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I, Mammal: The Story of What Makes Us Mammals
Humans are mammals. Most of us appreciate that at some level. But what does it mean for us to have more in common with a horse and an elephant than we do with a parrot, snake or frog?
After a misdirected football left new father Liam Drew clutching a uniquely mammalian part of his anatomy, he decided to find out more. Considering himself as a mammal first and a human second, Liam delves into ancient biological history to understand what it means to be mammalian.
In his humorous and engaging style, Liam explores the different characteristics that distinguish mammals from other types of animals. He charts the evolution of milk, warm blood and burgeoning brains, and examines the emergence of sophisticated teeth, exquisite ears, and elaborate reproductive biology, plus a host of other mammalian innovations. Entwined are tales of zoological peculiarities and reflections on how being a mammal has shaped the author's life.
I, Mammal is a history of mammals and their ancestors and of how science came to grasp mammalian evolution. And in celebrating our mammalian-ness, Liam Drew binds us a little more tightly to the five and a half thousand other species of mammal on this planet and reveals the deep roots of many traits humans hold dear.
After a misdirected football left new father Liam Drew clutching a uniquely mammalian part of his anatomy, he decided to find out more. Considering himself as a mammal first and a human second, Liam delves into ancient biological history to understand what it means to be mammalian.
In his humorous and engaging style, Liam explores the different characteristics that distinguish mammals from other types of animals. He charts the evolution of milk, warm blood and burgeoning brains, and examines the emergence of sophisticated teeth, exquisite ears, and elaborate reproductive biology, plus a host of other mammalian innovations. Entwined are tales of zoological peculiarities and reflections on how being a mammal has shaped the author's life.
I, Mammal is a history of mammals and their ancestors and of how science came to grasp mammalian evolution. And in celebrating our mammalian-ness, Liam Drew binds us a little more tightly to the five and a half thousand other species of mammal on this planet and reveals the deep roots of many traits humans hold dear.
336 pages, Paperback
Published January 1, 2018
48 people are currently reading
1121 people want to read
About the author
Liam Drew
8 books15 followersLiam Drew is a writer and features journalist. His work covers neuroscience, biomedical research and evolutionary biology. He is regular contributor to Nature and its sister journals and he has written for New Scientist, Slate, The Guardian, The Independent, Aeon, Quanta, Knowable, BBC Wildlife and Reader's Digest. I, Mammal: The Story of What Makes us Mammals (Bloomsbury, 2017) was his first book. His second was The Brain Book (DK Publishing, 2021) an introduction to the brain for 5-9 year olds. Before writing, Liam was a neurobiologist. He got his PhD from University College London and worked for eight years at Columbia University, New York. He lives in Kent, UK with his wife and daughters.
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December 23, 2020Update 1 For some, science will forever be an unknown country, "The platypus is more evidence for the amazing intelligence of God's design. Truly only a super-Intelligent Designer could make such an amazing combination of mammalian and reptilian features in a single creature." Creationwiki. The platypus is an extremely odd mammal. It in many ways bridges the gap between reptiles and mammals and thus is constantly referred to in this book. It helps explain evolution, not that someone up there in the sky is sifting through body parts and sticks a disparate bunch of them together, perhaps for fun. However, platypus babies are the cutest little things I've ever seen. Next to kittens.
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Conundrum Balls. Why do some mammals have a scrotum and some don't? Elephants don't, vervet monkeys have very pretty bright blue balls, seals don't but sea lions do some of the time (in mating season), dolphins don't and neither do manatees, but Right whales have the biggest in the world 900 Kg .
Most mammals that have testicles have them hanging behind the penis, but marsupials have them in front and yellow-bellied house bats have them behind the anus. There are many theories why some mammals have visible balls and others keep them in their bodies, no one really knows.
And there was me thinking the simple definition of a mammal was has hair, produces milk and bears live young. Apart, that is, from echidnae and platypuses which lay eggs and secrete milk through their skin rather than nipples, someone's always got to be different, right?
