Mathematics of Life: Unlocking the Secrets of Existence

341 Pages·2011·3.97 MB·English

by  Ian Stewart

Mathematics of Life
By the same author
Concepts of Modern Mathematics
Game, Set and Math
The Problems of Mathematics
Does God Play Dice?
Another Fine Math You’ve Got Me into
Fearful Symmetry (with Martin Golubitsky) Nature’s Numbers
From Here to Infinity
The Magical Maze
Life’s Other Secret
Flatterland
What Shape Is a Snowflake?
The Annotated Flatland Math Hysteria
The Mayor of Uglyville’s Dilemma
Letters to a Young Mathematician
Why Beauty Is Truth
How to Cut a Cake
Taming the Infinite: The Story of Mathematics
Professor Stewart’s Cabinet of Mathematical Curiosities
Professor Stewart’s Hoard of Mathematical Treasures
Cows in the Maze
with Terry Pratchett and Jack Cohen
The Science of Discworld
The Science of Discworld II: the Globe
The Science of Discworld III: Darwin’s Watch
with Jack Cohen
The Collapse of Chaos
Figments of Reality
Evolving the Alien/What Does a Martian Look Like?
Wheelers (science fiction) Heaven (science fiction)
Mathematics of Life
Unlocking the Secrets of Existence
Ian Stewart
First published in Great Britain in 2011 by
PROFILE BOOKS LTD
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London EC1R OJH
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Copyright © Joat Enterprises, 2011
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The right of Ian Stewart to be identified as the author of this work has been asserted by his estate in
accordance with the Copyright, Designs and Patents Act 1988.
All rights reserved. Without limiting the rights under copyright reserved above, no part of this publication
may be reproduced, stored or introduced into a retrieval system, or transmitted, in any form or by any
means (electronic, mechanical, photocopying, recording or otherwise), without the prior written permission
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A CIP catalogue record for this book is available from the British Library.
ISBN 978 184668 198 1
eISBN 978 184765 350 5
Export ISBN 978 184668 550 7
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Contents
Preface

1 Mathematics and Biology
2 Creatures Small and Smaller
3 Long List of Life
4 Florally Finding Fibonacci
5 The Origin of Species
6 In a Monastery Garden
7 The Molecule of Life
8 The Book of Life
9 Taxonomist, Taxonomist, Spare that Tree
10 Virus from the Fourth Dimension
11 Hidden Wiring
12 Knots and Folds
13 Spots and Stripes
14 Lizard Games
15 Networking Opportunities
16 The Paradox of the Plankton
17 What is Life?
18 Is Anybody Out There?
19 The Sixth Revolution
Notes
Acknowledgements
Index
Preface
Mathematical theory and practice have always gone hand in hand, from the time
primitive humans scratched marks on bones to record the phases of the Moon to
the current search for the Higgs boson using the Large Hadron Collider. Isaac
Newton’s calculus informed us about the heavens, and over the past three
centuries its successors have opened up the whole of mathematical physics: heat,
light, sound, fluid mechanics, and later relativity and quantum theory.
Mathematical thinking has become the central paradigm of the physical sciences.
Until very recently, the life sciences were different. There, mathematics was
at best a servant. It was used to perform routine calculations and to test the
significance of statistical patterns in data. It didn’t contribute much conceptual
insight or understanding. It didn’t inspire great theories or great experiments.
Most of the time, it might as well not have existed.
Today, this picture is changing. Modern discoveries in biology have opened
up a host of important questions, and many of them are unlikely to be answered
without significant mathematical input. The variety of mathematical ideas now
being used in the life sciences is enormous, and the demands of biology are
stimulating the creation of entirely new mathematics, specifically aimed at living
processes. Today’s mathematicians and biologists are working together on some
of the most difficult scientific problems that the human race has ever tackled –
including the nature and origin of life itself.
Biology will be the great mathematical frontier of the twenty-first century.
Mathematics of Life celebrates the rich variety of connections between
mathematics and biology that already exist, from the Human Genome Project,
through the structure of viruses and the organisation of the cell, to the form and
behaviour of entire organisms and their interaction in the global ecosystem. It
will also show how mathematics can shed new light on difficult issues
concerning evolution, where many important processes take too long to observe,
or happened hundreds of millions of years ago and have left only cryptic traces.
Initially, biology was about plants and animals. Then it was about cells. Now
it is mostly about complex molecules. To reflect these changes in scientific
it is mostly about complex molecules. To reflect these changes in scientific
thinking about the enigma of life, the book starts from the everyday human level,
and follows the historical path that led biologists to focus ever more sharply on
the microscopic structure of living creatures, culminating in DNA, the ‘molecule
of life’.
Most of the material discussed in the first third of the book is therefore about
biology. However, mathematics makes an early appearance, tracing questions
about the geometry of plants from Victorian times to the present day, to illustrate
how new mathematical ideas have been motivated by biology. Once the
biological background has been established, mathematics comes to centre stage
as we build up from the atomic scale, back to the level with which we feel most
comfortable, the one on which we all live. The world of grass, trees, sheep,
cows, cats, dogs ... and people.
The mathematics involved is far-ranging: probability, dynamics, chaos
theory, symmetry, networks, mechanics, elasticity – even knot theory. Most of
the applications discussed here are to mainstream mathematical biology: the
structure and function of the complex molecules that co-ordinate the complex
processes of life, the shapes of viruses, the evolutionary games that led to the
huge diversity of life on this planet and are still happening today, the workings
of the nervous system and the brain, the dynamics of ecosystems. I’ve also
included chapters on the nature of life and the possible existence of alien life
forms.
The interaction between mathematics and biology is one of the hottest areas
of science. It has already come a long way in a very short time. Only the future
will show just how far it can go. But one thing I guarantee: it’s going to be an
exciting ride.
Ian Stewart Coventry, September 2010