The Song of the Dodo: Island Biogeography in an Age of Extinctions, by David Quammen

Colorado Environmental Law Journal Colorado Environmental Law Journal

Volume 7Number 2

Article 8

The Song of the Dodo: Island Biogeography in an Age of The Song of the Dodo: Island Biogeography in an Age of

Extinctions, by David Quammen Extinctions, by David Quammen

Andrew C. Mergen

Book Review

THE SONG OF THE DODO: ISLAND BIOGEOGRAPHY IN AN AGE OF EXTINCTIONS. By David Quammen, New York, NY; Scribner, 1996. Pp. 702; $32.50 hardcover.

Andrew C. Mergen'

Assume for the moment that after years of successful legal practice you have been appointed to the position of Secretary of Environment for the equatorial Republic of Tropix. The President has asked you to advise him on a strategy for preserving one of the nation's most endangered creatures, the Giant Monkey-Eating Eagle.' This large raptor is symbolically important to the people of Tropix. The eagle is often evoked as a symbol of the nation's strength, and the Republic's national soccer club is named for the eagle. Indeed, images of this animal abound in the Republic's capitol. Unfortunately, the creatures themselves are quite rare in the wild. Logging and agricultural encroachment have greatly reduced the habitat available to the eagle. The forest environment necessary to the eagles' survival exists only as patchwork across the nation. Estimates vary, but fewer than one hundred eagles are presumed to persist in their native habitat. The President is prepared to use his executive authority to create one or perhaps several protected reserves for these birds, but only if their survival can be guaranteed.'

A legal education in the United States has made you familiar with American environmental laws and a baffling number of acronyms, but left you largely ignorant of the fundamental principles of biology, let alone the specific resource needs of a giant monkey-eating bird.' What to do? Well, after you commission the advice of the world's experts on the eagle, I recommend sitting down with David Quammen's scholarly yet accessible book, The Song of the Dodo.- Island Biogeography in an Age of Extinction.4

The title of the book takes its name from the large flightless bird of the island of Mauritius in the Indian Ocean. The Dodo was extinct by the end of the 17th century (before anyone could record its song), largely as a result of unthinking human action.' Conservation law and policy have often failed to protect endangered animals and habitats because of ignorance.'Island biogeography, properly understood, should greatly improve environmental decision making. Quanmen's book provides an excellent history and explanation of island biogeography and its implications for conservation law and policy. Moreover, its implications for rare creatures and their ecosystems should goad us into immediate action.

The study of biogeography has a long history. Athanius Kircher (16021680), a German Jesuit, devoted his life to calculating the size of Noah's Ark and estimating the number of animal species the Ark could accommodate.' Kircher understood the Bible to be a record of actual events, and his work represents an early example of the troubling implications biogeography has had for its observers. As Kircher worked at his calculations, foreign travelers were bringing back to Europe a multitude of previously unknown animals. Without an alternative explanation for this biological diversity,

Kirchner had to fit all of these creatures into his image of the biblical Ark.8 Consequently, the reproductions of the Ark that accompanied Kircher's treatise look more like a tenement than a watercraft.9

Although Quammen mentions Kircher, his book begins with an examination of the life and theories of a more modem scientist, Alfred Russel Wallace (1823-1913). After Charles Darwin, Wallace is arguably the greatest naturalist of the 19th century. Wallace, independently of Darwin, also arrived at a theory of natural selection, the concept that lies at the heart of evolutionary theory. Quammen savors telling Wallace's story; Darwin's five year voyage on the Beagle is, of course, well known, but Wallace's travels were, in many respects, more fantastic. Quanmen's treatment of Wallace's often solitary travels through both Amazonia and the Malaysian Archipelago (now Indonesia) is a highly readable blend of scientific history, journalism, and travel writing. Thus, as Quammen retraces Wallace's steps, his travel reporting is lively and vivid, as is his account of Wallace's adventures. After four years of collecting and cataloging natural history specimens in South America, and keeping meticulous journals, Wallace lost virtually everything when his ship sank. In Quammen's telling, Wallace despairs over this unthe specimens were not only his passion but also his fathomable loss livelihood -

for only a single night.0

Although Quammen champions Wallace as a scientist and a man, he does not neglect Darwin or Darwin's contributions to biogeography." The observations of both men established the foundations of evolutionary theory and island biogeography. Darwin and Wallace were keen observers of the natural world who were fortunate to travel widely. Wallace observed on his travels that old islands supported far more endemic species than young islands. One possible explanation for this observation is that older islands, because of prolonged isolation, have produced a larger number of evolutionary novelties.2

Quammen also examines the relationship between such observations and the development of evolutionary theory. According to legend, Darwin, while traveling in the Galapagos, observed subtle differences in the beaks of the various finch species that inhabited the island chain and concluded right there and then that these varieties evolved from a single ancestor. The truth, Quammen observes, is more complicated. It was not until years after Darwin returned from his voyage and consulted with a prominent ornithologist that he began to appreciate the significance of the finches.3 Although the role of the Galapagos finches in the development of evolutionary theory is frequently overstated, there is no doubt that the study of the birds ultimately confirmed and enhanced Darwin's thinking about evolution." Some of Quammen's discussion will be familiar to readers of the recent Pulitzer Prize winning book by Jonathan Weiner, The Beak of the Finch, but the tale does not suffer from its retelling.'5 The story of Darwin, the Galapagos finches, and evolution has much to teach us about how science is done, and Quammen's version is fresh and lively.

