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What Does a Martian Look Like? : The Science of Extraterrestrial Life
"A fascinating and useful handbook to both the science and science fiction of extraterrestrial life. Cohen and Stewart are amusing, opinionated, and expert guides. I found it a terrific and informative piece of work-nothing else like it!"
-Greg Bear
"I loved it."
-Larry Niven
"Ever wonder about what aliens could be like? The world authority is Jack Cohen, a professional biologist who has thought long and hard about the vast realm of possibilities. This is an engaging, swiftly moving study of alien biology, a subject with bounds and constraints these authors plumb with verve and intelligence."
-Gregory Benford
"A celebration of life off Earth. A hearteningly optimistic book, giving a much-needed antidote to the pessimism of astrobiologists who maintain that we are alone in the universe-a stance based on a very narrow view of what could constitute life. A triumph of speculative nonfiction."
-Dougal Dixon, author of
After Man: A Zoology of the Future
-Greg Bear
"I loved it."
-Larry Niven
"Ever wonder about what aliens could be like? The world authority is Jack Cohen, a professional biologist who has thought long and hard about the vast realm of possibilities. This is an engaging, swiftly moving study of alien biology, a subject with bounds and constraints these authors plumb with verve and intelligence."
-Gregory Benford
"A celebration of life off Earth. A hearteningly optimistic book, giving a much-needed antidote to the pessimism of astrobiologists who maintain that we are alone in the universe-a stance based on a very narrow view of what could constitute life. A triumph of speculative nonfiction."
-Dougal Dixon, author of
After Man: A Zoology of the Future
369 pages, Paperback
First published September 5, 2002
13 people are currently reading
285 people want to read
About the author
Jack Cohen
52 books16 followersJack Cohen was a reproductive biologist and science fiction consultant and author.
Librarian Note: There is more than one author in the GoodReads database with this name.
Librarian Note: There is more than one author in the GoodReads database with this name.
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Displaying 1 - 14 of 14 reviews
October 28, 2007
I hated this book. Perhaps its because I was expecting all science, some discussion on what might evolve in different enviroments. Now I know that we don't know, and have no good guess. What this book turned out to be is criticism of science fiction. I might have been fine with that if they seemed impartial, and talked about plausibility of each fictional world, but it seemed to me that if they were consulted the science fiction was fabulous, if they were not it was bad. Another thing they went on and on about was how the aliens would not be comprehensible to us, not feel things like us or emotions like us... we would not be able to relate to them. Thats all great, but science fiction is written by us for us, so, you have to relate a little, or who would read it.
They also spent some time on television sci fi, mainly disparaging the amount of humanoid aliens and how this was unlikely.... duh... but actors only come in human shape. sorry... but int he star trek universe it was okay since 10 million years ago or some such we were seeded by some other race. But no mention of the alien/human hybrid that run rampant, breed true in the second generation and are frankly bad science... we would be more genetically compatable with our ape cousins, but I have yet to see a human/chimp baby.
I wont even talk about the writing gimmick of the tourist bacteria that opened each chapter, since I found it condescending and quit reading it.
They also spent some time on television sci fi, mainly disparaging the amount of humanoid aliens and how this was unlikely.... duh... but actors only come in human shape. sorry... but int he star trek universe it was okay since 10 million years ago or some such we were seeded by some other race. But no mention of the alien/human hybrid that run rampant, breed true in the second generation and are frankly bad science... we would be more genetically compatable with our ape cousins, but I have yet to see a human/chimp baby.
I wont even talk about the writing gimmick of the tourist bacteria that opened each chapter, since I found it condescending and quit reading it.
August 31, 2024
A bit disappointing. Cohen and Stewart are professional scientists, respectively biologist and mathematician. They have some strong opinions about what they consider the traditional discussions of possible extraterrestrial life and in the early chapters come on a bit too combatively, then back off in later pages.
