Improbable Planet: How Earth Became Humanity's Home
By Hugh Ross
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About this ebook
Most of us remember the basics from science classes about how Earth came to be the only known planet that sustains complex life. But what most people don't know is that the more thoroughly researchers investigate the history of our planet, the more astonishing the story of our existence becomes. The number and complexity of the astronomical, geological, chemical, and biological features recognized as essential to human existence have expanded explosively within the past decade. An understanding of what is required to make possible a large human population and advanced civilizations has raised profound questions about life, our purpose, and our destiny. Are we really just the result of innumerable coincidences? Or is there a more reasonable explanation?
This fascinating book helps nonscientists understand the countless miracles that undergird the exquisitely fine-tuned planet we call home--as if Someone had us in mind all along.
Hugh Ross
Hugh Ross (PhD, University of Toronto) is founder and president of Reasons to Believe (www.reasons.org). He is the author of many books, including More Than a Theory, Why the Universe Is the Way It Is, and Improbable Planet. An astronomer, Ross has addressed students and faculty on over three hundred campuses in the United States and abroad on a wide variety of science-faith topics. From science conferences to churches to government labs, Ross presents powerful evidence for a purpose-filled universe. He lives in the Los Angeles area.
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Improbable Planet - Hugh Ross
© 2016 by Reasons to Believe
Published by Baker Books
a division of Baker Publishing Group
P.O. Box 6287, Grand Rapids, MI 49516-6287
www.bakerbooks.com
Ebook edition created 2016
Ebook corrections 07.13.2017, 02.04.2022
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means—for example, electronic, photocopy, recording—without the prior written permission of the publisher. The only exception is brief quotations in printed reviews.
Library of Congress Cataloging-in-Publication Data is on file at the Library of Congress, Washington, DC.
ISBN 978-1-4934-0539-8
Scripture quotations are from the Holy Bible, New International Version®. NIV®. Copyright © 1973, 1978, 1984, 2011 by Biblica, Inc.™ Used by permission of Zondervan. All rights reserved worldwide. www.zondervan.com
"In Improbable Planet, Ross holds readers’ hands, leading them in a readable yet gently technical format through a compelling layer-upon-layer argument for the distinctiveness of the planet on which we live and of the preparation for inimitable life on Earth. The text is replete with references from primary scientific articles in some of the most well-respected journals, underscoring the highest academic rigor taken in substantiating the factual claims. Only the shamefully flippant could dismiss this book as being a faith-filled presentation rather than the scholarly work it represents."
James M. Tour, T. T. and W. F. Chao Professor of Chemistry, Rice University; R&D magazine’s 2013 Scientist of the Year
"This book, Improbable Planet, brings forth from the reader a triumphant shout of thanksgiving to a God who is the Author of our creation. In the process, Hugh Ross brilliantly silences those who would claim that this Earth, this solar system, this galaxy, and this universe are nothing but a mere accident. Improbable Planet is technical yet poetic; thoroughly scientific yet faith-inspiring. I commend it to anyone who seriously contemplates the wonder of this planet we call Earth."
Pat Robertson, founder/chairman, The Christian Broadcasting Network, Inc.
Hugh Ross takes us on a riveting tour of the scientific story, from the beginning of the cosmos to present humankind. He shows, from the perspective of cosmology, planetary science, geology, ecology, and biology, how that story pushes us toward the conclusion that purpose has driven the whole story, with the different pieces intertwined and each supporting the production of an ideal habitat for human beings right here and right now. But that isn’t the final goal of the story: rather, we were brought here to live eternally with our Maker. Not only will this commend Christian faith to scientifically minded inquirers, but it will also strengthen the confidence of believers that we inhabit and participate in a meaningful and purposeful story.
C. John Jack
Collins, professor of Old Testament, Covenant Theological Seminary
"Improbable Planet provides sound biblical and scientific support for a Creator. With thorough notations and research, Dr. Hugh Ross takes us on a journey through time and space to bring us firmly back to our own planet, formed by one Creator. For those who need a scientific explanation of our universe and the life-forms within it, you will be satisfied. For those who already believe that God’s divine hand created the world and all life within, you will be validated. Hugh Ross writes to stretch our intellect and to strengthen our faith. Improbable Planet does the improbable—demonstrates that the language of science does not threaten but instead augments the prose of evangelism."
