Collected Papers of Michael E. Soulé: Early Years in Modern Conservation Biology

By Michael E. Soulé

In the early 1970s, the environmental movement was underway. Overpopulation was recognized as a threat to human well-being, and scientists like Michael Soulé believed there was a connection between anthropogenic pressures on natural resources and the loss of the planet’s biodiversity. Soulé—thinker, philosopher, teacher, mentor, and scientist—recognized the importance of a healthy natural world and with other leaders of the day pushed for a new interdisciplinary approach to preserving biological diversity. Thirty years later, Soulé is hailed by many as the single most important force in the development of the modern science of conservation biology.

This book is a select collection of seminal writings by Michael Soulé over a thirty-year time-span from 1980 through the present day. Previously published in books and leading journals, these carefully selected pieces show the progression of his intellectual thinking on topics such as genetics, ecology, evolutionary biology, and extinctions, and how the history and substance of the field of conservation biology evolved over time. It opens with an in-depth introduction by marine conservation biologist James Estes, a long-time colleague of Soulé’s, who explains why Soulé’s special combination of science and leadership was the catalyst for bringing about the modern era of conservation biology. Estes offers a thoughtful commentary on the challenges that lie ahead for the young discipline in the face of climate change, increasing species extinctions, and impassioned debate within the conservation community itself over the best path forward.

Intended for a new generation of students, this book offers a fresh presentation of goals of conservation biology, and inspiration and guidance for the global biodiversity crises facing us today. Readers will come away with an understanding of the science, passion, idealism, and sense of urgency that drove early founders of conservation biology like Michael Soulé.

• Language: English
• Publisher: Island Press
• Release date: Oct 21, 2014
• ISBN: 9781610915762

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COLLECTED PAPERS OF MICHAEL E. SOULÉ

Collected Papers of Michael E. Soulé

EARLY YEARS IN MODERN CONSERVATION BIOLOGY

by Michael E. Soulé

with Robert L. Peters

Copyright © 2014 Michael E. Soulé

All rights reserved under International and Pan-American Copyright Conventions. No part of this book may be reproduced in any form or by any means without permission in writing from the publisher: Island Press, 2000 M Street, Suite 650, Washington, DC 20036

Island Press is a trademark of The Center for Resource Economics.

A list of permissions and original sources appears on pages 351–355.

Library of Congress Control Number: 2014949965

Printed on recycled, acid-free paper

Manufactured in the United States of America

10 9 8 7 6 5 4 3 2 1

Keywords: Island Press, conservation biology, ecology, biodiversity, biological diversity, global biological diversity, Soule, Michael Soulé, Michael E. Soulé, interdisciplinary approach, wildlife management, Society for Conservation Biology, Ecological Society of America, The Wildlife Society, biodiversity crisis, intrinsic value, global extinction crisis, conservation genetics, ecologically effective populations, Wildlands Project, Wildlands Network, Spine of the Continent, keystone species, large carnivores, genetic diversity, large landscape conservation, continental conservation, trophic cascades, highly interactive species, connectivity, landscape permeability

CONTENTS

Note from the Publisher

Preface

Introduction

James A. Estes

1Conservation Biology: Its Scope and Its Challenge

Michael E. Soulé and Bruce A. Wilcox

2What Is Conservation Biology?

Michael E. Soulé

3The Millennium Ark: How Long a Voyage, How Many Staterooms, How Many Passengers?

Michael Soulé, Michael Gilpin, William Conway, and Tom Foose

4Conservation Biology and the Real World

Michael E. Soulé

5Reconstructed Dynamics of Rapid Extinctions of Chaparral-Requiring Birds in Urban Habitat Islands

Michael E. Soulé, Douglas T. Bolger, Allison C. Alberts, Raymond Sauvajot, John Wright, Marina Sorice, Scott Hill

6The Onslaught of Alien Species, and Other Challenges in the Coming Decades

Michael E. Soulé

7Conservation: Tactics for a Constant Crisis

Michael E. Soulé

8Conservation Genetics and Conservation Biology: A Troubled Marriage

Michael E. Soulé and L. Scott Mills

9The Social and Public Health Implications of Global Warming and the Onslaught of Alien Species

M. E. Soulé, PhD

10Rewilding and Biodiversity: Complementary Goals for Continental Conservation

Michael Soulé and Reed Noss

11Conserving Nature at Regional and Continental Scales: A Scientific Program for North America