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It's no good, I can't get away from science books. I really tried yesterday and dnf'd the patronising and awfully-badly written (imnsho) For the Benefit of Those Who See: Dispatches from the World of the Blind and then the preachy, self-righteous anti-Mormon The Mormon Missionaries: An Inside Look at Their Real Message by an ex-Mormon, a born-again Christian who had seen the light. They both sounded good, but life is too short for books I'm not going to either enjoy or learn something from.
This started off great with a story of the author's premature baby and expressing milk and their lives being ruled by the thump and whirr of an electronic pumping machine. I had that too. My son was small, 5.75 lb and couldn't latch on because my breasts had gone up to 42G which kind of suffocated him but like the author I was determined my son would have breast milk. Then we get on to a list of countries and no. of mammals in them and he made that sound interesting, so I have a good feeling about this book.
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Conundrum Balls. Why do some mammals have a scrotum and some don't? Elephants don't, vervet monkeys have very pretty bright blue balls, seals don't but sea lions do some of the time (in mating season), dolphins don't and neither do manatees, but Right whales have the biggest in the world 900 Kg .
Most mammals that have testicles have them hanging behind the penis, but marsupials have them in front and yellow-bellied house bats have them behind the anus. There are many theories why some mammals have visible balls and others keep them in their bodies, no one really knows.
And there was me thinking the simple definition of a mammal was has hair, produces milk and bears live young. Apart, that is, from echidnae and platypuses which lay eggs and secrete milk through their skin rather than nipples, someone's always got to be different, right?
____________________
It's no good, I can't get away from science books. I really tried yesterday and dnf'd the patronising and awfully-badly written (imnsho) For the Benefit of Those Who See: Dispatches from the World of the Blind and then the preachy, self-righteous anti-Mormon The Mormon Missionaries: An Inside Look at Their Real Message by an ex-Mormon, a born-again Christian who had seen the light. They both sounded good, but life is too short for books I'm not going to either enjoy or learn something from.
This started off great with a story of the author's premature baby and expressing milk and their lives being ruled by the thump and whirr of an electronic pumping machine. I had that too. My son was small, 5.75 lb and couldn't latch on because my breasts had gone up to 42G which kind of suffocated him but like the author I was determined my son would have breast milk. Then we get on to a list of countries and no. of mammals in them and he made that sound interesting, so I have a good feeling about this book.
November 30, 2017
It's rare that a straightforward biology book (with a fair amount of palaeontology thrown in) really grabs my attention, but this one did. Liam Drew really piles in the surprising facts (often surprising to him too) and draws us a wonderful picture of the various aspects of mammals that make them different from other animals.
More on this in a moment, but I ought to mention the introduction, as you have to get past it to get to the rest, and it might put you off. I'm not sure why many books have an introduction - they often just get in the way of the writing, and this one seemed to go on for ever. So bear with it before you get to the good stuff, starting with the strange puzzle of why some mammals have external testes.
It seems bizarre to have such an important thing for passing on the genes so precariously posed - and it's not that they have to be, as it's not the case with all mammals. Drew mixes his own attempts to think through this intriguing issue with the historical debates over it, leading up to the latest thinking.
This is the broad approach Drew tends to take in most of the chapters, whether we're looking at the jaw bone (apparently the most distinctive aspect of mammals), the senses, being warm blooded (but we're not allowed to call it that), hairiness or lactation. That last item had one of the most striking statistics amongst the 'Wow!' facts Drew gives us - that one species of whale when suckling young produces about a quarter of a tonne of milk a day.
Another delightful feature that recurs through the book is the duck billed platypus. After diving into this weird and wonderful creature in some detail early on, they keep cropping as their odd position on the mammalian family tree makes them an inevitable recurring reference point. And the more you read about the platypus, the more you love it.
Only two things were less than perfect. A couple of chapters fell into the Feynman Trap by spending too much time naming things and losing steam a little on the narrative, but these weren't too much of an issue. The other problem for me is a personal one. Drew uses his children and details of family life, particularly of the premature birth of his first child, far too much for me. I know some people (and publishers) love all these personal details, but I found it mildly nauseating - however, I'm sure that's just me.
Overall, this is a brilliant book, particularly if, like me, you know relatively little of biology or what makes mammals, erm, mammals. It's light enough to be enjoyable but detailed enough to satisfy the most fact-driven reader. Recommended.
