol Cleland, a philosopher of scientist who thinks the whole enterprise is flawed and that what is needed is not a definition of life but a theory of life that helps us understand what life is.
As one reads Zimmer’s account, one realizes what is so fascinating in this quest to understand life and how it is possible. Zimmer introduces us to so many forms of life and the wonder of a planet teaming with life from microbes to every other form of life including ourselves. Some religious believers dismiss this whole quest to understand life and its origins with a wave of the hand saying, “God did it.” I’m not so quick to dismiss these quests. I realize some see nothing beyond the physical reality. Others, and I include myself here, would recognize in every scientific discovery the wonders and wisdom of God. If someone replicates the physical processes by which life arose, I will be delighted rather than distraught. My faith doesn’t rest on the gaps in our knowledge remaining gaps.
Zimmer gives us a glimpse at the reality of science. He shows us both the amazing things we are learning about the world, and the questions that remain, some on which multiple generations of scientists will work. He shows us the mistakes, and the ways that continued research and the rigorous peer review processes of science correct those mistakes. He shows us the big questions and what we still don’t know. This is great science writing!
________________________________
Disclosure of Material Connection: I received a complimentary review copy of this book from the publisher via Edelweiss. The opinions I have expressed are my own.
June 24, 2022
What does it mean to be alive? What constitutes life? In Life's Edge Zimmerman provides different examples that may shed some light on these profound questions. Take the hardy tardigrade for example. These microscopic creatures will enter a near-death hibernation called cryptobiosis, and can stay in this state for very long periods. Add a drop of water and they will spring to life. If a human died of dehydration, you can bet that dumping a bucket of water onto the cadaver won't help reinvigorate it.
Take water from a nearby pond and examine it under a microscope. Looking into the viewer, you may be surprised to see an explosion of minute organisms swimming around. These critters must live such fleeting lives. If the pond dries up, they are wiped from existence. I remember Neil DeGrasse Tyson in Cosmos discussing the evanescent life of microorganisms in a single dew drop. The sun rises, life evaporates into thin air.
I will be forever in gratitude to science, for keeping that brittle flower of child-like wonder and curiosity healthy and well watered. I often will find an ant scurrying along a sidewalk, and I will study it, watching it move to and fro. The realization hits me like a brick every time -- it is alive. The birds flying overhead are alive. The earthworms slithering out of the wet soil are alive. In a way, Earth is alive, with its tectonic plates crashing, volcanoes erupting, hurricanes blowing furiously.
We are surrounded by life. It's important to stop and look once in a while. It is food for the soul.
Take water from a nearby pond and examine it under a microscope. Looking into the viewer, you may be surprised to see an explosion of minute organisms swimming around. These critters must live such fleeting lives. If the pond dries up, they are wiped from existence. I remember Neil DeGrasse Tyson in Cosmos discussing the evanescent life of microorganisms in a single dew drop. The sun rises, life evaporates into thin air.
I will be forever in gratitude to science, for keeping that brittle flower of child-like wonder and curiosity healthy and well watered. I often will find an ant scurrying along a sidewalk, and I will study it, watching it move to and fro. The realization hits me like a brick every time -- it is alive. The birds flying overhead are alive. The earthworms slithering out of the wet soil are alive. In a way, Earth is alive, with its tectonic plates crashing, volcanoes erupting, hurricanes blowing furiously.
We are surrounded by life. It's important to stop and look once in a while. It is food for the soul.
April 24, 2021
As the subtitle says, this book is about how 'life' as we know it is defined, how it began, and how we can make the distinction between what is alive and what is not.
While the answers at first seemed obvious, Zimmer draws on historical figures and anecdotes about life and current scientific research to learn from marginal cases. Examples such as slime molds, tardigrades, and viruses raise as many questions as answers. The benefits of such a broad approach in science writing are useful - at least for me, the lay reader - in forming connections, however limited, across disciplines and focuses of study.
While the answers at first seemed obvious, Zimmer draws on historical figures and anecdotes about life and current scientific research to learn from marginal cases. Examples such as slime molds, tardigrades, and viruses raise as many questions as answers. The benefits of such a broad approach in science writing are useful - at least for me, the lay reader - in forming connections, however limited, across disciplines and focuses of study.
August 17, 2023
What an interesting book. A mix of biology and philosophy
September 26, 2021
[25 Sept 2021]
I am a devoted fan of Carl Zimmer's writing, but this book was ultimately disappointing. Though that may in fact have been intended. His answer to the question, of course, is "We don't know". We don't know what "life" is or what it means to be alive or how life originated.
