Anurag Agrawal on Monarchs and Milkweed

AgrawalMonarch butterflies are one of nature’s most recognizable creatures, known for their bright colors and epic annual migration from the United States and Canada to Mexico. Yet there is much more to the monarch than its distinctive presence and mythic journeying. In Monarchs and Milkweed, Anurag Agrawal presents a vivid investigation into how the monarch butterfly has evolved closely alongside the milkweed—a toxic plant named for the sticky white substance emitted when its leaves are damaged—and how this inextricable and intimate relationship has been like an arms race over the millennia, a battle of exploitation and defense between two fascinating species. Check the PUP blog each Monday for new installments in our “Monarch Monday” blog series by Anurag Agrawal.

What makes monarchs and milkweeds so special?

AA: Monarchs and milkweed are remarkable creatures, they’re on a wild ride! From the monarch’s perspective, its only food as a caterpillar is the milkweed plant. This makes them highly specialized, highly evolved, and very picky eaters indeed. They’re actually not that unique among butterflies, but they are extreme. Milkweed does everything in its power to defend itself against being eaten by monarchs. They make sandpapery leaves, toxins that can stop a human heart, and a thick poisonous goo that can glue an insect’s mouth shut. Again, although milkweed is not unique among plants, it is extreme. In what is called a coevolutionary arms race, monarchs and milkweed have been continually evolving over the eons to keep up with each other. As such, they have a lot to teach us about the way nature works, the way plants and animals interact, and about the various paths that evolution can take different species. And this is all to say nothing of the monarch’s spectacular annual migration, often over 3,000 miles flown by individual butterflies, using the sun to navigate, and having stored away milkweed’s poisons to protect themselves from being eaten by birds. Monarchs and milkweeds are royal representatives of all interacting species.

Why did you write this book?

AA: After studying monarchs and milkweed myself for over 15 years, I felt like I had a lot I wanted to share, especially with non-scientists and nature lovers. Monarchs and milkweed are such fascinating organisms, and yet so much of their beautiful biology is not widely known. I also wrote the book because there are areas of my own knowledge about monarchs and milkweed that I wanted to immerse myself in, but that I had not yet done any research on. So as an author, getting to visit the overwintering sites in Mexico, to study the population decline of monarch butterflies, and to understand their mating rituals were all fascinating detours from my everyday research life at Cornell University. The book was incredibly fun to write, and getting to work with artists and historians made it all the more rich. I hope that anybody that has an appreciation for nature, an interest in science, or just a curiosity about the ecology of plants and butterflies will enjoy this book. Working on this project has surely altered the course of my own research, the classes I teach, and how I see the natural world.

Why have you highlighted some of the personalities of the scientists studying monarchs and milkweeds in this book?

AA: One of the most amazing things about monarchs and milkweeds is the scientists who have studied them. They were such remarkable characters, especially those pioneering studies back in the 1950s: tremendously creative, sometimes competitive, and with some of their discoveries worthy of a Nobel prize. Getting to know them, both from their discoveries and their personalities, and how they interacted, has enriched my appreciation for how science is done. It also highlights the meandering and sometimes serendipitous nature of discoveries. I wanted to share the thrill of science, its ups and downs, and the process by which it is done with the curious reader.

Can you share one of your ah-ha! moments from studying monarchs and milkweeds?

AA: One of my favorites was from when I was an assistant professor at the University of Toronto. One day I was eating lunch by myself in a small downtown garden. Just by chance, I happened to sit on a bench beneath a very tall milkweed plant that had a very large monarch caterpillar feeding away. Without giving away all the details, that one hour encounter, in the middle of a city with 3 million people, changed my perspective on monarchs and milkweed forever. It was so unlikely an event, perhaps 1 in a 1,000 that a butterfly had been flying by and happened to lay an egg on this Toronto milkweed, and then a further 1 in 100 chance of that egg hatching and surviving to be that large caterpillar that I could watch it. And probably a 1 in a million event that I would happen to be eating lunch there, that day, to observe the events. In biology one has to work hard, be patient, and occasionally get very lucky! Throughout my studies on monarchs and milkweed, I have had tremendous luck in encountering wonderful biology that has had profound consequences.

Is the monarch butterfly going extinct?