They take easy swipes at Star-Trek style humanoids, and at conservatism among professional "exobiologists", whom they accuse of being astronomers trying to practise biology without a licence. Cohen and Stewart decry the use of the Drake equation beyond its untended scope, and simplistic interpretations of Habitable Zones that ignore such factors as the density and composition of an atmosphere.
They introduce some useful ideas: "extelligence"—roughly the material parts of our culture that facilitate learning--and the distinction between between "parochials" (such as chlorophyl, the pentadactyl limb, perhaps DNA) and "universals" (photosynthesis, jointed limbs, eyes, flight . . . ). They make some interesting points about biology—species that can determine their sex; the fact that our our nose is above our mouth and therefore our food-intake and air-intake tubes have to cross is an unhappy consequence of the way the plumbing was organised in the first lung-fish to settle on land.
Still for all their enthusiasm and conviction that life is waiting out there, the authors have to accept that the possible refuges for extraterrestrial life in the solar system are shrinking. Mars and Venus have left the list. Titan, one of their suggestions, now seems to have followed. Only Europa's subsurface ocean seems a credible candidate—and it's likely to remain that way for a few decades, before any probes are able to investigate it. And among other stars, so far no hint of anything resembling biology or technology. Cohen and Stewart have produced a book that like its subject matter is heavy on speculation and badly limited by the lack of actual evidence.
They take easy swipes at Star-Trek style humanoids, and at conservatism among professional "exobiologists", whom they accuse of being astronomers trying to practise biology without a licence. Cohen and Stewart decry the use of the Drake equation beyond its untended scope, and simplistic interpretations of Habitable Zones that ignore such factors as the density and composition of an atmosphere.
They introduce some useful ideas: "extelligence"—roughly the material parts of our culture that facilitate learning--and the distinction between between "parochials" (such as chlorophyl, the pentadactyl limb, perhaps DNA) and "universals" (photosynthesis, jointed limbs, eyes, flight . . . ). They make some interesting points about biology—species that can determine their sex; the fact that our our nose is above our mouth and therefore our food-intake and air-intake tubes have to cross is an unhappy consequence of the way the plumbing was organised in the first lung-fish to settle on land.
Still for all their enthusiasm and conviction that life is waiting out there, the authors have to accept that the possible refuges for extraterrestrial life in the solar system are shrinking. Mars and Venus have left the list. Titan, one of their suggestions, now seems to have followed. Only Europa's subsurface ocean seems a credible candidate—and it's likely to remain that way for a few decades, before any probes are able to investigate it. And among other stars, so far no hint of anything resembling biology or technology. Cohen and Stewart have produced a book that like its subject matter is heavy on speculation and badly limited by the lack of actual evidence.
July 28, 2019
What Does A Martian Look Like?
Nothing like YOU imagine, especially if you are (sic!) Not Someone Who Consulted With Us or, worse, a Female Writer Who Loves Cats.
There was some brilliant stuff here, sure, but in the end, the authors come off as a literary collab equivalent of BBC's Sherlock, sweeping into your brain to say Shut Up, Anderson!
Somehow I have a hard time imagining Sir Terry writing a How Does Storytelling Work?, Especially If It's Not By Me Or My Mate Neil.
But of course Storytelling is not a Hard Science.
Nothing like YOU imagine, especially if you are (sic!) Not Someone Who Consulted With Us or, worse, a Female Writer Who Loves Cats.
There was some brilliant stuff here, sure, but in the end, the authors come off as a literary collab equivalent of BBC's Sherlock, sweeping into your brain to say Shut Up, Anderson!
Somehow I have a hard time imagining Sir Terry writing a How Does Storytelling Work?, Especially If It's Not By Me Or My Mate Neil.
But of course Storytelling is not a Hard Science.