Ed Young, senior pastor, Second Baptist Church, Houston, TX
"Hugh Ross is a gift. He belongs to that rarefied and exceedingly small group of people who combine brilliance of mind, an originality of thought that rivals the most creative thinkers, and an encyclopedic knowledge of both the Bible and science. Improbable Planet is the latest expression of these traits. You do not need to know either science or the Bible to understand the book, but the more you know about either, the more impressive you will find the achievement. Anyone would immensely benefit from reading Improbable Planet."
Dennis Prager, nationally syndicated radio talk show host and columnist, New York Times bestselling author, and founder of PragerUniversity.com
When topics like intelligent design and fine-tuning are being explained, Hugh Ross is one of the beloved and most widely read scientific authors. Adding to Ross’s reputation, this book will not disappoint readers. Whether the topic is the mass of the universe, the Milky Way Galaxy, the failures of abiogenesis, or the Cambrian explosion, much of this text reads like the explanations behind the gorgeous photos of space that we often witness. I predict a wide audience!
Gary R. Habermas, Distinguished Research Professor of Apologetics and Philosophy, Liberty University
"Dr. Ross has done it again! With his typical clarity, insight, and precision, Ross shows how recent scientific findings undermine naturalism while simultaneously providing evidence that there is a plan, purpose, and design in the universe. Whether you are a skeptic or a believer, you will be challenged and equipped immensely by reading Improbable Planet. I highly recommend it."
Sean McDowell, PhD, professor, Biola University; bestselling author of over 15 books, including A New Kind of Apologist
"In Improbable Planet, Hugh Ross presents the most detailed analysis yet of the Goldilocks ‘just right’ circumstances that make Earth home to all of its inhabitants. The book builds an enthralling tale of the conditions that allow and promote life to exist and thrive here."
Gerald B. Cleaver, professor and head, Early Universe Cosmology and Strings Division, Baylor University
"Improbable Planet is a remarkably researched and detailed account of the geological, chemical, and biological history of Earth. Readers will encounter a fascinating and informative book, even apart from any theological or philosophical implications. An unimaginable series of finely timed and tuned events were required in order for the primordial Earth to develop into a planet capable of supporting higher life forms and allowing an advanced civilization to thrive. The improbability of our planet becoming the paradise that it is provides strong evidence that there is a divine plan and providential design behind it all and that humans and our planetary home have a deep significance in the universe."
Michael G. Strauss, David Ross Boyd Professor, University of Oklahoma
As one who has spoken to millions of despairing atheists in Russia and Ukraine, I am persuaded that the case for the Creator as proposed by Ross is well nigh irrefutable. Hugh’s observation that we find ourselves in a collection of 200 billion stars, in a universe of some 200 billion galaxies, in just the right place, at just the right time, and with just the right view, makes one think that perhaps Someone designed it all. Here is a fact-filled book that will stir the debate about origins while intellectually challenging popular atheistic concepts.
John Carter, president, The Carter Report, Moorpark, CA
"Hugh Ross’s proven scientific credentials and his enduring commitment to biblical Christianity qualify him to speak authoritatively in the often raucous encounter between science and theology. The quality of Hugh Ross’s work in Improbable Planet is characterized in his stated efforts to respond to Carl Sagan’s assertion that ‘the cosmos is all there is or ever was or ever will be.’ Using scientific evidence, Ross skillfully validates the biblical affirmation that this universe serves as a launching pad for the new creation to come. He powerfully reveals the deep biblical foundations that undergird his extensive scientific explanations, offering a model of thoroughness that should characterize biblical Christianity’s interface with science."
Byron D. Klaus, former president, Assemblies of God Theological Seminary
Contents
Cover
Title Page
Copyright Page
Endorsements
Acknowledgments
1. Why Ask Why
?
