Fundamentals of Conservation Biology. Malcolm L. Hunter, Jr.
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were: Marquez et al. (1991), Milinkovitch et al. (2004), Gibbs et al. (2014), and personal observations.
Summary
People who care about nature and the natural resources we obtain from nature, such as clean air and clean water, come with many labels: conservationists and preservationists, environmentalists and ecologists. Although these people share many goals, their priorities can differ. For example, conservationists advocate the careful use of natural resources, whereas environmentalists often emphasize maintaining an uncontaminated environment. The history of conservation has a recurring theme: people being forced to limit their use of natural resources more and more as human populations grow and technological sophistication increases. Conservation history is marked by practices and laws regulating our use of natural resources, but more fundamental is the evolution of our ethical attitudes toward nature and its intrinsic and instrumental values. Three ethical positions underpin our motivation and practices to conserve biodiversity: (1) the Romantic‐Transcendental Preservation Ethic (briefly, nature is best used for spiritual purposes); (2) the Resource Conservation Ethic (nature is natural resources to be carefully developed for human purposes); and (3) the Evolutionary‐Ecological Land Ethic (people are part of nature and have both the right to change it and a responsibility for respecting the intrinsic value of other species and ecosystems in general). Conservation biology is the applied science of maintaining the Earth’s biological diversity. It differs from basic biologic sciences because it reaches out to economics, law, education, politics, philosophy, and other subjects that shape the human world within which conservation must operate. It differs from traditional natural resource sciences because it places relatively greater emphasis on all forms of life and their intrinsic value, compared with other natural resource sciences, which typically focus on relatively few species with high instrumental (usually economic) value.
FURTHER READING
A comprehensive world history of conservation would be voluminous but some succinct overviews are available (Hughes 2009; Simmons 2008). If you want more depth there are whole encyclopedias (Krech et al. 2004), even one covering just the United States (Brosnan 2011). Many books cover certain times, phenomena, and places; for example, the sixteenth to eighteenth centuries (Richards 2003), the twentieth century (McNeill 2000), European colonization (Grove 1995), collapse of civilizations (Diamond 2005), Canada (MacDowell 2012), Latin America (Miller 2007), the Mediterranean (Hughes 2005), and the United States (Merchant 2007). Also see the journal Environmental History. Articles by Soulé (1985), Callicott (1990), and Jacobson (1990) form a foundation for the latter parts of the chapter and merit further reading. For relevant websites, check out the Society for Conservation Biology’s website at conbio.org and some of the major international conservation groups at www.iucn.org, wwf.org, www.nature.org, www.conservation.org, and www.worldwildlife.org.
TOPICS FOR DISCUSSION
1 Do you think of yourself primarily as a conservationist, environmentalist, ecologist, or preservationist, or none of these? Why?
2 Which of the three ethics discussed do you think will be predominant 50 years from now? Why? Would you feel comfortable promoting one of these ethics among your friends and family?
3 Name some organizations that exemplify each of the three ethics today. Have any of these organizations changed their philosophy?
4 Can you identify examples of how each of the disciplines in Fig. 1.4 has contributed to conservation of a specific species in danger of extinction?
CHAPTER 2 What Is Biodiversity?
A tropical forest ringing with a cacophony of unseen frogs, insects, and birds; a coral reef swirling with schools of myriad iridescent fishes; a vast tawny carpet of grass punctuated by herds of wildebeest and other antelope – these images are well known, and for many people they all revolve around a central issue and a single word: “biodiversity” (Fig. 2.1). Some have argued that “biodiversity” is too vague and trendy a word to be useful, but it does succinctly imply a fundamental idea: life on earth is extraordinarily diverse and complex. This idea is not as well captured in other words such as “nature” or “wild life.” Furthermore, “biodiversity” entered the public vocabulary at a time when the global scope of threats to life on Earth became apparent; thus, to many people, the term carries a conviction to stem the loss of the planet's life‐forms.
Figure 2.1 There are few places where biodiversity is as conspicuous as a coral reef.
(Hans Chehaiber/Flickr/CC BY 1.0)
Definitions of biodiversity usually go one step beyond the obvious – the diversity of life – and define biodiversity as the variety of life in all its forms and at all levels of organization. “In all its forms” reminds us that biodiversity includes plants, invertebrate animals, fungi, bacteria, and other microorganisms, as well as the vertebrate animals that garner most of the attention. “All levels of organization” indicates that biodiversity refers to the diversity of genes and ecosystems, as well as species diversity. The idea that biodiversity has levels of organization introduces a complexity that we will explore in the next three chapters, “Species Diversity,” “Ecosystem Diversity,” and “Genetic Diversity,” after a brief overview here. (For a novel approach to understanding biological complexity, see Kim et al. [2019] and their analysis of biochemical networks that reach from individual organisms to the whole biosphere.)
Species, Genes, and Ecosystems
It is easiest to comprehend the idea of maintaining biodiversity in terms of species that are threatened with extinction. We know about blue whales, giant pandas, and whooping cranes, and we would experience a sense of loss if they were to disappear, even though most of us have never encountered them except as digital representations in an electronic medium. For most mosses, lichens, fungi, insects, and other obscure species it is much harder to elicit concern. Nevertheless, many people are prepared to extend some of the feelings they have for whales, pandas, and cranes to species they do not know, as an expression of their belief that all species have some intrinsic value.
Genes can also be hard to understand and appreciate. These self‐replicating pieces of DNA that shape the form and function of each individual organism are the organism’s fundamental blueprint, but also important are water, oxygen, and thousands of other molecules. It is not the genes themselves that conservation biologists value; it is the diversity that they impart to organisms that is so essential. If two individual strawberry plants have a different set of genes, one of them might be better adapted to fluctuations in water availability and thus would be more likely to survive a period of climate change. One of them might be less susceptible to damage from ozone and other types of air pollution. The fruit of one might be more resistant to rotting and therefore its progeny might prove useful to strawberry breeders and farmers. Perhaps the fruits simply taste or look different and thereby provide aesthetic diversity. It is these expressions of genetic diversity that we value. The diversity of life is rooted in genetic differences among individuals and the processes of evolution that amplified and shaped these differences among populations to generate distinct species and ultimately the higher taxonomic levels: genera, families, orders, and so on.
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