More on this in a moment, but I ought to mention the introduction, as you have to get past it to get to the rest, and it might put you off. I'm not sure why many books have an introduction - they often just get in the way of the writing, and this one seemed to go on for ever. So bear with it before you get to the good stuff, starting with the strange puzzle of why some mammals have external testes.
It seems bizarre to have such an important thing for passing on the genes so precariously posed - and it's not that they have to be, as it's not the case with all mammals. Drew mixes his own attempts to think through this intriguing issue with the historical debates over it, leading up to the latest thinking.
This is the broad approach Drew tends to take in most of the chapters, whether we're looking at the jaw bone (apparently the most distinctive aspect of mammals), the senses, being warm blooded (but we're not allowed to call it that), hairiness or lactation. That last item had one of the most striking statistics amongst the 'Wow!' facts Drew gives us - that one species of whale when suckling young produces about a quarter of a tonne of milk a day.
Another delightful feature that recurs through the book is the duck billed platypus. After diving into this weird and wonderful creature in some detail early on, they keep cropping as their odd position on the mammalian family tree makes them an inevitable recurring reference point. And the more you read about the platypus, the more you love it.
Only two things were less than perfect. A couple of chapters fell into the Feynman Trap by spending too much time naming things and losing steam a little on the narrative, but these weren't too much of an issue. The other problem for me is a personal one. Drew uses his children and details of family life, particularly of the premature birth of his first child, far too much for me. I know some people (and publishers) love all these personal details, but I found it mildly nauseating - however, I'm sure that's just me.
Overall, this is a brilliant book, particularly if, like me, you know relatively little of biology or what makes mammals, erm, mammals. It's light enough to be enjoyable but detailed enough to satisfy the most fact-driven reader. Recommended.
June 18, 2018
Um ótimo passeio pela evolução e pelas características dos mamíferos. O livro passa pelo começo dos mamíferos e uma série de características, mais centrado na reprodução. Passa pelos hormônios, pelas gônadas, pela fecundação, gestação, nascimento e desenvolvimento. Terminando com o cérebro e comportamento.
Me trouxe muita informação nova e legal, com bom humor e bem escrito. De fazer um biólogo feliz.
Me trouxe muita informação nova e legal, com bom humor e bem escrito. De fazer um biólogo feliz.
April 12, 2024
“Mammalian-ness is only one answer to the question of how to live. What makes it interesting is not that it is better, but that it is ours.”
1 Sentence Summary: Everyone knows that we are mammals, but what is a mammal, and where did they come from?
My Thoughts: Why do I feel like this 300 page book about what a mammal is just made more confused about what exactly a mammal is?
Overall, I enjoyed this. Some parts kind of dragged, but the writing style was entertaining and easy to follow. It’s written in more of a conversational than strictly academic tone.
Some fun facts:
- Platypuses can sense electricity through their bills
- Some birds produce a milk-like substance that they feed to their babies, and both parents (male and female) produce it!
- Birds are technically reptiles
- The high-pitched mouse squeaks we hear are actually at the lowest end of the frequencies of sounds they make—most of their communication is at a frequency too high for us to hear
- It used to be thought that humans had 48 chromosomes, until “In 1956, the number of chromosomes in a human cell was finally corrected to 46.” After the study was published showing we only had 46, “numerous researchers confessed to having already counted 46 but were too embarrassed to say so.” HAHA.
- We’re called mammals because of a female trait, the mammary glands.
A quote that almost made me burst out laughing while reading this at work:
“The uniqueness of this form of sex is owed to the females, for, in strict anatomical terms, the vagina is a purely mammalian invention. I once met someone so taken with this fact, she wanted to write a song called Only Mammals Have Vaginas. I explained that this was only true according to a quite precise technical definition of a vagina, and other female animals had functionally similar organs, but she remained convinced it would make a catchy song.”
Some not so fun facts:
- We’re living through a global biodiversity crisis, often termed the sixth mass extinction.
- In October 2018, the World Wildlife Fund released its biannual Living Planet Report, which stated that across all vertebrates the average species was 60 per cent less abundant than it was in 1970.
- A 2018 Danish study concluded that for mammalian diversity to recover from human interference would take at least 3-7 million years.