AA: The answer to this very important and timely question is both simple and complex. On the simple side, there is no way the monarch butterfly is going extinct anytime soon. Having said that, the butterfly, and especially the long-distance migration that occurs every fall from Southern Canada and the USA, all the way to Mexico’s highlands in Michoacán, is indeed declining at a rapid pace, and we should all be worried about the sustainability of the annual migration. There’s so much information and misinformation floating around in the news these days about the causes of the monarchs decline. What I’ve tried to do in the book is outline the best knowledge that we have to date and to examine the facts critically, so we can really understand what might be going on. Unfortunately, we don’t have all the answers, but we can reject some of the most prominent explanations for the population decline of the monarch butterfly. As I argue in the book, planting milkweed certainly won’t hurt, but it is unlikely to save the monarchs annual migratory cycle. It is perhaps ironic that I spend eight chapters of the book discussing and detailing the importance of milkweed for monarchs, and nothing could be more true than their intertwined and intense evolutionary battle, but at this stage, and thinking about their conservation, it does not appear that milkweed is what is limiting the monarch’s population. Monarchs will persist for a very long time, but given that they are migratory butterflies that taste their way across North America, their declining population is something we must try to understand. Much more than the monarch is at stake, these butterflies are sentinels for the health of our continent!

Anurag Agrawal is a professor in the Department of Ecology and Evolutionary Biology and the Department of Entomology at Cornell University. He lives in Ithaca, New York. He is the author of Monarchs and Milkweed: A Migrating Butterfly, a Poisonous Plant, and Their Remarkable Story of Coevolution.

Bird Fact Friday – Weekly Warbler: Yellow warbler

Good news for all the birders out there! We are hosting a Warbler Guide App giveaway today on Instagram (princetonupress). Follow us and like our post to enter, and we will be randomly selecting a winner among the participants on Monday, Feb 6.

From page 466-467 in The Warbler Guide:

The yellow warbler has a plain face with round, black eyes. Its stout black bill stands out against its yellow face. There is yellow edging on its wing feathers. Some of the yellow warblers show red streaking in breast; however, the amount of red beast streaking is variable, usually dull or lacking in females. The yellow warbler is a very widespread species: it can be found in low trees and woodland edges, and often in willows or wet areas.

The Warbler Guide
Tom Stephenson & Scott Whittle
Drawings by Catherine Hamilton
Warbler Guide App
Species Account Example: American Redstart Male

Warblers are amwarblerong the most challenging birds to identify. They exhibit an array of seasonal plumages and have distinctive yet oft-confused calls and songs. The Warbler Guide enables you to quickly identify any of the 56 species of warblers in the United States and Canada. This groundbreaking guide features more than 1,000 stunning color photos, extensive species accounts with multiple viewing angles, and an entirely new system of vocalization analysis that helps you distinguish songs and calls.

The Warbler Guide revolutionizes birdwatching, making warbler identification easier than ever before. For more information, please see the author videos on the Princeton University Press website.

More than superstition: Happy Groundhog Day!

The groundhog may have no talent for predicting the arrival of spring, but it surely can enlighten us on animals’ reactions to changing weather patterns. According to biologist Daniel T. Blumstein, celebrating Groundhog Day is about more than a superstition. In the Washington Post, he notes, “Understanding how individual groundhogs respond to environmental change is essential if we want to predict how animals will react to global warming and other human-driven habitat shifts.”

And no worries if Punxsutawney Phil sees his shadow on Groundhog Day, after all, if winter comes, can spring be far behind?

To know more about this mysterious mammal, check out Roland W. Kays and Don E. Wilson’s book Mammals of North America, an indispensable guide for amateur naturalists and professional zoologists alike.


Mammals of North America
Second Edition
Roland W. Kays & Don E. Wilson
Introduction
Mammals of North America APP

Covering 20 species recognized since 2002 and including 13 new color plates, this fully revised edition of Mammals of North America illustrates all 462 known mammal species in the United States and Canada—each in beautiful color and accurate detail. With a more up-to-date species list than any other guide, improved facing-page descriptions, easier-to-read distribution maps, updated common and scientific names, and track and scat illustrations, this slim, light, and easy-to-use volume is the must-have source for identifying North American mammals.

 

 

Bird Fact Friday – Weekly Warber: Northern parula

Welcome back to the warblers!

From page 366-367 in The Warbler Guide:

The northern parula is very small and active. It has bright yellow throat and breast, and green back patch surrounded by blue. It has broken eye-arcs, which look prominent on its plain bluish face, black lores, and white wing bars. The northern parula is an acrobatic feeder, often hanging upside down. Its bill is brightly bicolored, unlike most other warblers. It is featured on the book cover of The Warbler Guide!

