A circle of yellow leaves with the words " what is life ?" written in it.

What is Life: Five Great Ideas in Biology by Paul Nurse 2020

Nurse, a British scientist who won the Nobel Prize in 2001 for his work in sorting out the cell cycle in yeast, has written a fine little book.

Along with the 1944 book by the Nobel Prize winning physicist Erwin Schrodinger and the 1947 book by the biologist J.B.S. Haldane which both shared this book’s title, Nurse tries to figure out what it is that differentiates ‘life’ from ‘non-life’ on earth.  Picking up on the theme in Carl Zimmer’s Life’s Edge which I reviewed last month, Nurse takes a more objective, scientific view and boils down all the scientific advances over the last century to five great ideas:  the cell, the gene, evolution and natural selection, life as chemistry, and life as information.  He does a fine job with his analysis and examples.  As a physician and ‘scientist’, I found the chapters on the cell and the gene a bit too basic, but the book picked up speed and interest, however, as Nurse made the case that natural selection is perhaps the sine qua non for ‘life’.  His chapters on chemistry and information management helped me appreciate for the first time, how complex and wondrous are the workings of the cell, a tiny world unto itself where thousands of simultaneous chemical reactions are taking place compartmentalized and managed by proteins which have been synthesized by the DNA/RNA axis.

Nurse comes to the conclusion that life must have three principles:  the ability to evolve through natural selection; have a form that bounds and separates it from the outside world; exist as chemical, physical, informational machine.  He summarizes his awe for this system in the following sentence:  “I cannot imagine a more elegant solution: different configurations of linear carbon polymers generate both chemically stable information storage devices and highly diverse chemical activities.”  He is referring to DNA that is the nearly foolproof tool for replicating ourselves and proteins that catalyze the chemical reactions that enable us to move, breathe, and do all the other ‘life’ things.

If that sentence prods your curiosity rather than befuddles you, dive into this slim volume.  If nothing else, you will end up with a greater degree of respect and awe for that body you’ve been inhabiting for so many years without really thinking about it.