2. The Way the World Is
3. Essential Construction Materials
4. The Right Neighborhood
5. Site Preparations
6. Not Quite Ready
7. Ready for the Foundation
8. Construction Begins below Ground
9. Up to Ground Level
10. Air-Conditioning
11. Invisible Progress
12. Heating and Ventilation
13. The Structure Rises
14. Finishing Touches
15. Ready for Occupancy
16. Why We’re Here
Appendix A: Why Not Life on a Moon?
Appendix B: Are We Alone in the Universe?
Notes
Index
About the Author
Back Ads
Back Cover
Acknowledgments
During the five years I spent reviewing the literature and organizing my thoughts for this book, my Sunday morning Paradoxes class became my sounding board. The class members’ questions, challenges, and critiques played a significant role in shaping the content. So thanks to everyone who patiently and persistently participated in those interactions.
The next person to help me organize my thoughts, arrange them into chapters, and put them into words was my partner in life and ministry, Kathy. As usual, she protected my writing time, encouraged me to keep going, and then took the lead in editing the manuscript. She faced the nearly impossible job of balancing my demand for scientific accuracy with the readers’ desire for accessibility. Thanks, Kathy, for never giving up on this task—or on me.
After this initial work, five more editors who are part of my team at Reasons to Believe stepped up to help. Special thanks to Joe Aguirre, Sandra Dimas, Linda Kloth, Maureen Moser, and Amanda Warner for checking and rechecking all the citations and quotations in the book, helping me work in the revisions and additions suggested by early reviewers, performing detailed copyedits, and preparing the index. The many hours you invested made an enormous difference in the quality of this work. I cannot thank you enough.
As these editors continued their labor, a stellar group of scholars including and in addition to my colleagues at RTB took time to review the science and offer their recommendations. I’m especially grateful to astronomer Kyle Cudworth, biochemist Russ Carlson, and geologists Ken Wolgemuth and Steve Keyes. Your many helpful suggestions and revisions improved the book’s content without exceeding reasonable limitations on word count.
Others who deserve special mention and appreciation include my assistant, Diana Carrée, and the members of RTB’s advancement and ministry care teams. Your support, encouragement, and extra effort allowed Kathy and me to focus intensely for weeks on writing and editing. Time and again your service goes far beyond the call of duty. I’m blessed to work with men and women who share my passion for providing new reasons to believe in Jesus Christ, our Creator and Savior.
Finally, let me go back to where this writing project began—in conversations with my agent, Steve Laube, and Baker Publishing Group’s executive editor Bob Hosack. What started as a discussion of the fossil record grew much deeper and wider as we went along. Thank you for allowing me to expand the scope of the project I had initially proposed. Your enthusiasm has been, and remains, invaluable.
1
Why Ask Why
?
A few years ago I wrote a book called Why the Universe Is the Way It Is to show what the characteristics of the universe—its age, mass, dimensions, physical laws, and other physical features—tell us about humanity’s ultimate purpose and destiny.[1] I wrote it also as an appeal to those who reject the Creator on the basis that they, as mere humans, can conceive of a better universe than ours to reconsider their claim in light of new discoveries. My aim in that book was to demonstrate how our seemingly imperfect
universe fits perfectly with what I describe as a two-creation model of reality. Rather than upholding Carl Sagan’s assertion that the cosmos is all that is or ever was or ever will be,
[2] evidence supports the biblical assertion that this universe serves as a launchpad for the new creation to come—a reality more perfect than any of us can think of or imagine, one that fulfills all our greatest hopes and deepest longings.
In many respects the book in your hands is a sequel to that book—a necessary sequel, given popular notions about Earth as a not-so-special, often hostile, and, in a worst-case scenario, possibly replaceable home for humanity. Of all the things in life we tend to take for granted, our terrestrial residence and its resources might be one of the biggest. We don’t seem to be amazed and astonished by Earth’s beauty and treasures, its capacity to support more than 7 billion people and even more billions of other creatures.
Most people I meet, including scientists, acknowledge that Earth has undergone some changes since it first coalesced from the disk of gas and dust surrounding our star, the Sun, but few can even imagine how radically different it is today. Many suggest that Earth’s life-sustaining features are just amazing coincidences
that somehow fell into place in a way that suits human needs and, at the same time, determines what life-forms exist.