The Warbler Guide
Tom Stephenson & Scott Whittle
Drawings by Catherine Hamilton
Warbler Guide App
Species Account Example: American Redstart Male

Warblers are amwarblerong the most challenging birds to identify. They exhibit an array of seasonal plumages and have distinctive yet oft-confused calls and songs. The Warbler Guide enables you to quickly identify any of the 56 species of warblers in the United States and Canada. This groundbreaking guide features more than 1,000 stunning color photos, extensive species accounts with multiple viewing angles, and an entirely new system of vocalization analysis that helps you distinguish songs and calls.

The Warbler Guide revolutionizes birdwatching, making warbler identification easier than ever before. For more information, please see the author videos on the Princeton University Press website.

Bird Fact Friday – Weekly Warbler: Worm-eating

Welcome back to the warblers!

From page 460-461 in The Warbler Guide:

The worm-eating warbler can be identified by its mustard-colored head with four bold black stripes. It has long, pale, and slightly curved bill, and plain, dusky-olive back and wings. The male and female worm-eating warblers look the same in all seasons. The worm-eating warbler is deliberate and acrobatic in its explorations of the understory. It specializes in picking insects from hanging dead leaves.

The Warbler Guide
Tom Stephenson & Scott Whittle
Drawings by Catherine Hamilton
Warbler Guide App
Species Account Example: American Redstart Male

Warblers are amwarblerong the most challenging birds to identify. They exhibit an array of seasonal plumages and have distinctive yet oft-confused calls and songs. The Warbler Guide enables you to quickly identify any of the 56 species of warblers in the United States and Canada. This groundbreaking guide features more than 1,000 stunning color photos, extensive species accounts with multiple viewing angles, and an entirely new system of vocalization analysis that helps you distinguish songs and calls.

The Warbler Guide revolutionizes birdwatching, making warbler identification easier than ever before. For more information, please see the author videos on the Princeton University Press website.

Bird Fact Friday—Weekly Warbler: Black-and-White

Welcome back to the warblers!

As we approach the launch of our long-awaited Warbler Guide App for Android, we’re highlighting some fun facts about the warblers with a new Weekly Warbler feature. Kicking it off today is the black and white warbler.

From page 160-161 in The Warbler Guide:

The black-and-white warbler is distinctive in many features. Its black-and-white crown stripes are diagnostic. It has long and slightly curved bill, very broad white supercilium, and contrasty white wing bars joining wide white tertial edgings. Its black-and-white pattern is striking even in flight. It likes to creep on trunks and limbs, and more interestingly, to creep downward. It is the longest-lived warbler on record, at eleven years.

 

The Warbler Guide
Tom Stephenson & Scott Whittle
Drawings by Catherine Hamilton
Warbler Guide App
Species Account Example: American Redstart Male

 

Warblers are amwarblerong the most challenging birds to identify. They exhibit an array of seasonal plumages and have distinctive yet oft-confused calls and songs. The Warbler Guide enables you to quickly identify any of the 56 species of warblers in the United States and Canada. This groundbreaking guide features more than 1,000 stunning color photos, extensive species accounts with multiple viewing angles, and an entirely new system of vocalization analysis that helps you distinguish songs and calls.

The Warbler Guide revolutionizes birdwatching, making warbler identification easier than ever before. For more information, please see the author videos on the Princeton University Press website.

 

Dalton Conley & Jason Fletcher on how genomics is transforming the social sciences

GenomeSocial sciences have long been leery of genetics, but in the past decade, a small but intrepid group of economists, political scientists, and sociologists have harnessed the genomics revolution to paint a more complete picture of human social life. The Genome Factor shows how genomics is transforming the social sciences—and how social scientists are integrating both nature and nurture into a unified, comprehensive understanding of human behavior at both the individual and society-wide levels. The book raises pertinent questions: Can and should we target policies based on genotype? What evidence demonstrates how genes and environments work together to produce socioeconomic outcomes? Recently, The Genome Factor‘s authors, Dalton Conley and Jason Fletcher, answered some questions about their work.

What inspired you to write The Genome Factor?

