Critical Assessment

What did the author do well?

This book was jam packed with information. The book combines many fields, such as physiology, evolution, philosophy, and many more. The chapters were very thorough in explaining concepts to an unfamiliar audience. It was very clear that Ashcroft is a physiology professor at Oxford through the well explained physiology in understandable terms.

The book also had anecdotal stories and important photos. The incorporation of quotes from important figures throughout the book helped to visualize the different sickness or dangers associated with these extremes. Specifically, the  quote from a climber experiencing mountain sickness set a very clear image of what this sickness would feel like.

The organization of the book into the seven chapters provides a nice layout that touches on a wide range of extreme conditions, from the bottom of the ocean to outer-space. The inclusion of natives and their adaptations to these environments was much appreciated in the investigation of how some organisms can survive such extremes. It was also very useful comparing other species, such as birds in regard to flight and sperm whales in regard to the bends, as it gives a better understanding of what humans lack that prevent us from thriving in these situations.

What did the author do wrong?

Some parts of the book were a little too detailed, such as the chemical explanations of respiration and hemoglobin function. At points, this book reads more like a textbook chockfull of academic jargon.

Ashcroft also included personal anecdotes which were often unnecessary and even arrogant. For example, Ashcroft mentions how Robert Boyle developed his pressure x volume = constant law in “his Oxford laboratory, which lies not far from my own.”

I also do not believe the author did a great job at explaining the gender differences in regards to performance. In 2003, the IOC approved a guideline that a transgender athlete must have a reassignment surgery and at least two years of hormone therapy to compete. This book was published in 2000, so although this topic has picked up a lot of traction recently, it had already been a major topic of discussion. In the book, this section takes up only about a page and a half meanwhile performance enhancing drugs takes up almost 5 pages. I think the topic of gender differences in performance could have been greatly expanded on as it is a very important issue in society and education on this topic would be very beneficial for the public.

There were mention of some of the extremophile organisms having applications in cleaning up waste and toxins. This left me with questions of how it works, what is the current extent of use, what are side effects of this, and many more. I would have liked for the book to expand on the application of these organisms in cleaning up the environment.

Should you read this book?

If you enjoy extreme sports or are interested in physiology, you should read this book. There are mentions of these extreme sports, how your body is able to perform them, and the types of effects this has on your body. This book can serve as a warning for those who are on the fence for certain experiences, such as space exploration or climbing Mount Everest, and can serve as a guideline of what to do and what to expect when undertaking these experiences. For those curious about acclimatization and adaptation,  this is the book for you.

The book is particularly engaging because of the relevance of a lot of the material within it. It is easy to relate to and keeps the reader on their toes by exploring different situations, species, and time periods. There are many real world applications for this book, such as the cryopreservation of egg and sperm, that can satisfy your curiosity.

Regardless of your background in the topic, the book is written for anyone to understand. This book is both intriguing and enlightening. There are explanations for common experiences, such as ears popping on an airplane or feeling the urgent need to pee when going into the pool. This common experiences are then connected to more extreme experiences to bring the book full circle.

Educational highlights

One of the more interesting takeaways from this book that I learned was the necessity of water for life. There are organisms that can basically live in all types of conditions, such as those without oxygen that use hydrogen and carbon dioxide instead, but all organisms require water to grow and reproduce. It was fascinating to me that the question of ‘is there life on other planets’ is more a question of ‘where are there places with water’?

Another highlight was the keen observation that humans are better adapted to dry heat than humid heat. We see that humans have a large number of sweat glands which help with heat loss along with the slim and long anatomy and relative hairlessness. This is in parallel with fossil evidence suggesting that Homo sapiens originated in the hot plains of Africa.

A major misconception that was cleared up for me was the oxygen versus carbon dioxide regulation for breathing. Carbon dioxide is actually what controls breathing. When out of breathe, it is not because you need to breathe in more oxygen but rather to reduce the rising carbon dioxide concentration in the blood. This mechanism suggests that humans evolved at sea-level since the amount of oxygen in the lungs is much greater than needed when at sea-level.