August 1, 2021
This book is a bit of a mess. Certain concepts are expounded and pontificated on incessantly, the alleged subjects of chapters are lost in constant digressions and diatribes, sentences often meander confusingly, contradictions appear regularly, and errors crop up throughout (particularly the egregious misrepresentation of the age and lifespan of the sun)
While this wasn't what I would call enjoyable, it was reasonably interesting, if you have the patience to pick through the stream of consciousness to piece together the more coherent perspectives, philosophies and conjectures offered. This should be read with a skeptical and well-informed eye, so as to not be taken in by some of their more childish "open-mindedness," in particular their frequent dismissal of the probability of carbon and aerobic chauvinism in complex lifeforms throughout the universe, completely glossing over the reasons for these expectations.
For good, generally clearer, and I would say more grounded material on the subjects outlined here, I would recommend starting with The Living Cosmos by Impey, Life in Darwin's Universe by Bylinsky, Civilized Life in the Universe by Basalla, and Extraterrestrial Civilizations by Asimov before broaching What Does a Martian Look Like.
While this wasn't what I would call enjoyable, it was reasonably interesting, if you have the patience to pick through the stream of consciousness to piece together the more coherent perspectives, philosophies and conjectures offered. This should be read with a skeptical and well-informed eye, so as to not be taken in by some of their more childish "open-mindedness," in particular their frequent dismissal of the probability of carbon and aerobic chauvinism in complex lifeforms throughout the universe, completely glossing over the reasons for these expectations.
For good, generally clearer, and I would say more grounded material on the subjects outlined here, I would recommend starting with The Living Cosmos by Impey, Life in Darwin's Universe by Bylinsky, Civilized Life in the Universe by Basalla, and Extraterrestrial Civilizations by Asimov before broaching What Does a Martian Look Like.
May 10, 2020
I've had this book for 12 years and only made time lately to read it. Full of really interesting information even though it's a little out of date in some regards, the basis of their argument is still sound and it broadens the concept of life well beyond what one might expect.
Might be a bit tough to read if you've no head for chemistry or biology but I think for the most part they make it very understandable.
Might be a bit tough to read if you've no head for chemistry or biology but I think for the most part they make it very understandable.
April 2, 2024
Interesting thought experiment on aliens, and what they might be like - an enjoyable read to broaden your mind on the possibilities "out there", whilst pointing out some of the more "exotic" life forms right here on earth. Enjoyed the sci-fi book summaries too and might pick out a couple of them for future reading. Did feel a bit ranty at times though, the writers clearly have a bone to pick with those advocating a narrow human-like view for aliens! Could hence have even a bit more concise.
December 6, 2016
What does a Martian Look Like? sets out to do something seemingly impossible: to scientifically describe something we have never seen. The question it asks is what we can know about extraterrestrial life. Of course, we have never found any of that. And yet, Jack Cohen and Ian Stewart also argue against imagining it will be just like life on Earth.
So what can they even say in this book? Mainly that we need to speculate, but speculate wisely; taking into account all that we really know, and seeing what follows logically, instead of getting trapped in what our imaginations naturally tell us.
I got to know the authors first from their collaboration with Terry Pratchett on The Science of Discworld, a work half allegorical fiction and half popular science. Nowadays, I will mention them if asked about my favourite philosopher, even though they're not officially philosophers. Jack Cohen is a biologist, Ian Stewart is a mathematician, and together they write about complex systems theory. They possess both an acute, fascinating scientific vision and an entertaining, slightly quirky way of writing. This book is no exception.
Cohen and Stewart contrast their approach, which they call "xenoscience", with traditional "astrobiology". Astrobiology in this sense assumes that life in the rest of the universe must be very much like life on Earth, and so, for example, if we are to find any, we must look for planets just like ours. By contrast, this book argues that life could (for all we know) be based on something completely different than Earthly chemistry, as long as it can support the basics, like reproduction and evolution by natural selection. The authors point out that even less-known life on Earth does things that some astrobiologists would consider impossible. What looks to us like favourable conditions for life, like having water and oxygen around, could look impossibly hostile to some lifeform that evolved elsewhere. It's only vital for us because we evolved here. Since we've seen no alien life, we don't actually know that it could thrive in a totally different environment -- but we certainly don't know that it couldn't.