Evidence and logic compel me to challenge such a notion. Ongoing research tells us that Earth has been shaped not only by an intricately orchestrated interplay of physical forces and conditions, but also by its vast abundance and diversity of life-forms. By means that no depth and breadth of scientific research can explain, life arose early in Earth’s history under anything but the benign conditions it would seem to require and somehow persisted through multiple mass extinction events, always appearing or reappearing at just-right times and in just-right forms to meet the needs and demands of the revised environment.
The more thoroughly researchers investigate the history of our planet, the more astonishing the story of our existence becomes. The number and complexity of the astronomical, geological, chemical, and biological features recognized as essential to human existence have expanded explosively within the past decade. The importance of this new information cannot be overstated. An understanding of what is required to make possible a large human population and advanced civilization has raised profound questions about life, especially about our purpose and destiny. In other words, discovering at this level of detail why the history of Earth looks the way it does impacts all discussion of why you and I are here. Are we simply the result of a colossal matrix of innumerable, narrow coincidences, against all odds, or is there a more reasonable explanation? And if the world is the handiwork of a divine Creator, why is it so full of misery and danger for so many of its inhabitants?
The reason most reviews of Earth’s history fail to arrest our attention and rivet our thoughts about humanity’s purpose and destiny may well reside in the cursory manner whereby the subject is typically addressed. We all know—or at least think we know—what Earth’s history looks like. A bunch of dust surrounding the newly formed Sun clumped together by gravity to form a seemingly random set of planets. One of those planets, the one we call Earth, was the Goldilocks planet,
a just-right place with just-right conditions and ingredients for a simple life-form to pop into existence from a conglomeration of chemicals and somehow manage to stay in existence. We learned in school that over a very long time and despite some occasional setbacks, Earth’s environment allowed for and produced progressively more diverse and complex life. We learned that this extended process eventually gave rise to human beings, endowed with the resources and capacities to launch, develop, and perhaps sustain advanced civilization.
What most of us do not know, however, is how radically Earth has changed since it first formed into a more or less solid ball. What’s more, even those at the cutting edge of research are just now gaining a glimpse at how many and what kinds of physical steps transformed that lifeless ball into our fully animated orb, our home.
One reason we don’t know is that this research and its findings are so new. Another is that the puzzle pieces that would help us bring the picture into focus come from a diversity of scientific disciplines: cosmology, astronomy, geophysics, atmospheric physics, geology, physical chemistry, biochemistry, and the whole spectrum of the biological sciences. A third reason, and perhaps the most significant of all, arises from what my friend Kenneth Samples would refer to as the zeitgeist, the spirit of the times. Through repeated misuses and abuses, scientific findings have lost much of their power to impact people’s view of reality and, thus, their thoughts about life’s biggest questions. While such questions are easy to postpone, they cannot be ignored. No matter how hard and how often we push them to the background, life has a way of propelling them to the forefront, often (but not always) in the face of life-altering and globally impactful events. So why wait? Let’s look together at the data scientists now have in hand and carefully consider what they tell us about how Earth, humanity, and civilization—and you and I—came to be. The story that emerges might just impact how you choose to live here and now.
2
The Way the World Is
We live on an amazing planet, a world like no other we know. The world that we know and enjoy is the result of a very long history of astronomical, physical, geological, chemical, and biological events. Without that long, complex history we would not have our present-day world, the world that is.
Preserved Record of the Past
Because of the way the world is, we have a fairly comprehensive record of how the planet got to be in its present state. Geological records throughout the world reveal Earth’s transition from a planet with only water on its surface to a realm where landmasses and oceans coexist. Thanks to these records, geologists possess a detailed understanding of the growth history of Earth’s islands and continental landmasses.
The Milky Way Galaxy, the Sun, the Moon, and the configuration of the solar system’s planets and asteroid and comet belts reveal how Earth obtained its unique stockpile of elements and minerals that enable Earth today to sustain such an enormous biomass and biodiversity. The fossil record, isotope records, geological layers, sediment cores, ice cores, and biodeposit (biological decay products embedded in Earth’s crust) inventories provide biologists and ecologists with a chronicle of Earth’s life.
