This Is Life
A Journey from Inside Your Body to Beyond Earth
This Is Life
A Journey from Inside Your Body to Beyond Earth
Christophe Galfard, acclaimed author of the international bestseller The Universe in Your Hand, takes readers on an extraordinary journey across time and space—from the origins of Earth’s life to the search for extraterrestrials.
What is life? In this majestic book, Christophe Galfard, celebrated author and former graduate student of Stephen Hawking, takes us on a wonder-filled voyage to answer this question. He guides us from our planet’s birth and the mysterious bacteria that lived billions of years ago, through the extreme evolutionary turns that saw dog-sized sea scorpions and trees covered in scales, to the visionary discoveries of the past two centuries that have allowed us to understand human bodies and imagine alien ones.
With Galfard as our guide, readers go back in time to Earth’s origins, swim inside our bloodstream, and sail in space beyond the safety of our terrestrial haven. We experience the birth of Earth, the demise of the dinosaurs, and the possible creation of life in outer space. This Is Life offers a glimpse of other worlds detected only in recent years, beyond the Solar System, where life could be thriving. The end of the book’s journey signals new beginnings, and we are left with the overwhelming sense that, as members of a long line of living creatures, we belong to a reality far greater and more complex than we ever imagined.
Through brilliant storytelling and delightful humor, Galfard connects the latest scientific discoveries and makes the secrets of the living world accessible to all. This Is Life will transform the way you see the world and your place in it.
400 pages | 27 halftones | 6 x 9 | © 2026
Biological Sciences: Evolutionary Biology, Paleobiology, Geology, and Paleontology
Earth Sciences: General Earth Sciences
Reviews
Table of Contents
List of Illustrations
Foreword
Part 1: Evolution
The curse • Why alien fish most probably don’t fly • What is true for birds is true for us • An unexpected parcel • The ear that shouldn’t exist • On the advantages of being ethereal • Little Green Men signal number 1 • A Tree of Life • What life is
Part 2: An Extinction
Where digging leads • And you thought you were having a bad day . . . • Bad things usually come in a series • What to do when all hell breaks loose • If you’re still around, well done • A planetary facelift • An ocean made of rocks • How a meteorite can send you to hospital
Part 3: The History of the Earth
The birth of a cosmic couple • After hell comes hell • The relativity of boredom • An explosion that shouldn’t have been • A little summary • A long-gone alien world • Land ho! • Turning green • The time of the giant insects • Two holes in the skull • The day the ground opened up
Part 4: A Journey Within
The basic building block • Beware of yellow robots • Introducing the yellow robot • There’s mystery in your hand • Journey inward • Bubbles up and down • Compartments, everywhere • To see the invisible • Why people consider you to be a CHNOPS • The nucleic acids • The art of making chains • The message from within • The headquarters • The birth of memory • DNA • A universal alphabet • The code of life • A 150,000-year-long journey • From life to life • Humans are waterfalls • The making of you, part one • Power, the female link • The most amazing cycle • Something deep • Sometimes, even dating apps can’t help • The making of you, part two: epigenesis
Part 5: Domains of Life
More than a summary • Three is a magic number, even for a tree • A conundrum • Healthy smokers • What we are a part of • Introducing LUCA • Horizontal gene transfer • Poisons • And now for some whisky • A photo shoot • A parallel world • Genetic engineering
Part 6: Looking for an Origin
Spontaneous generation • A day in the life of . . . • Spontaneous generation revisited • Before DNA • Extreme survival • Destinations • Distant encounters of the third kind • Where are they?
Epilogue
Acknowledgements
Sources
Index