Cohen and Stewart also contrast their approach with naïve depictions of aliens in science fiction and accounts of alleged real encounters with them. In fact, they spend quite a lot of time discussing why these depictions only betray our lack of imagination. I agree that it's necessary for them to do this -- you can't explain how a thing really is if the person you're telling it has the wrong idea to begin with and you never explain why it's wrong. Besides, it's fun and interesting. So they explain why we're not to expect any cat people or little grey men. Speaking of science fiction, though, they also look at examples of different levels of credibility. The believable ones tend to be the most alien, but some of those don't work either.
As I said above, Cohen and Stewart teach us to speculate, but speculate wisely. The way they put it, you could expect alien life to be practically anything... except that many specific ideas won't work. There has to be a way something could evolve in the first place. No-one can say what real aliens will be like exactly, but the authors are able to give meaningful limits to speculation based on the distinction between universals and parochials: universally useful features for life -- like wings for flying or eyes for seeing, provided there's air to fly in or radiation to see, of course -- and things that just happen to be like that because of evolutionary history, like our having five fingers. Just think of how sharks and dolphins have evolved into about the same shape for similar purposes, but their tails move in different directions because dolphin ancestors were running land animals in between. Based on this, the authors make many surprising but entirely logical observations about what is possible. I was amused and intrigued by the observation that you would never expect any aliens to have their nose above their mouths, because that seemingly natural arrangement is something we only have because all land vertebrates have descended from a particular species of fish that left our airways inconveniently crossing our foodways.
What Does a Martian Look Like? is very imaginative, but in a way that only makes it more rigorously reasoned; the creativity and imagination ensure that lack of imagination does not prevent us from seeing what is really logically possible. It's entertaining and absolutely fascinating, not only as a study in xenobiology but also in human psychology, popular fiction, and in the principles of evolution. It's also highly recommended for anyone planning to write at all realistic fiction featuring aliens. Cohen and Stewart are simultaneously able to imagine the truly alien -- and yet to be critical about what ideas could really be realised.
So what can they even say in this book? Mainly that we need to speculate, but speculate wisely; taking into account all that we really know, and seeing what follows logically, instead of getting trapped in what our imaginations naturally tell us.
I got to know the authors first from their collaboration with Terry Pratchett on The Science of Discworld, a work half allegorical fiction and half popular science. Nowadays, I will mention them if asked about my favourite philosopher, even though they're not officially philosophers. Jack Cohen is a biologist, Ian Stewart is a mathematician, and together they write about complex systems theory. They possess both an acute, fascinating scientific vision and an entertaining, slightly quirky way of writing. This book is no exception.
Cohen and Stewart contrast their approach, which they call "xenoscience", with traditional "astrobiology". Astrobiology in this sense assumes that life in the rest of the universe must be very much like life on Earth, and so, for example, if we are to find any, we must look for planets just like ours. By contrast, this book argues that life could (for all we know) be based on something completely different than Earthly chemistry, as long as it can support the basics, like reproduction and evolution by natural selection. The authors point out that even less-known life on Earth does things that some astrobiologists would consider impossible. What looks to us like favourable conditions for life, like having water and oxygen around, could look impossibly hostile to some lifeform that evolved elsewhere. It's only vital for us because we evolved here. Since we've seen no alien life, we don't actually know that it could thrive in a totally different environment -- but we certainly don't know that it couldn't.
Cohen and Stewart also contrast their approach with naïve depictions of aliens in science fiction and accounts of alleged real encounters with them. In fact, they spend quite a lot of time discussing why these depictions only betray our lack of imagination. I agree that it's necessary for them to do this -- you can't explain how a thing really is if the person you're telling it has the wrong idea to begin with and you never explain why it's wrong. Besides, it's fun and interesting. So they explain why we're not to expect any cat people or little grey men. Speaking of science fiction, though, they also look at examples of different levels of credibility. The believable ones tend to be the most alien, but some of those don't work either.