Earth’s preserved record of past physical and biological events reveals an unanticipated synergy. While scientists expected that Earth’s physical history would play a role in determining life’s history, it was a surprise for them to recently discover that for the physical history of Earth to be the way it is, certain kinds and quantities of life must exist in just-right locations at just-right times.
The sheer abundance and diversity of life on Earth implies that a record of Earth’s past geochemistry and life has been preserved not only here but also on other solar system bodies. Asteroids, comets, and meteorites have bombarded Earth throughout its history. These collisions have resulted in over a million tons of Earth material, including the remains of embedded microorganisms, being deposited on the surfaces of the Moon, Mars, Venus, and other solar system bodies.[1]
Persistent Life
A remarkable feature of our world is the permanence of its life. Thanks to how long life has endured, global civilization is presently sustainable (as succeeding chapters in this book will show).
Fossils of Earth’s life date back to 3.47 billion years ago.[2] Carbon-13 to carbon-12 isotope ratio measurements (see ch. 8) indicate that life was present on our planet as far back as 3.83 billion years ago.[3]
Once life first appeared on Earth it persisted. While there is no geological period of life during which extinctions did not occur, and while occasional mass extinction events have wiped out more than half of all existing species, life nonetheless continued. There is no apparent time during the past 3.5 billion years when Earth became sterile.[4] How and why Earth never experienced a permanent sterilization event throughout the past 3.5 billion years forms the thesis for much of this book.
Abundance and Diversity
In spite of all the stresses and catastrophes it encountered throughout the past 3.8 billion years, life on Earth nonetheless has remained extremely, even maximally, abundant and diverse. This book will explore how and why that is. The biodeposit wealth within Earth’s crust alone testifies of the enormous past abundance of life. Similarly, the high oxygen and low carbon dioxide content in Earth’s atmosphere implies that photosynthetic activity must have proceeded with little or no interruption at virtually the maximum level the physical laws would permit. The fossil record testifies of exceedingly rapid recoveries from extinction events. Whoever or whatever is responsible for Earth’s life seems intent on keeping the planet as full of life as is physically possible.
The fossil record clearly exhibits a trend toward increasing diversity. Only recently have ecologists determined––with any degree of precision––the total number of species of life. That number is about 8.7 million eukaryotes: 6.5 million land species and 2.2 million marine species.[5] Not included are prokaryotes (bacteria and archaea), unicellular species whose cells lack a nucleus. Estimates of the number of prokaryotic species range from 100,000 to 10 million.[6]
Considering Earth’s small surface area, 8.7 million eukaryotic species is an incredibly high number. As a team of six astrobiologists asked, Of special relevance to astrobiology and central to evolutionary biology, we ask why there are so many species on Earth?
[7] Their question will be addressed in later chapters.
The fossil record is most complete for animals. It documents that animals first appeared shortly after 600 million years ago. From there until the present, the number of animal species existing per unit of time has increased. The strongest trend observed is for large-bodied animals.
Where the fossil record is less complete, paleontologists see the same trend. Whether they observe plants, fungi, lichens, eukaryotic unicellular life, or prokaryotic unicellular life, paleontologists note that species diversity increases with respect to time.
Simple to Complex
Previous to 600 million years ago it was impossible for the physical and chemical environment of Earth at that time to support animals’ existence. As later chapters will reveal, the physical and chemical conditions on Earth changed dramatically over the past 4 billion years. One of the enigmas of life’s history is that the complexity and diversity of life has continuously increased in direct response to the changing physics and chemistry of Earth’s surface, progressively permitting the existence of more complex and diverse life.
There are no time lags. The moment conditions allow for a greater complexity and diversity of life, that complexity and diversity immediately appear. Furthermore, they appear up to maximal limits permitted by the improved physical and chemical conditions. These patterns of immediacy and maximal complexity and diversity raise the why
question—a vital query this book will address.
Gradualism vs. Quantum Jumps
One defining feature of Earth’s life is its episodic history. The progression from simple to complex, low diversity to high diversity, tiny body sizes to large body sizes is neither linear nor gradual.
For the first 2.8 billion years of life’s history the only life-forms observed were either unicellular or colonies of unicellular life. Differentiated multicellular organisms did not arise until 1 billion years ago and animals not until 600 million years ago.