JF: Our book discusses how findings and theories in genetics and biological sciences have shaped social science inquiry—the theories, methodologies, and interpretations of findings used in economics, sociology, political science, and related disciplines —both historically and in the newer era of molecular genetics. We have witnessed, and participated in, a period of rapid change and cross-pollination between the social and biological sciences. Our book draws out some of the major implications of this cross-pollination—we particularly focus on how new findings in genetics has overturned ideas and theories in the social sciences. We also use a critical eye to evaluate what social scientists and the broader public should believe about the overwhelming number of new findings produced in genetics.

What insights did you learn in writing the book?

JF: Genetics, the human genome project in particular, has been quite successful and influential in the past two decades, but has also experienced major setbacks and is still reeling from years of disappointments and a paradigm shift. There has been a major re-evaluation and resetting of expectations the clarity and power of genetic effects. Only 15 years ago, a main model was on the so-called OGOD model—one gene, one disease. While there are a few important examples where this model works, it has mostly failed. This failure has had wide implications on how genetic analysis is conducted as well as a rethinking of previous results; many of which are now thought to false findings. Now, much analysis is conducted using data 10s or 100s of thousands of people because the thinking is that most disease is caused by tens, hundreds, or even thousands of genes that each have a tiny effect. This shift has major implications for social science as well. It means genetic effects are diffuse and subtle, which makes it challenging to combine genetic and social science research. Genetics has also shifted from a science of mechanistic understanding to a large scale data mining enterprises. As social scientists, this approach is in opposition to our norms of producing evidence. This is something we will need to struggle through in the future.

How did you select the topics for the book chapters?

JF: We wanted to tackle big topics across multiple disciplines. We discuss some of the recent history of combining genetics and social science, before the molecular revolution when “genetics” were inferred from family relationships rather than measured directly. We then pivot to provide examples of cutting edge research in economics and sociology that has incorporated genetics to push social science inquiry forward. One example is the use of population genetic changes as a determinant of levels of economic development across the world. We also focus our attention to the near future and discuss how policy decisions may be affected by the inclusion of genetic data into social science and policy analysis. Can and should we target policies based on genotype? What evidence do we have that demonstrates how genes and environments work together to produce socioeconomic outcomes?

What impact do you hope The Genome Factor will have?

JF: We hope that readers see the promise as well as the perils of combining genetic and social science analysis. We provide a lot of examples of ongoing work, but also want to show the reader how we think about the larger issues that will remain as genetics progresses. We seek to show the reader how to look through a social science lens when thinking about genetic discoveries. This is a rapidly advancing field, so the particular examples we discuss will be out of date soon, but we want our broader ideas and lens to have longer staying power. As an example, advances in gene editing (CRISPR) have the potential to fundamentally transform genetic analysis. We discuss these gene editing discoveries in the context of some of their likely social impacts.

Dalton Conley is the Henry Putnam University Professor of Sociology at Princeton University. His many books include Parentology: Everything You Wanted to Know about the Science of Raising Children but Were Too Exhausted to Ask. He lives in New York City. Jason Fletcher is Professor of Public Affairs, Sociology, Agricultural and Applied Economics, and Population Health Sciences at the University of Wisconsin–Madison. He lives in Madison. They are the authors of The Genome Factor: What the Social Genomics Revolution Reveals about Ourselves, Our History, and the Future.

Bird Fact Friday — Not so bird brained after all…

From page 161 of Bird Brain:

Bird Brain by Nathan Emery makes the case that birds are not as devoid of intelligence as has previously been thought. In fact, some can even be considered as smart as apes and dolphins. This concludes our Bird Fact Friday feature. Stay tuned for Horse Fact Friday starting in the new year!

Bird Brain
An Exploration of Avian Intelligence
Nathan Emery
With a foreword by Frans de Waal
Introduction

EmeryBirds have not been known for their high IQs, which is why a person of questionable intelligence is sometimes called a “birdbrain.” Yet in the past two decades, the study of avian intelligence has witnessed dramatic advances. From a time when birds were seen as simple instinct machines responding only to stimuli in their external worlds, we now know that some birds have complex internal worlds as well. This beautifully illustrated book provides an engaging exploration of the avian mind, revealing how science is exploding one of the most widespread myths about our feathered friends—and changing the way we think about intelligence in other animals as well.

Bird Brain looks at the structures and functions of the avian brain, and describes the extraordinary behaviors that different types of avian intelligence give rise to. It offers insights into crows, jays, magpies, and other corvids—the “masterminds” of the avian world—as well as parrots and some less-studied species from around the world. This lively and accessible book shows how birds have sophisticated brains with abilities previously thought to be uniquely human, such as mental time travel, self-recognition, empathy, problem solving, imagination, and insight.