As I said above, Cohen and Stewart teach us to speculate, but speculate wisely. The way they put it, you could expect alien life to be practically anything... except that many specific ideas won't work. There has to be a way something could evolve in the first place. No-one can say what real aliens will be like exactly, but the authors are able to give meaningful limits to speculation based on the distinction between universals and parochials: universally useful features for life -- like wings for flying or eyes for seeing, provided there's air to fly in or radiation to see, of course -- and things that just happen to be like that because of evolutionary history, like our having five fingers. Just think of how sharks and dolphins have evolved into about the same shape for similar purposes, but their tails move in different directions because dolphin ancestors were running land animals in between. Based on this, the authors make many surprising but entirely logical observations about what is possible. I was amused and intrigued by the observation that you would never expect any aliens to have their nose above their mouths, because that seemingly natural arrangement is something we only have because all land vertebrates have descended from a particular species of fish that left our airways inconveniently crossing our foodways.
What Does a Martian Look Like? is very imaginative, but in a way that only makes it more rigorously reasoned; the creativity and imagination ensure that lack of imagination does not prevent us from seeing what is really logically possible. It's entertaining and absolutely fascinating, not only as a study in xenobiology but also in human psychology, popular fiction, and in the principles of evolution. It's also highly recommended for anyone planning to write at all realistic fiction featuring aliens. Cohen and Stewart are simultaneously able to imagine the truly alien -- and yet to be critical about what ideas could really be realised.
November 16, 2012
If you can overlook the pop-science-y title, and can humour the authors on a few relatively harmless indulgences (an overeagerness to point out sci-fi mistakes; quirky, disposable passages of fiction at the start of each chapter), this is a fascinating read.
Stewart and Cohen use their combined biological and mathematical expertise to offer some well-researched and justified optimism. Life, they argue, ought to emerge from any complex chemistry. And complex chemistry is effectively just a matter of simple chemistry and time. Either life is unique to us, or it's *exceptionally* common. Especially if we're willing to broaden our definition of what life actually is.
With nothing but Earth examples to go on, they take some very interesting detours along the way, including the bizarre life forms hidden away on our own planet, and the impossibility of understanding other species' mindsets,
There were a couple of genuine epiphany moments and I left feeling more thrilled about the universe than when I started. As far as I'm concerned, that's the definition of a great science book.
Stewart and Cohen use their combined biological and mathematical expertise to offer some well-researched and justified optimism. Life, they argue, ought to emerge from any complex chemistry. And complex chemistry is effectively just a matter of simple chemistry and time. Either life is unique to us, or it's *exceptionally* common. Especially if we're willing to broaden our definition of what life actually is.
With nothing but Earth examples to go on, they take some very interesting detours along the way, including the bizarre life forms hidden away on our own planet, and the impossibility of understanding other species' mindsets,
There were a couple of genuine epiphany moments and I left feeling more thrilled about the universe than when I started. As far as I'm concerned, that's the definition of a great science book.
Read
May 19, 2007I loved this book. It's an interesting, thorough, thoughtful look at what alien life might be like, with the added bonus of discussing examples from sci-fi (thus expanding my booklist :). While I disagreed with the authors sometimes, that made it all the more fun to try and poke holes in their arguments.
October 11, 2013
This was hard going. I was expecting more of a guide for writers. It certainly gives me something to think about. Many of the ideas are complicated. I admit I was lost in places. A good read for the more scientifically minded.
July 29, 2014
I chose this book to help me design an extraterrestrial species in a book I'm writing. It was not much help in that regard, but did have some interesting thoughts on the possibilities and makeup of extraterrestrial life.
August 3, 2012
Lots of fun but I could have done with even more in-depth and greater explanation as to why this,that and other might be possible but I'm still going to buy it and read it again!
Currently reading
March 31, 2011Enormously enjoyable so far.
August 17, 2016
Highly refinded brain fuel, this book contains a little philosophy, a lot of science, and an inexpliciable disdain of koalas.
Displaying 1 - 14 of 14 reviews