Quammen explains, with equal adeptness, the contributions to evolution and biogeography made by 20th century biologists like Ernst Mayr and Frank Preston. Quammen also provides a lucid explanation of Robert MacArthur and Edward 0. Wilson's The Theory of Island Biogeography, and discusses the profound effect that work has had on the biological sciences. 16

MacArthur and Wilson's book, and the countless studies and debates it has spawned, are important to environmental lawyers and policymakers because island biogeography is an important part of the new science of conservation biology, a mission-oriented science with the purpose of providing principles and tools for preserving biological diversity. '7 MacArthur and Wilson's theory, reduced to its basics, states that the species lost from an island, during a given span of time and under ordinary circumstances, are roughly equal to the number of species gained by the same island over

the same span of time. Species are lost through extinction and gained through speciation (very rarely) and immigration (far more commonly). Unless the island itself is of very recent origin or has undergone a sudden disruption, the rates of losses and gains tend to cancel each other out. Thus, the number of resident species remains steady while the roster of identities changes continually. MacArthur and Wilson referred to this principle as the equilibrium theory.8

The publication of MacArthur and Wilson's theory spawned considerable research into island communities. Two points quickly became clear. First, not all island communities fit the equilibrium model because some communities had been so physically isolated that they had experienced no immigration of new species, only the extinction of existing ones. Second, not all "island" communities are actually islands. For instance, caves and mountaintops are, like islands, insular ecological communities.9 Furthermore, it soon became apparent that the study of island biogeography has significant implications for the conservation movement. Today, national parks, refuges, and other isolated patches of wilderness are also "islands" in a sea of development. If these "islands" are highly insulated from the larger ecosystem, they will not be able to sustain themselves, and many species in the refuge or "island" will become extinct.0

Biologists quickly developed principles for park and refuge size based on what they knew about island biogeography. Initially, there was little agreement about what conservation principles could be inferred from biogeography. Quamenn reviews in detail the so-called "SLOSS" debate. This debate focused on whether biological diversity is best preserved in a Single Large refuge Or Several Small refuges (hence SLOSS). The SLOSS debate was heated, in part because the scientific community was aware that environmental policymakers were watching the debates carefully. Quammen mentions several nations that almost abandoned conservation efforts directed at endangered wildlife because, in the context of these scientific theories, those nations had concluded that the endangered species were doomed to extinction.

2'

Eventually, scientists realized that the question of biological preservation was bigger than the SLOSS formulation. The conservation debate for a particular species must also include an analysis of the minimum viable population for that species and the genetic health of that population. In addition,

the effects of extrinsic factors like habitat disturbances, fires, and disease must also be considered.2 These factors reflect the growing realization among scientists that there are no easy answers and that the best solution may be the creation of many large refuges. Despite the emerging complexity of island biogeography, it is clear from the SLOSS debate that successful conservation measures will require an integration of biological science and environmental law and policy.23

Thus, Quammen's book serves as another reminder that our legal and policy-making institutions need to respond promptly to the ongoing revolution in biology and ecology. No longer do ecologists view the "natural" world as unchanging when undisturbed by humankind. Indeed, it is well understood that throughout the history of life there has been a background level of species extinctions as well as natural disasters or cataclysms which upset entire ecosystems." Legal, scientific, and cultural commentators have all recently stressed the need to incorporate this new science into our world view.

Environmental conservation cannot be directed at freezing nature in time to create a kind of static museum display, but must reflect a dynamic evolving world that includes humankind and calamity. However, as the environmental historian Donald Worster has explained, not all change is the same, nor is all change equal.26 The age of anthropogenic extinction in which we currently live is not one that we have to accept. Informed by the new science, our laws and policies must seek to preserve the diversity that constitutes a changing and evolving natural world. Quammen's book presents well the dynamic nature of ecosystems and the immorality of the current age of extinction.