Michael E. Soulé and John Terborgh

12Ecological Effectiveness: Conservation Goals for Interactive Species

Michael E. Soulé, James A. Estes, Joel Berger, and Carlos Martinez Del Rio

13Strongly Interacting Species: Conservation Policy, Management, and Ethics

Michael E. Soulé, James A. Estes, Brian Miller, and Douglas L. Honnold

14Editorial, The New Conservation

Michael Soulé

Permissions and Original Sources

NOTE FROM THE PUBLISHER

This volume is a collection of previously published seminal papers written by Michael E. Soulé and his coauthors documenting the birth and development of the modern science of conservation biology over the past thirty years. Dr. Soulé, in collaboration with Robert L. Peters, has written a new introduction to each paper that places it in the context of the time and circumstances under which it was written and its importance to the field.

We have chosen to set the papers, which range from journal articles to book chapters, in a consistent format and typeface. We have corrected some typographical and minor errors but have otherwise retained the text, style, documentation, and idiosyncrasies of the originals. We have also removed abstracts and metadata and other associated information provided by the original publishers and have re-created figures based on the originals. Full publishing information for each paper can be found in the Permissions and Original Sources section in the back matter.

PREFACE

Conservation is not a new idea. The first Buddhist king of India, Ashoka, issued the famous Edicts of Ashoka, inscribed on pillars, that established a network of wildlife preserves around 300 BCE. The inscriptions on some of these stone monuments urged tolerance and protection of wildlife, consistent with the moral precepts of Buddhism. The belief that nature (Creation) is inherently good was also enshrined in the slightly older Jewish Pentateuch. The composition of the Pentateuch is thought to have consolidated about 500 BCE.

Notwithstanding the Pentateuch’s admonition that Creation is good, Western civilization’s commitment to this warning has been dwindling for centuries. Sadly, in recent times science itself has emerged as a potent agent in humanity’s global conquest. The biological sciences have turned back on biology, so that the fields of agriculture, medicine, and biotechnology now multiply the effects of the population explosion, probably the major driver of biodiversity loss. And corporations continue to commodify the commons—the water and air—with a perspective symbolized by the anthropocentric term natural resources.

To be fair, however, blame for nature’s diminution is more subtle and dispersed. The roots of the biodiversity crisis go deeper than science and industry, deeper than capitalism and Wall Street. This is because our hypersocial, competitive, primate nature insists that we, the people, struggle for status, stuff, and stunning mates, impelling most of us to compete in virtually all social contexts. As the lyrics from As Time Goes By in the classic film Casablanca insist: It’s still the same old story / The fight for love and glory / A case of do or die.

My personal fight for glory was subsidized by a Guggenheim Fellowship that enabled my family to live in Australia while I was on sabbatical leave (1973–1974) from the University of California, San Diego. Shortly after settling into my office in the Animal Genetics laboratory of the Commonwealth Scientific and Industrial Research Organization just north of Sydney, I got a phone call from Otto Frankel, a renowned wheat geneticist and transplanted Austrian. Frankel was interested in the protection of traditional crop cultivars. He had read my research publications on the diversification and variability of side-blotched lizards on islands in the Gulf of California and believed that the findings might be relevant to genetical conservation.

Frankel, who died in 1998 at the age of 98, wanted to discuss my conclusion that the morphological variability in island populations was correlated with the size of the island, a surrogate for population size. By then I was starting to employ starch-gel electrophoresis of proteins to see if the same relationship held at the level of genetics. Indeed, the larger the island the more the genetic variation (heterozygosity) existed in that island’s side-blotched lizards. This was the first time such a relationship had been demonstrated in nature.

I believed the genetic-phenetic correlation was salient evolutionarily because the amount of genetic variation in a population can limit how fast that population can adapt by natural selection to changing environments. This relationship is now more relevant than ever because rapid climate change and poleward-shifting habitats will severely test the adaptability of many species, particularly in fragmented landscapes. From this century on, the law for survival will be migrate, evolve, or perish.

What to do? In 1985, some colleagues and I formed the Society for Conservation Biology because we felt compelled to respond to the unprecedented scale and rate of human assaults on nature that had begun to be documented in the 1960s. We thought then, and I still believe, that the reduction of biological diversity of the planet is the most catastrophic issue of our era. Moreover, as scholars, agency biologists, and zoo curators and officials, we believed that our knowledge might help in the fight to protect nature. Some of us also believed that genetics was being ignored by institutions such as zoos and that conservation genetics was one of several new approaches that must be foundational elements in this new discipline.