- Another study, projecting 200 years into the future, saw nothing in current population trends for elephants and rhinos, hippos, giraffes and other large terrestrial mammals to suggest they'd still be around. By then, cows may well be the largest land mammals left alive.
- Humans can be viewed as super-predators. Our presence causes wild mammals to always be on guard, constantly full of stress hormones, spending a huge amount of their time in a state of hyper-vigilance.
We are part of this Earth and we need to respect and care for the other life that inhabits our planet with us.
Recommend to: People interested in animals, specifically mammals, and their evolution.
June 10, 2018
Absolutely loved this book. Liam Drew is one of those writers who, if he wrote a grocery list, I'd read it. Incredibly talented man with a very engaging voice.
August 25, 2018
Dik-dik males are monogamous but do not guard, feed or teach their young. *The name dik-dik appears to echo a sound the antelopes make, rather than being a comment on this apparent neglect.
February 7, 2023
Took me 2 years to finish this but it was so interesting! Made me laugh out loud on more than one occasion, and I learned a lot
October 10, 2018
Many people say they "believe" in the Theory of Evolution but how many really know how it works?
This book shows how the different hypothesis are created, tested and debated. Most fascinating, the author shows the gaps in our knowledge, the mysterious aspects of mammals that scientists can't explain. I found the in-depth history of the changing theories sometimes tiresome. I just wanted to know what the science community thinks NOW. But I'm glad that he writes about how scientists change their theories, get things wrong and rework old ideas. This is a great book for learning about how science works.
This book shows how the different hypothesis are created, tested and debated. Most fascinating, the author shows the gaps in our knowledge, the mysterious aspects of mammals that scientists can't explain. I found the in-depth history of the changing theories sometimes tiresome. I just wanted to know what the science community thinks NOW. But I'm glad that he writes about how scientists change their theories, get things wrong and rework old ideas. This is a great book for learning about how science works.
August 7, 2019
I enjoy learning new things about the natural world around us. Liam Drew's book expands on the things I was taught about what makes mammals unique. He outlines the way that evolution has worked on different species to create the differences (and similarities) we observe in the world. I enjoyed his humor through most of the book. I also got lost in some of the more technical explanations. Overall, it was a fun, informative read, with real information balanced by entertaining prose and amusing phrasings.
August 16, 2020
“I, Mammal” is an informative, easy to read examination of the traits that define mammals and show where humans fit into that family tree. The chapters are organized generally by anatomical parts and traces their history through the eons. Author Liam Drew compares fossil remains with modern life forms to try to determine when certain species branched off from others and why. He frequently compares the animal types such as reptiles, birds and mammals to determine why some dominated the earth at sometimes and relinquished their dominion to others.
Although science is not my main interest, I found this to enhance my understanding of the transition of life forms over millions of years and left questions as to the current and future relationships of fauna in the future. I was particularly interested in the comparison of the calory needs and energy levels of endotherms (warm-blooded) versus ectotherms (cold-blooded). The news that crocodiles may only feed once a year was surprising. The suggestion that some animals rely more on sound than sight made sense, although I had not thought of it before. It also follows that those same animals may be dull shades because they do not detect colors very well. It brought back memories of my high school biology class. It was a worthwhile read and will encourage me to pick up other scientifically oriented books in the future. It may do the same for you.
I received a free copy of this book through the Amazon Vine Program
Although science is not my main interest, I found this to enhance my understanding of the transition of life forms over millions of years and left questions as to the current and future relationships of fauna in the future. I was particularly interested in the comparison of the calory needs and energy levels of endotherms (warm-blooded) versus ectotherms (cold-blooded). The news that crocodiles may only feed once a year was surprising. The suggestion that some animals rely more on sound than sight made sense, although I had not thought of it before. It also follows that those same animals may be dull shades because they do not detect colors very well. It brought back memories of my high school biology class. It was a worthwhile read and will encourage me to pick up other scientifically oriented books in the future. It may do the same for you.