But Zimmer does his usual masterful job of exploring all the various attempts at answers, as well as much of the history of the search, as well as those areas of modern life where the question is particularly pertinent. He starts out with the abortion debate, then gets into end of life issues, then spends a lot of time describing the work of scientists attempting to determine how life began. During that section he gets a little in the weeds and I found myself occasionally bored and a little impatient. Then he covers the lengthy arguments scientist have had about how to define life. He ends with one scientist who says we shouldn't even try to define life and another who has a promising approach to the question.
I'm still frustrated that we don't have any clear answers, but this book does an excellent job of explaining why we don't have answers. Because it's complicated.
I am a devoted fan of Carl Zimmer's writing, but this book was ultimately disappointing. Though that may in fact have been intended. His answer to the question, of course, is "We don't know". We don't know what "life" is or what it means to be alive or how life originated.
But Zimmer does his usual masterful job of exploring all the various attempts at answers, as well as much of the history of the search, as well as those areas of modern life where the question is particularly pertinent. He starts out with the abortion debate, then gets into end of life issues, then spends a lot of time describing the work of scientists attempting to determine how life began. During that section he gets a little in the weeds and I found myself occasionally bored and a little impatient. Then he covers the lengthy arguments scientist have had about how to define life. He ends with one scientist who says we shouldn't even try to define life and another who has a promising approach to the question.
I'm still frustrated that we don't have any clear answers, but this book does an excellent job of explaining why we don't have answers. Because it's complicated.
May 28, 2021
I had a joyful ride with this one,the author tried to compile the history of science and the struggle of answering these two questions "what is life" and "where did life come from".
The journey that he took us on this book, from the medical/ethical dilemma of brain death,mysteries lives of bats,pythons,tardigrades and viruses to what is the most correct definition of life,it's both enlightening, intriguing and confusing on some parts.
I do believe the intention of this book was not to try to provide answers on these two questions but to bring to light,the debate and that still exist on the scientific community concern these two subjects,also to not ignore the progress that has been made throughout the years trying to answers these questions,on that Zimmer did a superb job.
Carl Zimmer is a must read for anybody who likes science writing and history of science but this one is a required read for anybody who loves life science..
The journey that he took us on this book, from the medical/ethical dilemma of brain death,mysteries lives of bats,pythons,tardigrades and viruses to what is the most correct definition of life,it's both enlightening, intriguing and confusing on some parts.
I do believe the intention of this book was not to try to provide answers on these two questions but to bring to light,the debate and that still exist on the scientific community concern these two subjects,also to not ignore the progress that has been made throughout the years trying to answers these questions,on that Zimmer did a superb job.
Carl Zimmer is a must read for anybody who likes science writing and history of science but this one is a required read for anybody who loves life science..
March 27, 2022
“Dare to think!”"What is life?" is a question with many different answers. To come at a new definition of life, the author draws on both science and history in this book. It begins with stories from ancient times about life's basic concepts and concludes with the most recent scientific findings.
― Immanuel Kant, What is Enlightenment?
The book, in my opinion, could use more mythological tales about the meaning of life.
Page 55
As Van Leeuwenhoek put his little animals into a deathlike state, people across Europe were worrying that they might slip into one of their own. They read pamphlets full of terrifying tales of seizures that left their victims without breath or heartbeat. Mistaken for dead, they were lowered into graves, waking up in their coffins when it was too late to be saved.
The fear of this Gothic terror gained strength throughout the eighteenth century and only grew more terrifying in the nineteenth. Edgar Allan Poe mined the nightmare for his story “The Premature Burial,” which he published in 1844. “The boundaries which divide Life from Death are at best shadowy and vague,” Poe wrote. “Who shall say where the one ends, and where the other begins?”
Families made frantic by these stories bought coffins equipped with a string and a bell, so that their not-quite-departed loved ones could sound the alarm. In the 1800s, many German cities built ornate “waiting mortuaries” where the apparently dead could be housed until they began to rot.
May 1, 2021
What does it mean to be alive?
That's the question, embedded in this book's subtitle, that sold me on reading this. But I'm not sure that Carl Zimmer — whose day job is as a science writer for The New York Times — really ever answers the questions. What "Life's Edge" does instead is to turn the question back on the reader.
"So you think life begins at conception, anti-abortion advocates? Well, then what about Physarum — a single-celled yellow slime that grows remarkably fast and shows the ability to remember where it's been? What about viruses? What about skin cells? What about ..."
The fact is, most of the examples Zimmer cites — one in each chapter, at least — I can't even remember. Several scientific names are batted around, and Zimmer makes an effort to boil a number of complicated concepts down, all in an effort to say that, yes, life is hard to define. Anyone who draws a line showing where life begins likely doesn't know what they're talking about — so why be so absolutist about it?