In the thirty-some years since the Society’s founding, conservation biologists have grown in number and influence. Many colleges and universities initiated majors and graduate programs in conservation biology. Membership in the Society for Conservation Biology exploded, reaching a peak of 10,000 before relaxing back to a more humble magnitude. Of course, a large tally of experts in project or field is not a sign of success. As Aldo Leopold wrote in part 3 of A Sand County Almanac:

In 1909, when I first saw the West, there were grizzlies in every major mountain mass, but you could travel for months without meeting a conservation officer. Today there is some kind of conservation officer behind every bush, yet as wildlife bureaus grow, our most magnificent mammal retreats steadily toward the Canadian border. (A Sand County Almanac: And Sketches Here and There, 1966, p. 198.)

Nevertheless, we can mark some important accomplishments. Conservation biologists helped (and still help) to create many new protected areas in the developing world, and we have been instrumental in pulling some species, like the California condor and the black-footed ferret, back from the brink of extinction.

This rather personal book is a kind of history of one biologist’s collaborative effort to combine scholarship and activism in the service of nature. It is also a personal history of the origin and development of conservation biology. I hope that it will encourage those at the beginning of their careers and those already established to ask themselves if their lives and works have helped the others that cannot speak or write but whose eloquence is projected in their grace, their beauty, and their determination to live and reproduce.

Also, I hope it will inspire younger biologists and citizen scientists to receive and pass on the lamp of compassion for the wild and carry it to the myriad places and communities in need of more light.

Is there a future for the world of creatures, the survivors of the Pleistocene? I say in one of my essays that I believe in possibilism. By this I mean that I am neither a pessimist nor an optimist, but that I believe that it is still possible to save diverse and beautiful creatures and self-willed places and for the dominant species to awaken to the intrinsic value of biological diversity.

Another way to express my feelings is this: Conservation Is Another Way to Love. I believe that conservationists are lovers of the wild, the untrammeled, motorless, self-willed, life-filled places, those remote and even those in the vacant lot down the street.

ACKNOWLEDGMENTS

This book has been a team effort. Rob Peters, a founder and pioneer in the climate change arena and a lead scientist with Defenders of Wildlife, wrote the first drafts of the paragraphs that introduce each of the papers in this book. I am forever in his debt.

My dear friend Jim Estes, recently elected to the National Academy of Sciences, graciously wrote the introduction to this volume. No one is more courageous than Jim in the campaign to protect keystone species and processes that maintain the biological diversity of Earth’s oceans and lands. I also thank the wild, scaly, hairy predators, the large herbivores, and the terrestrial, marine, and aquatic leafy and microbial beings that ensure the stability and diversity in wilder places.

My assistant Arlyn Alderdice not only kept my office functioning throughout the development of this project but demonstrated her biological fitness (with the help of her husband) in the process, even bringing her newborn, Anduin, to coo as the manuscript was being constructed.

My partners and colleagues are too many to mention but I must thank Dave Foreman, Jim Estes, John Terborgh, Reed Noss, Joel Berger, Don Weeden, Terry Tempest Williams, John Davis, David Johns, Tom Butler, Eileen Crist, and other wily-wild warriors. I am also grateful to the other coauthors and collaborators of papers in this book, including Bruce Wilcox, Michael Gilpin, William Conway, Tom Foose, Douglas Bolger, Allison Alberts, Ray Sauvajot, John Wright, Marina Sorice, Scott Hill, Carlos Martinez Del Rios, Brian Miller, and Douglas Honnold. Singularly, this book would not exist absent Barbara Dean’s intelligent and patient tinkering.

Finally, my tireless, loving wife Joli Soulé provided constant tangible and emotional support throughout this project. Thank you, Joli.