Written by a leading expert and featuring a foreword by Frans de Waal, renowned for his work on animal intelligence, Bird Brain shines critical new light on the mental lives of birds.

Bird Fact Friday – Do birds deceive one another?

From page 155 of Bird Brain:

For hundreds of years, con artists have tricked unsuspecting passerby with the shell game, in which a ball is placed under one of three shells and the participant must guess where the ball has ended up after the shells have been moved around. Scrub jays employ a similar tactic when they frequently recache food without necessarily moving the food each time. The trick is meant to deceive potential thieves.

Bird Brain
An Exploration of Avian Intelligence
Nathan Emery
With a foreword by Frans de Waal
Introduction

EmeryBirds have not been known for their high IQs, which is why a person of questionable intelligence is sometimes called a “birdbrain.” Yet in the past two decades, the study of avian intelligence has witnessed dramatic advances. From a time when birds were seen as simple instinct machines responding only to stimuli in their external worlds, we now know that some birds have complex internal worlds as well. This beautifully illustrated book provides an engaging exploration of the avian mind, revealing how science is exploding one of the most widespread myths about our feathered friends—and changing the way we think about intelligence in other animals as well.

Bird Brain looks at the structures and functions of the avian brain, and describes the extraordinary behaviors that different types of avian intelligence give rise to. It offers insights into crows, jays, magpies, and other corvids—the “masterminds” of the avian world—as well as parrots and some less-studied species from around the world. This lively and accessible book shows how birds have sophisticated brains with abilities previously thought to be uniquely human, such as mental time travel, self-recognition, empathy, problem solving, imagination, and insight.

Written by a leading expert and featuring a foreword by Frans de Waal, renowned for his work on animal intelligence, Bird Brain shines critical new light on the mental lives of birds.

Bird Fact Friday – Birds storing food

From page 148 of Bird Brain:

Among social birds who cache their food, it is difficult to keep their hiding places a secret from other birds in their group. To get around this, they will move caches around to make the final hiding place difficult to determine. This strategy may have occurred accidentally in the past and resulted in a greater yield of recovered caches, or it may be a result of a deliberate attempt to deceive potential thieves.

Bird Brain
An Exploration of Avian Intelligence
Nathan Emery
With a foreword by Frans de Waal
Introduction

EmeryBirds have not been known for their high IQs, which is why a person of questionable intelligence is sometimes called a “birdbrain.” Yet in the past two decades, the study of avian intelligence has witnessed dramatic advances. From a time when birds were seen as simple instinct machines responding only to stimuli in their external worlds, we now know that some birds have complex internal worlds as well. This beautifully illustrated book provides an engaging exploration of the avian mind, revealing how science is exploding one of the most widespread myths about our feathered friends—and changing the way we think about intelligence in other animals as well.

Bird Brain looks at the structures and functions of the avian brain, and describes the extraordinary behaviors that different types of avian intelligence give rise to. It offers insights into crows, jays, magpies, and other corvids—the “masterminds” of the avian world—as well as parrots and some less-studied species from around the world. This lively and accessible book shows how birds have sophisticated brains with abilities previously thought to be uniquely human, such as mental time travel, self-recognition, empathy, problem solving, imagination, and insight.

Written by a leading expert and featuring a foreword by Frans de Waal, renowned for his work on animal intelligence, Bird Brain shines critical new light on the mental lives of birds.

10 Facts from How Men Age

AgeIn How Men Age, Richard Bribiescas is one of the first to bring evolutionary biology into the conversation of male aging, describing how it has contributed to the evolution of the human species as a whole. The book makes fascinating reading for anyone who has wondered about the purpose of male post reproductive years. From oxidative stress to loss of hormonal plasticity, here are a few things you may not have known about male aging:


1. Compared to other animals, the human life span is much longer than one would predict. Life span is usually correlated with female reproductive life span; that is, when females cease reproducing, it is usually a signpost that mortality for the species is imminent. However, in humans about a third of female life is post-reproductive.

2. Men tend to die at higher rates at younger ages than do women from infancy, through adulthood, and into old age, regardless of culture or environmental context.