I agree, but I was hoping for something a little bit more ... absolute, I suppose. Or maybe a deeper dive into the ways life has been depicted in culture throughout time. There's a bit of that, but Zimmer largely sticks to the science.
That isn't a surprise, and I have only myself to blame for wanting more of a philosophical — rather than a purely scientific — look at existence.
That's the question, embedded in this book's subtitle, that sold me on reading this. But I'm not sure that Carl Zimmer — whose day job is as a science writer for The New York Times — really ever answers the questions. What "Life's Edge" does instead is to turn the question back on the reader.
"So you think life begins at conception, anti-abortion advocates? Well, then what about Physarum — a single-celled yellow slime that grows remarkably fast and shows the ability to remember where it's been? What about viruses? What about skin cells? What about ..."
The fact is, most of the examples Zimmer cites — one in each chapter, at least — I can't even remember. Several scientific names are batted around, and Zimmer makes an effort to boil a number of complicated concepts down, all in an effort to say that, yes, life is hard to define. Anyone who draws a line showing where life begins likely doesn't know what they're talking about — so why be so absolutist about it?
I agree, but I was hoping for something a little bit more ... absolute, I suppose. Or maybe a deeper dive into the ways life has been depicted in culture throughout time. There's a bit of that, but Zimmer largely sticks to the science.
That isn't a surprise, and I have only myself to blame for wanting more of a philosophical — rather than a purely scientific — look at existence.
March 20, 2021
Fascinating! I tend to study life as it is currently rather than spend time pondering what life is exactly and how it came to be, but I enjoyed going a little way down that rabbit hole. Zimmer is an engaging writer. (I also enjoyed She Has Her Mother’s Laugh.) Its funny...halfway through the book I found myself thinking “I figured this book would be more about abiogenesis than the definition of life and the extremes that help/make it more difficult to define it. About four sentences later, Zimmer transitioned into a discussion of abiogenesis. Really cool stuff!!
March 17, 2021
There are scattered sections with interesting unfamiliar information, but for the most part if the reader has had a general biology class it's mostly review. Darwin, Watson, Crick, Vitamin C, all covered here and not in a novel or interesting way. And who really cares about coming up with a definition of life? It's pointless imho. It's another meaningless attempt to classify something that can't be classified. See "Why Fish Don't Exist".
April 21, 2024
Zimmer presents some fascinating stories and vignettes, but ultimately fails to tie them together. Lost interest after the first two sections.
May 4, 2021
What is life? A question I think most are fascinated by, as it seems like such a simple, straightforward question but when it comes to answering it, the response comes out a bit garbled. Even from the most eminent and experienced scientists, the definition for ‘what is life’ is a difficult one.
This book was beyond absolutely fantastic at arming the reader with all sorts of research, history, examples, encounters with scientists and researchers and details of all things life-y. It makes you realise what an intricate and complex question it is, but provides you with the material to apply it to the original question at hand - or helping you to realise why it might not be such a great idea after all.
It’s written spectacularly (a similar trait across all of the authors books I’ve found) and is perfect for the scientist and non scientist alike. I actually learnt so much from this book (even having touched upon this topic before and tackled a definition during my studies) and there was so much more to learn. From the false starts to trying to define how life originates so current and ongoing research which was so interesting to read.
This is a book I’d happily have on my shelf and want to revisit again in the future. It was a really enjoyable and informative read, entertaining from the authors writing style and one that the pages whittled down into nothing in no time.
This book definitely got me thinking, in terms of at what point does life begin? The potentials of how, it’s origins and our journeys of scientific and philosophical discovery about life. The field of astrobiology is also an incredibly interesting one, and I also really enjoyed hearing from the different scientists in different fields attempting to tackle the age old question about life.
This book really got my brain firing and I really really enjoyed reading it!
I was lucky enough to read this with thanks to the author and publishers via NetGalley in return for my honest thoughts and review.
This book was beyond absolutely fantastic at arming the reader with all sorts of research, history, examples, encounters with scientists and researchers and details of all things life-y. It makes you realise what an intricate and complex question it is, but provides you with the material to apply it to the original question at hand - or helping you to realise why it might not be such a great idea after all.
It’s written spectacularly (a similar trait across all of the authors books I’ve found) and is perfect for the scientist and non scientist alike. I actually learnt so much from this book (even having touched upon this topic before and tackled a definition during my studies) and there was so much more to learn. From the false starts to trying to define how life originates so current and ongoing research which was so interesting to read.
This is a book I’d happily have on my shelf and want to revisit again in the future. It was a really enjoyable and informative read, entertaining from the authors writing style and one that the pages whittled down into nothing in no time.