Finally, Quammen's book is useful to lawyers and policymakers as an exploration of the current age of extinction and as a rejoinder to ill-conceived ecological optimism. In 1995, Gregg Easterbrook's massive volume, A Moment on Earth: The Coming Age of Environmental Optimism" was published to great fanfare including a conference devoted to its implications at the Yale Law School. Easterbrook looks at a large number of environmental controversies and debates and concludes that the "arrow of the human prospect points upward."2 Easterbrook's book, although rightly criticizing environmental organizations for some shrill and hyperbolic campaigns, is ultimately a failure, since it fails to consider the bulk of the scientific evidence that, especially in the developing world, conditions are rapidly deteriorating, and is too quick to conclude that things will get better. Easterbrook's Panglossian approach allows him to stop his inquiry into environmental problems with some piece of good news or a success story;29 Quammen probes more deeply and thus his book serves as an important counterweight to Easterbrook's superficial analysis.

The tone of Quarnmen's book is neither shrill nor exaggerated, yet its conclusions and implications are somber for those who care about wild places and animals. Towards the end, the book meditates on an increasingly fragmented world.

How many grizzly bears occupy the North Cascades ecosystem, a discrete patch of montane forest along the northern border of the state of Washington? Not enough. How many European brown bears are there in Italy's Abruzzo National Park? Not enough. How many panthers in Big Cypress Swamp? Not enough. How many Asiatic lions in the Forest of Gir? Not enough. How many indri [a species of lemur] at Analamazaotra? Not enough. And so on. The world is in pieces.3"

This brings us back to Tropix and the Giant Monkey-Eating Eagle. At the outset of this review I explained that fewer than one hundred eagles are presumed to survive. The problem with such a small population is that it is prone to genetic deterioration. But all is not lost. In The Song of the Dodo Quammen tells the story of the Mauritius kestrel, also a raptor. Its population dropped well below fifty and there seemed no chance it could recover.' Indeed, a prominent conservationist suggested that no more money be spent on the bird because it was unlikely to survive.3 Largely through the efforts of one man, Carl Jones, the kestrel has been preserved." But Quammen appends a cautionary note to this wonderful story: because the bird was always quite rare, it was less subject to the effects of genetic deterioration than other species of animals. An animal species that had once been common but had more recently been reduced to a few individuals would not have recovered.3

Let us imagine that the Giant Monkey-Eating Eagle was also quite rare even before its habitat was destroyed. In that case, with quick action, perhaps the eagle, like the kestrel, can be preserved. The story of the kestrel teaches that conservation policies must be informed by an understanding of sophisticated biological concepts. The Song of the Dodo is an excellent and entertaining introduction to those concepts for the layperson.

--- FOOTNOTES ---

Part of the Environmental Law Commons

t Mr. Mergen is the 1996 El Paso Natural Gas Law Fellow at the Natural Resources Law Center, University of Colorado School of Law. He would like to thank El Paso and the Natural Resources Law Center for their support. Mr. Mergen is on leave from the Appellate Section, Environment and Natural Resources Division, US Dept. of Justice.

1. Tropix and the Giant Monkey-Eating Eagle are, of course, creations of the

reviewer.

2. The use of executive authority to withdraw public lands from entry and to create preserves and parks is well established in the United States. See GEORGE C. COGGINS ET AL., FEDERAL PUBLIC LAND AND RESOURCE LAW 291-94 (3d ed. 1993) (discussing modem withdrawal practice under the Federal Land Policy and Management Act of 1976, 43 U.S.C. § 1714 (1994 . For purposes of this review, similar powers are imputed to the president of the fictitious Tropix.

The creation of a park or refuge for the immediate preservation of a single species is not uncommon. Several American refuges and parks were established to preserve particular species, including the California condor, the saguaro, Kirtland's warbler and redwoods. Michael Soule & Daniel Simberloff, What Do Genetics and Ecology Tell Us About the Design of Nature Reserves?, in ENVIRONMENTAL POLICY AND BIODIVERSITY 55, 55 (R. Edward Grumbine ed., 1994).

3.

It is, of course, well known that American environmental law is "packed with bizarre terms and opaque acronyms." Carol M. Rose, Rethinking Environmental Controls: Management Strategies for Common Resources, 1991 DUKE L.J. 1, 1. See also Richard J. Lazarus, Meeting the Demands of Integration in the Evolution of Environmental Law: Reforming Environmental Criminal Law, 83 GEO. L.J. 2407,2430-31 (1995) (arguing that the large number of acronyms used in environmental law contribute to its complexity). Professor Lazarus also contends that few environmental lawyers have even "the dimmest comprehension of the ... biological processes .. .that serve as the true denominators of environmental protection standards." Id. at 2430.

4. DAVID QUAMMEN, THE SONG OF THE DODO: ISLAND BIOGEOGRAPHY IN AN

AGE OF EXTINCTIONS (1996). 5. Id. at 262-75. 6. In his book, for example, Quammen tells the story of the Tasmanian Tiger or Thylacine, a wolf-like marsupial predator. In 1936, two months before the last known Thylacine died, the government of Tasmania declared it a protected species. Id. at 27987.