Michael E. Soulé

Introduction

JAMES A. ESTES

Until recently, humans perceived wild nature as a vast unknown—something to be feared; something to be conquered; and something that was inexhaustible. There is nothing in our evolutionary history, and thus nothing in our genes, to make us feel and behave otherwise. Despite the popular perception of primitive peoples as wise stewards of natural resources, most early cultures probably exploited natural resources to their maximum abilities. Then as now, the rates of resource exploitation and utilization were linked to survival, power and wealth, and overall quality of life. Although such claims are difficult to demonstrate in the absence of written language, accounts of collapsed civilizations (Diamond 2005) together with a growing weight of evidence for human-caused extinctions of many large vertebrates (Martin 2007, Koch and Barnosky 2006) make me doubt that ancients lived with much in the way of a conservation ethic. The same is true for the period of exploration and discovery by modern societies. Magellan, Columbus, Cook, Bering, Lewis and Clark, and even Darwin—none of the early explorers had reason to think about, much less worry over, conservation. After all, their charge was to conquer and transform the spoils of their conquests into profits, not to conserve. Thomas Huxley’s errant advice to cod fishers in the North Atlantic—continue trawling despite the fishermen’s own concern for stock collapse (Kurlansky 1997, Roberts 2007)—captures the prevailing view of nature and natural resources as well as any. The notion of conservation, defined as the measures needed to provide for a sustainable future, was simply not part of our early lexicon.

This all began to change as human numbers marched steadily upward. Recognition of nature’s limits in the face of growing populations can be traced back at least to the eighteenth century writings of Thomas Malthus. This principle of population biology—the notion of environmental carrying capacity—was formalized in the logistic growth equation [dN/dt = rN(1 – N/K), where N = population size, r = the intrinsic rate of population increase, and K = environmental carrying capacity]. The logistic growth equation led to the famous Lotka-Volterra competition equations (a simple expansion of the logistic in which two species are limited by a common resource) and subsequently to the first serious efforts to conserve and manage exploited populations of wild plants and animals. Beverton and Holt’s (1957) treatise on the biology of exploited populations is a famous example directed primarily at fisheries management. Earth scientists recognized and had become concerned about the finite nature of geological resources even earlier, as evidenced by warnings from such well known people as John Wesley Powell, founding director of the US Geological Survey. Awareness of the need for conservation continued to build into the early twentieth century, no doubt influencing the landmark policies of Teddy Roosevelt’s administration.

My point is that a human recognition of the need to conserve natural resources, while thought of by many as something quite recent, in fact has been around for a while. But like most creative human endeavors, the growth of the conservation movement seems to be characterized by long periods of stasis followed by short periods of rapid change. These periods of rapid change are often pushed forward by men and women with two special qualities—the vision to see what is needed and the charisma and strength of character to draw others along with them. Through the first half of the twentieth century, people like John Muir, Rachel Carson, and Aldo Leopold indelibly influenced the pathway of conservation. History will no doubt add Michael Soulé to this list of influential conservationists.

The impacts of leaders in the conservation movement commonly arise through philosophical transformations that occur during their own lives. Aldo Leopold, arguably the most revered figure in the history of conservation, was a game manager by training who began his career with the US Forest Service during the era of predator control. Early in his professional life, he sought to enhance wildlife by regulating human exploitation while at the same time minimizing losses to predators. Later he came to realize the shortcomings of his early beliefs, embracing a more holistic view of ecology, management, and environmental ethics that was articulated in the poignant prose of his enduring classic, A Sand County Almanac (Leopold 1949).

Despite messages for conservation by the movement’s early visionaries, natural resource conservation turned in a different direction through the middle decades of the twentieth century—toward the objective of a maximum sustainable yield. A maximum sustainable yield is the ideal of taking as many as possible from an exploited population, while at the same time not so many as to cause that population to collapse. This ideal became the mantra of natural resource management, surfacing as the integrating principle in our efforts to conserve the three main elements of wild living nature—fish, wildlife, and forests. Programs in wildlife biology, fisheries science, and forestry emerged to conduct research and train the next generation of practitioners on how to achieve sustainable yields.

The practices and beliefs that grew out of wildlife, fisheries, and forestry science did not encompass much of what would eventually become conservation biology. Movement in that direction lay largely dormant from the time of Leopold’s death in 1948 through the 1960s. Even today, conservation and management conjure up different images, at least in my mind. Management, as I think of it, involves the manipulation of species and habitats for direct and immediate human benefit, whereas the chief goal of conservation is the maintenance of biodiversity. A tension between these views and philosophies can be seen almost everywhere as modern-day natural resource managers and conservationists struggle to define a way forward. Through the mid decades of the twentieth century, the key disciplinary elements of what would eventually coalesce into what was first called Conservation Biology and has more recently been termed Conservation Science—ecology, natural resource management, genetics, economics, and environmental ethics—developed mostly in isolation of one another.