3. Sex ratios in humans at birth are biased towards males, but the reason remains a mystery. There may be an unequal number of X- and Y-bearing sperm, the fertilization process might be somehow biased, or there might be an unequal attrition during gestation, all of the above, or something else entirely.

4. In males, muscle serves two purposes unique to their sex. It augments their ability to reproduce by supporting competition and attractiveness and it is an important source of overall energy regulation. More so than other types of muscle, skeletal muscle is sexually dimorphic, which means that relative mass, form, and function differ between men and women.

5. The type of muscles men tend to have are type II, which supports quick movements and bursts of strength. The muscle tends to be in their upper body, including in their shoulders, arms, and back.

6. Men lost muscle tone as they age because of declining testosterone, lower metabolic rates, and shifts in other areas of the hypothalamic-pituitary-testicular hormone axis.

7. After a certain age, men living more urbanized, sedentary lifestyles exhibit a more notable drop in testosterone compared to other men around the world.

8. Testosterone tends to peak in the second decade of life and then slowly decline until the age of 40, after which it is pretty much stable for the rest of a man’s life.

9. As men age, their bodies become less sensitive to environmental and energetic cues and less malleable and responsive to surrounding change. This loss of hormonal plasticity causes the body to become less efficient at putting on muscle and regulating fat accumulation.

10. Oxidative stress is one contributing factor to aging. Men tend to have higher metabolic rates than women, and therefore have the capacity to generate more oxidative stress over their lifetimes. This might contribute to shorter lifespans in men.

To delve into this engaging subject further, pick up a copy of How Men Age.

Oswald Schmitz on “new ecology”: How does humankind fit in with nature?

Schmitz Ecology has traditionally been viewed as a science devoted to studying nature apart from humans. But humankind is singlehandedly transforming the entire planet to suit its own needs, causing ecologists to think differently about the relationship between humans and nature. The New Ecology: Rethinking a Science for the Anthropocence by Oswald Schmitz provides a concise and accessible introduction to what this “new ecology” is all about. The book offers scientific understanding of the crucial role humans are playing in this global transition, explaining how we can ensure that nature has the enduring capacity to provide the functions and services on which our existence and economic well-being critically depend. Recently, Schmitz took some time to answer a few questions about his new book.


The term Anthropocene is cropping up a lot nowadays in discussions about the environment. What does this term refer to?

OS: The Anthropocene essentially means the Age of Humans. Science has characterized the history of the Earth in terms of major events that have either shaped its geological formations or have given rise to certain dominant life forms that have shaped the world. For example, the Mesozoic is known as the Age of the Dinosaurs, the Cenozoic includes the Age of Flowering Plants, Age of Insects, Age of Mammals and Birds. The Anthropocene characterizes our modern times because humans have become the dominant life form shaping the world.

You’ve written several books about ecology. What’s different about this one?

OS: My goal is to communicate the exciting scientific developments and insights of ecology to a broad readership. I hope to inspire readers to think more deeply about humankind’s role as part of nature, not separate from it, and consider the bigger picture implications of humankind’s values and choices for the sustainability of Earth. As such, the intended audience is altogether different than my previous books. My previous books were technical science books written specifically for ecologists or aspiring ecologists.

What inspired you to write this particular book?

OS: The ecological scientific community has done a great job of conducting its science and reporting on it in the scientific literature. That literature is growing by leaps and bounds, describing all manner of fascinating discoveries. The problem is, all that knowledge is not being widely conveyed to the broader public, whose tax dollars are supporting much of that research and who should be the ultimate beneficiaries of the research. Writing this book is my way of explaining to the broader public the incredible value of its investment in ecological research. I wrote it to explain how the scientific findings can help make a difference to people’s livelihoods, and health and well-being.

What is the main take-home message?

OS: I’d like readers to come away appreciating that ecological science offers considerable means and know-how to help solve many of the major environmental problems facing humankind now and into the future. It aims to dispel the notion, often held in society, that ecology is simply a science in support of environmental activism against human progress, one that simply decries human impacts on the Earth. This book instead offers a positive, hopeful outlook, that with humility and thoughtful stewardship of Earth, humans can productively engage with nature in sustainable ways for the mutual benefit of all species—humans included—on Earth.

Oswald Schmitz is the Oastler Professor of Population and Community Ecology in the School of Forestry and Environmental Studies at Yale University. His other works include Resolving Ecosystem Complexity (Princeton). His most recent book is The New Ecology: Rethinking a Science for the Anthropocence.