7. See JANET BROWNE, THE SECULAR ARK: STUDIES IN THE HISTORY OF BIOGE-

OGRAPHY 4-5 (1983).

8. Id. at 5. 9. Id. at 8. 10. QUAMMEN, supra note 4, at 71. 11. Quammen appears to relish Wallace's story, in part because Wallace, unlike Darwin, did not come from a privileged background. Consequently Wallace's brilliance in the sciences seems more extraordinary in an era when many intellectual pursuits were the province of the monied classes who had more time to pursue seemingly abstract matters. As the historian and paleontologist Stephen Jay Gould has noted, the financial and familial support that Darwin enjoyed were important to the realization of his genius. Stephen J. Gould, Why Darwin?, N.Y. REv. BOOKS, Apr. 4, 1996 at 10, 14 (book review).

12. QUAMMEN, supra note 4, at 49.

13. QUAMMEN, supra note 4, at 224-30. 14. QUAMMEN, supra note 4, at 226. 15. JONATHAN WEINER, THE BEAK OF THE FINCH 17-36 (1994). Weiner's book, an exploration of a current study of evolutionary change among the Galapagos finches, like Quammen's The Song of the Dodo, has much to offer environmental lawyers and policymakers. The book's implications for law and policy have recently been explored by Jonathan B. Wiener (not related to Jonathan Weiner) in an essay published in the Ecology Law Quarterly. See Jonathan B. Wiener, Law and the New Ecology: Evolution, Categories, and Consequences, 22 ECOLOGY L.Q. 325 (1995) (book review).

16. ROBERT MACARTHUR & EDWARD 0. WILSON, THE THEORY OF ISLAND BIO-

GEOGRAPHY (1967).

17. Michael E. Soule, What is Conservation Biology?, in ENVIRONMENTAL POLICY

AND BIODIVERSITY, supra note 2, at 35, 35.

18. QUAMMEN, supra note 4, at 414-15. 19. QUAMMEN, supra note 4, at 436-40. 20. QUAMMEN, supra note 4, at 442-47. 21. QUAMMEN, supra note 4, at 480.

22. QUAMMEN, supra note 4, at 540-41. 23.

In the United States this process has already begun. The US Forest Service has promulgated regulations governing the development of forest management plans that require the Forest Service to manage habitat "to maintain viable populations of existing native and desired non-native vertebrate species." 36 C.F.R. § 219.19 (1996). For litigation involving the interpretation of these regulations and the application of principles of island biogeography to forest planning, see Sierra Club v. Marita, 843 F. Supp. 1526 (E.D. Wis. 1994), aff'd, 46 F.3d 606 (7th Cir. 1995).

24. QUAMMEN, supra note 4, at 605-06. 25. See Judy L. Meyer, The Dance of Nature: New Concepts in Ecology, 69 CHI.-

KENT L. REV. 875, 875-82 (1994); Donald Worster, Nature and the Disorder of History, 18 ENVTL. HIST. REV. 1 (1994); Weiner, supra note 15, at 355-57.

26. Worster, supra note 25, at 14. See also William Cronon, The Trouble with Wilderness; or Getting Back to the Wrong Nature, in UNCOMMON GROUND: TOWARD REINVENTING NATURE 69, 89 (William Cronon ed., 1995) (arguing against a dualistic view of wilderness as separate from humankind but asserting that "deep reflection and respect must accompany each act of [land] use").

27. GREGG EASTERBROOK, A MOMENT ON THE EARTH: THE COMING AGE OF

ENVIRONMENTAL OPTIMISM (1995).

28. Id. at 697. 29. Consider the following example. In his discussion of endangered wildlife Easterbrook observes that "contrary to the conventional wisdom that species are being assailed and abandoned by heartless humans, women and men are already striving on multiple fronts to save other creatures." Id. at 553. One example Easterbrook gives is the Florida manatee. Florida has imposed low speed limits in coastal waters to protect the manatee. Easterbrook tells us these speed limits are "extremely unpopular," but are in force anyway in order to protect the manatee from collisions. As I write, in April of 1996, over 221 manatees have been found dead in Florida's coastal waters, and more than half of these animals are apparently victims of a mysterious ailment. Red Tide is a Suspect in Deaths of Manatees Off Florida Coast, N.Y. TIMES, Apr. 11, 1996, at A18. Scientists studying this phenomenon have indicated that human activity may have already so reduced the manatee population that the species will not be able to recover from this epidemic. Id. Given this situation, it is hard to take much solace in boating speed limits.

30. QUAMMEN, supra note 4, at 549.

31. QUAMMEN, supra note 4, at 550. 32. QUAMMEN, supra note 4, at 551. 33. QUAMMEN, supra note 4, at 555-59. 34. QUAMMEN, supra note 4, at 567.