As human populations have continued to grow, as technologies have continued to develop, and as the economic imperative of an increasingly democratic global society has ever more strongly pressed natural resources to fuel this imperative, limits to growth and the sustainable use of natural resources inevitably have resurfaced as questions of increasing concern. No rational modern person could deny the fundamental truth in this vision of our planet’s future. But the devil is in the details. Just what are the limits to growth, and as we continue to proceed along that path how can we preserve the rest of the natural world for our own future and the generations to come? These are the questions that a small number of biologists, economists, philosophers, and others began asking again in earnest a few decades ago. The result was the birth of modern conservation biology. Michael Soulé had a strong hand in that endeavor and as a result is sometimes referred to as the father of conservation biology.

I was deeply honored when Barbara Dean asked me to write an introduction to the volume. But after agreeing to do this, I faced the question of what to say. I decided to begin with a retrospection—admittedly my own view—of how and why conservation biology came to be. I’ve done that, briefly and superficially, in the proceeding pages. My focus from here forward will be on Michael Soulé—his history, especially during the period of our acquaintance; his contribution to conservation biology as we know it today; and his sundry influences on the infrastructure of conservation. I’ll end with a look to the future, considering in particular the recently emerged and charged debate over what conservation science is and should become going forward.

Michael grew up in southern California where as a child he fell in love with nature by roaming the area’s then undeveloped chaparral canyons. After graduating from high school, he attended San Diego State University as an undergraduate and Stanford University as a graduate student. He studied with Paul Ehrlich at Stanford, whose concerns over human population growth and its resulting environmental effects profoundly influenced Michael’s own intellectual development. By this point his career path was established.

Upon completing his doctorate, Michael took a faculty position in the Biology Department at the University of California at San Diego. But his life in San Diego was filled with turmoil as he watched the wild canyons of his childhood succumb to development. Just a few years later he resigned his faculty post at UCSD and moved to a Buddhist commune in Los Angeles where he sought a new peace and understanding. That experience was transformative to his perceptions of self and human behavior. But Michael’s love of nature and his desire to help protect it were unfulfilled, and so he left the confines of spiritual study and returned to academia, this time with the Department of Natural Resources at the University of Michigan. Michael emerged as a leader in the developing science of conservation biology during his years at Michigan, helping found the Society for Conservation Biology, serving as the Society’s first president, and writing several influential books on the then nascent science of conservation biology. Michael left Michigan in 1989 to revitalize the then foundering Environmental Studies program at the University of California at Santa Cruz. He retired from UCSC in 1996 and moved to southwestern Colorado where he has continued to pursue the fulfillment of his vision for the needs of conservation.

I had first learned of Michael Soulé in the early 1970s during a visit to San Diego, my home town. I was still a graduate student at the time. My mother, who was not a scientist or even an amateur naturalist, was appalled by the unregulated and rampant development of San Diego County. She had heard Michael speak about the perils of human population increase, was influenced by the force of his logic and personality, and asked me if I knew of him. I didn’t at the time, but I later would as interest in conservation biology literally exploded and Michael assumed a leading role in that movement during the late 1970s and 1980s. We met briefly in 1988 in Davis during SCB’s first symposium on marine conservation. He struck me then as a man of substance and purpose. We met again when he interviewed for the directorship of Environmental Studies at UCSC. Michael was offered and accepted the job, moved to Santa Cruz later in 1989, and soon thereafter we became professional associates and close personal friends.

I worked with Michael during the first year of the Clinton administration in an unsuccessful attempt to convince the newly created National Biological Survey to locate their California field station at UC Santa Cruz. Michael argued that Santa Cruz would both provide the best intellectual infrastructure for moving the young agency into the arena of conservation biology and serve as a genuine academic collaborator. He tried to convince the powers that were in the Department of the Interior that UCSC and their newly formed agency shared a common ideal and UCSC therefore would provide more than just a place to be. But in the end we lost out to UC Davis, ostensibly because of their higher prestige in ecology and close proximity to Sacramento. The Davis connection eventually collapsed and the California Science Center moved to Sacramento State University, where it presently resides.