I received a free copy of this book through the Amazon Vine Program
July 4, 2018
Most people don't give a second thought to what kind of animal we are. We just are. Liam Drew takes the time to point out some of the anomalous features of we mammals and delineates the evolutionary path that brought us here. For me the most fascinating part was the discussion of live birth and how the placenta essentially creates a hospitable environment for itself by chemically messing with the mother - causing mood changes, dietary changes, and physiological changes that would not be out of place in any science fiction alien invasion story.
November 6, 2017
Absolutely outstanding. A modern classic: warm, funny, erudite.
April 13, 2020
A wonderful book. I really enjoyed reading it and pondering mammalian attributes in humans and other animals.
September 21, 2021
I absolutely loved this - a fantastic read that really made me appreciate what it means to be mammalian. Liam tells an amazing personal story built around chapters that describe each of the mammalian features. Learned so much and couldn't put it down! I was lucky enough to meet the author at a conference too and he signed my copy, a thoroughly nice chap - and his presentation was as good as his book!
October 16, 2020
Decent read. Very detailed but not overly technical look at the evolutionary journey of mammals (people in particular). Has some funny parts and helps you understand what it means to be human (on a scientific and emotional level) a little bit more.
I'm giving it 4 stars but if Goodreads allowed half stars it would be a 3.5
I'm giving it 4 stars but if Goodreads allowed half stars it would be a 3.5
September 28, 2019
Mammals have several unique features seen nowhere else in the animal kingdom, still evolution tells us that mammals are continuous with other animals. Liam Drew systematically considers all of the mammalian traits and traces their evolutionary history into reptiles, fish or even further down. Starting with hanging testicles and ending with blown-up brains mammalian history is explained from an evolutionary and adaptive perspective. Some features are dealt with in quite some detail (brain structure), while others receive only superficial treatment (the urogenital system). Drew is obviously a darwinist and like many evolutionary biologists tends to exaggerate the awesome power of natural selection, while actually it is mutations and developmental reprogramming that do the job of evolution. The non-adaptive tinkering aspect of the evolutionary process I felt missing in this book. But Drew writes likes a novelist and intersperses his lectures on comparative zoology with personal stories on the mammalianness of his family members, a happy marriage and a great achievement.
February 7, 2018
4 1/2 stars. I probably won't go back to read it again.
A lot of interesting information about mammals and evolution. Fun to read. It surpised me a bit, halfway through the book, when I realized that the author was still discussing reproductive systems, human and otherwise. It wasn't long until the other themes began to be addressed. Lactation, hair, homeothermy, the bones of the inner ear. Things I hadn't even known that I didn't know.
A lot of interesting information about mammals and evolution. Fun to read. It surpised me a bit, halfway through the book, when I realized that the author was still discussing reproductive systems, human and otherwise. It wasn't long until the other themes began to be addressed. Lactation, hair, homeothermy, the bones of the inner ear. Things I hadn't even known that I didn't know.
March 21, 2018
Another interesting book from Bloomsbury Sigma. The series seems to have a raft of authors who not only write well, but also underlie their titles with humour- and not to the detriment of the subject. I'm hoping to read as many of the books in this series that I can.
August 28, 2022
This book was recommended to me by one of the staff at the University of Alberta, and after reading it I can confirm two things: 1) Platypuses are definitely out there on the weird end of the evolutionary tree. 2) Mammals are extremely interesting beasts, and I am quite glad the circumstances that brought the author to write this book happened, but at the same time I'm sorry that it did happen to him - that's gotta hurt!
Dr. Drew essentially takes the reader on quest to discover what makes a mammal, a mammal. In this book he deals with subjects such as why the male gonads are outside the body, the early investigations about what is a mammal, the role of the 'Y' chromosome in being male, sex in the mammal kingdom, the function of the placenta, nursing, how mammals learn to be caregivers, the mammalian family tree, and much more.
Now while some may consider this to be a very dry subject, Dr. Drew makes it well worth the read as he intersperses numerous examples, real life events, and a good deal spot-on humour to make it an enjoyable read.
I believe this book would make a wonderful supplementary text for any 1st year comparative anatomy course (at least one dealing with mammals), and would suggest that even if you aren't in school, you are a mammal (at least I assume you are), and this is the story of how you came to be what you are.
A great read!