Charles Darwin presumed that the development and transformation of life throughout Earth’s history was gradual, smooth, and continuous.[8] However, in landmark articles published in 1972 and 1977, paleontologists Niles Eldredge and Stephen Jay Gould pointed out that the fossil record is typified by species remaining in extended stasis (little or no net evolutionary change) interrupted by quantum jumps where species disappear suddenly and then are followed quickly by sudden appearances of very different species.[9] Even before the publication of Eldredge and Gould’s papers, other paleontologists, such as George Gaylord Simpson, had noted an even more radical feature of the fossil record. It is not only at the species level where quantum jumps are observed but also at the level of families, orders, and classes of organisms (see table 2.1,
Classification of Life").[10]
Table 2.1: Classification of Life
This scientific taxonomy has its origin in Carl Linnaeus’s research. Linnaeus grouped species according to shared physical characteristics. In the twentieth century his groupings have been revised to correspond with the Darwinian assumption of common descent by natural means.
Three Creations of Life
As noted, Earth provides an enduring home for life. Because of the way Earth was and now is, it affords habitats for three radically different kinds, or categories, of life: (1) physical; (2) physical and mind-possessing; and (3) physical, mind-possessing, and spiritual.
However, proponents of the abiogenesis hypothesis challenge this perception of three distinct forms of life. Abiogenesis refers to the premise that some set of natural processes was responsible for life arising from nonliving matter and for primitive life evolving into advanced life. In other words, life differs by degree, not by kind.
This naturalistic perspective on life’s origin and history has impacted how astronomers view the anthropic principle.
The original definition of the anthropic (from anthropos—Greek for man
) principle states that humanity’s existence places severe constraints on the physical constants, structure and history of the universe, the Milky Way Galaxy, the solar system, Earth and Earth’s life. However, astronomer Marcelo Gleiser points out that what is now referred to as the anthropic principle in the astronomical research literature almost always amounts to nothing more than the preconditions for primitive life.
[11] Thus, the anthropic principle has become the prebiotic principle. It presumes that all life differs from the most primitive life only by degree and not by kind.
Primitive life, that is, unicellular bacterial life, is but the simplest form of life on Earth. There are three other general divisions (under category 1 above) of purely physical life: (1) differentiated multicellular organisms (for example, fungi); (2) plants; and (3) animals. In addition to purely physical life, Earth today sustains two kinds of life that possess distinctly nonphysical attributes.
One of these kinds is a group of animals that possesses a mind (category 2 above), a mind that is capable of experiencing and expressing emotions, exercising intellectual analysis, and making decisions in response to that analysis and the animal’s emotional state. All mind-possessing animals share in common the attribute of parents providing sacrificial care for their offspring. Animals in this category include all mammals and birds and a few of the more advanced reptilian species such as the crocodile and the alligator.
Another kind of life-form possessing nonphysical attributes (category 3 above) is the species Homo sapiens sapiens. Human beings not only possess a mind, they also are endowed with a spirit. This spiritual component enables humans to engage in philosophy and theology and to address questions of ultimate meaning and purpose not only about themselves but also of the rest of Earth’s life and the entirety of the universe.
The different kinds of purely physical life-forms and those possessing both physical and nonphysical attributes explains the observed hierarchy in Earth’s physical and biological features. Unicellular life can thrive without the existence of more complex life. However, multicellular organisms cannot exist without unicellular organisms. Multicellular life also requires a more highly fine-tuned physical environment than unicellular life. Likewise, mind-possessing life needs the support of mindless life and requires far more fine-tuned physical habitats. Spirit-possessing life cannot survive without all the other different kinds of life simultaneously thriving on Earth, and it demands an extremely fine-tuned physical environment. This hierarchy of dependence suggests a teleology—that the origins and history of life on Earth have a destiny and purpose, culminating in Homo sapiens sapiens.
In addition to generating habitats for life, another reason the world is the way it is appears to be so that all the different kinds of life can coexist at high population levels. Existence of the three distinct kinds of life—purely physical; physical and mindful; and physical, mindful, and spiritual—poses a