Although my endeavor to help Michael build a viable program in conservation biology at UC Santa Cruz never amounted to much, our friendship did. In thinking back over my life as a naturalist, an ecologist, and a conservation biologist, Michael was one of three people who most strongly influenced my own path. The first of these people was my uncle, Frank Springer, a small town physician in western Wisconsin who over the course of my childhood instilled in me a spirit of romance and adventure, and later convinced me to study biology. The second was the eminent ecologist Robert T. Paine, who opened my eyes to the wonders of ecology and taught me how to learn about these things. And the third was Michael, who helped me define my soul. He did this over the course of our many conversations through his intellect, his openness, his honesty, his charisma, and his depth of understanding of so many things.

The same qualities that drew me to Michael Soulé as a friend and respected colleague also led him to become the single most important force in the development of modern conservation biology. This influence arose further from the interplay of his science and his leadership. There are many strong leaders and there are many excellent scientists. But very few people do both well. Michael is one of those few.

Michael’s leadership has come in various ways, some of which are obvious and others less so. He built the very foundations of modern conservation biology by helping to establish the Society for Conservation Biology and then serving as the Society’s founding president. He led the development of the Environmental Studies Program at UC Santa Cruz by establishing and then putting in place a vision for research and training in conservation biology, one I might add that emphasized an integration of the natural and social sciences. As Chair of Environmental Studies, he convinced the university to embrace this vision and then cajoled them into providing the human, physical, and financial resources required to move it forward. From the outset Michael recognized the multidimensional and multidisciplinary aspects of what conservation biology needed to be, and with that view in mind he repopulated the Environmental Studies faculty with a cohort of bright new junior faculty from the natural and social sciences. The downside of doing this was living with the often fundamentally different approaches, standards, and philosophies of academics in the natural and social sciences. Then as now, the disagreements were over the needs of people versus the welfare of nature. Michael pressed his agenda forward through all this, not always with a gentle hand. At the same time he mentored a number of graduate students and junior faculty who themselves have gone on to become leaders in the next generation of conservation biologists.

Michael has helped lead the science of conservation biology in two main ways—through his hands-on research, some of which was done in collaboration with students and other colleagues; and through the organization of workshops and symposia designed to address key issues in the emerging science of conservation biology. The papers reprinted in this anthology are a sampling of Michael’s essays, reviews, and empirical studies from the peer-reviewed literature and from the various books he organized, wrote or helped write, and published or co-published.

Looking back across Michael’s body of scientific work, it is possible to identify three main dimensions that define his view of conservation biology. The first of these is population viability. Biodiversity conservation is and always has been Michael’s most deeply rooted objective. In its simplest form, the conservation of biodiversity is akin to preventing extinction. And for species to avoid becoming extinct, they must persist as viable populations. This simple idea underpins much of what Michael has to say in the first four papers. In particular, the fourth, Conservation Biology and the ‘Real World,’ is a classic that asks the question, how many species and how many individuals of each species must we humans prevent from going under through the extinction crisis? A more detailed series of analyses and discussions are available in Michael’s edited volume on the subject (Soulé 1987). The appeal of a population viability analysis is almost visceral because it specifies, for any desired range of future scenarios, the probabilities of and/or expected times to extinction. These questions and approaches, pioneered by Michael and his colleagues, resonated with natural resource managers and applied ecologists, as evidenced by the subsequent explosion of methods and analyses. How to books have since been written, detailing what are often highly quantitative methods and even providing the code necessary for their specific application. Virtually every new or revised recovery plan for a threatened and endangered species under the US Endangered Species Act includes some sort of population viability analysis. Often these analyses define the most scientifically objective and substantive part of the recovery planning process.

A second dimension in the Soulé science legacy is conservation genetics. Michael’s training and basic scientific interests revolved strongly around evolutionary biology. His early work on island-lizards in the Gulf of California focused on isolation, adaptation, and speciation, which among other things led to major contributions in the study of bilateral asymmetry (Soulé 1967, 1982). From the outset of his life as a naturalist, he has understood that populations are not simple collections of similar individuals but instead that those individuals vary to one degree or another in their genetic makeup. Michael understood further that this genetic variation is an essential part of biodiversity because it counters the deleterious effects of inbreeding, allows populations to adapt to diverse and varying environments, and provides the substrate for future evolutionary change in an ever-changing world. Michael’s voice on recovery teams (outside experts appointed by the responsible federal agency [usually the US Fish and