Dr. Drew essentially takes the reader on quest to discover what makes a mammal, a mammal. In this book he deals with subjects such as why the male gonads are outside the body, the early investigations about what is a mammal, the role of the 'Y' chromosome in being male, sex in the mammal kingdom, the function of the placenta, nursing, how mammals learn to be caregivers, the mammalian family tree, and much more.
Now while some may consider this to be a very dry subject, Dr. Drew makes it well worth the read as he intersperses numerous examples, real life events, and a good deal spot-on humour to make it an enjoyable read.
I believe this book would make a wonderful supplementary text for any 1st year comparative anatomy course (at least one dealing with mammals), and would suggest that even if you aren't in school, you are a mammal (at least I assume you are), and this is the story of how you came to be what you are.
A great read!
November 15, 2017
Goalkeeper, neurobiologist and published science writer, Drew seems like the kind of guy that could turn his hand to anything and be successful. Luckily for us he turned his hand to pen and paper to author “I, Mammal”.
His work is a fascinating voyage of historical scientific discovery on the high-seas of mammalian evolution. Through the chapters we uncover the evolution of characteristics that make us mammals. Drew manages to distill the most poignant scientific theories whilst intertwining them with engaging personal anecdotes.
This collaboration of personal discovery and historical scientific journey strikes a great balance that makes for an absolutely fascinating read. I’m just left wondering what Drew will conquer next!
His work is a fascinating voyage of historical scientific discovery on the high-seas of mammalian evolution. Through the chapters we uncover the evolution of characteristics that make us mammals. Drew manages to distill the most poignant scientific theories whilst intertwining them with engaging personal anecdotes.
This collaboration of personal discovery and historical scientific journey strikes a great balance that makes for an absolutely fascinating read. I’m just left wondering what Drew will conquer next!
December 30, 2022
Perhaps more detail about mammalian evolution than the average person cares about, but I enjoyed it, especially the final two chapters. Much to think about, but I was particularly struck by his observation that the brain evolved in service to the body rather than the other way around. Since consciousness is seated in the brain, most of us think of the body as a vessel in service to the brain. It’s consistent with the arguments made in the last book I read before this one (Move: How the New Science of Body Movement Can Set Your Mind Free by Caroline Williams.) Will definitely be giving this some more thought…
September 7, 2020
Purchase I, Mammal here for just $10!
This is a very good science book that's entertaining and well-researched. Liam Drew takes us on a journey of how we became, and what it is to be, a mammal. Easy to read but scientifically rigorous, definitely recommended.
Alicia - The Book Grocer
This is a very good science book that's entertaining and well-researched. Liam Drew takes us on a journey of how we became, and what it is to be, a mammal. Easy to read but scientifically rigorous, definitely recommended.
Alicia - The Book Grocer
July 16, 2018
There’s a lot of interesting facts there, but I just can’t stand the long chapters about cells dividing and hormones being released… It just bores me to death. But it’s just me – there’s a high chance other really enjoy that and the book is well researched. I recommend it as long as you don’t mind long passages about cell biology.
January 19, 2024
Informative book on what traits make animals mammals and how similar or distant those can be from their closest relatives. The book has some humour and personal perspectives so it is not tottally dry and scientific. I learned some things about different animals, but was not blown away by the book overall.
January 29, 2019
3.5 stars. The topic is really interesting. It starts really well, but I'm afraid the writing becomes a little more difficult during the second half of the book. I would have really appreciated more figures, especially in the chapters about teeth.
July 13, 2020
I, Mammal is an entertaining book on evolution that marvels at our membership of this lactating, furry, warm-blooded group of animals. See my full review at https://inquisitivebiologist.com/2019...
January 30, 2019
Pretty dry at many parts, some very interesting facts strewn about in there, really disappointed overall though. Never really got into it like most other books.
September 5, 2020
3.5 stars. Lots of interesting facts, well written and a good organizational structure. Some sections more engaging than others.
November 4, 2023
Fascinating and mostly digestible. Neurological chapters were the hardest to follow, had to listen closely. Very human tale threaded through it. Liked it.
September 29, 2025
Very informative but too dense to be a fast read. More scholarly than expected.
Displaying 1 - 30 of 35 reviews