This book definitely got me thinking, in terms of at what point does life begin? The potentials of how, it’s origins and our journeys of scientific and philosophical discovery about life. The field of astrobiology is also an incredibly interesting one, and I also really enjoyed hearing from the different scientists in different fields attempting to tackle the age old question about life.
This book really got my brain firing and I really really enjoyed reading it!
I was lucky enough to read this with thanks to the author and publishers via NetGalley in return for my honest thoughts and review.
July 29, 2021
I was so excited for this book. It's hard to go wrong with such fascinating content as LIFE and all of its edge cases, right? Unfortunately, wrong. We got off on the wrong foot when he chose to dive into abortion in like the second chapter. After a "well, actually" moment where he points out that the zygote has an extra set of chromosomes at the moment of conception (so that couldn't be where life begins), he then punts completely and changes the topic. My second main complaint is the organization, or rather lack thereof. We jumped around chronologically, topically, etc. We spent dozens of pages learning about how one dude started to study snakes, and then he mentioned the Amazonian mollies in about half a page. This book badly needed an outline and some editing. Finally, it bothered me how he introduced so many scientists and then referred to them, by name, chapters later as if we were supposed to remember! I felt so lost most of the time while reading the book, and it wasn't because the science was beyond me.
Two very specific gripes that I had highlighted:
"Once the scientists figured out how Zika viruses wreak their havoc, they were able to discover drugs that could block them." - Seriously, could we get a slightly more facile understanding of how scientific research works?
"[before hibernation, a] northern long-eared bat may put on an extra two grams of fat. Imagine surviving a five-month famine on half a teaspoon of butter." - That's exactly the wrong analogy to make and the wrong message to send! These bats are tiny and the incredible thing is that they're putting on so much weight! The actual equivalent would be more like us gaining and losing 50+ pounds every year, not TWO GRAMS.
Two very specific gripes that I had highlighted:
"Once the scientists figured out how Zika viruses wreak their havoc, they were able to discover drugs that could block them." - Seriously, could we get a slightly more facile understanding of how scientific research works?
"[before hibernation, a] northern long-eared bat may put on an extra two grams of fat. Imagine surviving a five-month famine on half a teaspoon of butter." - That's exactly the wrong analogy to make and the wrong message to send! These bats are tiny and the incredible thing is that they're putting on so much weight! The actual equivalent would be more like us gaining and losing 50+ pounds every year, not TWO GRAMS.
August 6, 2021
Zimmer says that this book is about what life is, but I found that sort of question was less interesting to me than the stuff he describes about organisms that periodically become *less* alive. Pythons that deactivate their GI systems between meals and bats going through torpor were great to hear about, but I particularly liked his argument that viruses should be considered life *when and only when* they are infecting a cell.
Despite the principle-ness of “life”— we are not discussing a problem, such as natural selection, or a solution, such as niches — Zimmer dives pretty happily into the land of “more or less”. I find questions like “is something more alive or less alive?” to be more defensible (and disputable) than “what is life?”, and he teeters around such arguments throughout the book.
Despite the principle-ness of “life”— we are not discussing a problem, such as natural selection, or a solution, such as niches — Zimmer dives pretty happily into the land of “more or less”. I find questions like “is something more alive or less alive?” to be more defensible (and disputable) than “what is life?”, and he teeters around such arguments throughout the book.
December 23, 2021
There’s always a few of these examining nature books each year.
A few catch on and are reviewed and promoted widely - this is one such book.
I’ve read many of these so Zimmer’s entry is not very new.
Here’s my take on life and his last chapters seem to track the same ground.
Life finds the semiotics of the universe.
Life differs from non life in that it stores information.
This stored info allows Life to push back against entropy - the force that takes down all non life eventually.
RNA and DNA are stored information. Math, language, and writing are stored info.
Math comes closest, and is most effective in deriving whatever the underlying semiotics of the universe are.
A better math could mean a better handle on manipulating the universe.
A few catch on and are reviewed and promoted widely - this is one such book.
I’ve read many of these so Zimmer’s entry is not very new.
Here’s my take on life and his last chapters seem to track the same ground.
Life finds the semiotics of the universe.
Life differs from non life in that it stores information.
This stored info allows Life to push back against entropy - the force that takes down all non life eventually.
RNA and DNA are stored information. Math, language, and writing are stored info.
Math comes closest, and is most effective in deriving whatever the underlying semiotics of the universe are.
A better math could mean a better handle on manipulating the universe.
May 31, 2022
The book explores what is it that defines something as living, and in the process exposes that the question is not that simple. While there are many surprising examples of systems that would challenge our normal perception of the living world, overall the book has little new to offer in terms of deeper insights.
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