3.4 Why biodiversity matters: valuing biodiversity 30
3.4.1 Use values of biodiversity: utilitarianism 31
3.4.1.1 Direct use values: the resource-based argument 31
Direct use values are those concerned with the enjoyment or satisfaction received directly from biodiversity (Blackmore and Reddish, 1996; Maynard et al, 2014). This kind of value is the easiest to appreciate as many people value things largely for their direct utility for humans (Noss and Cooperrider, 1994; Pinto et al, 2014). Noss and Cooperrider (1994) further argue that, although the direct use values are incomplete as a justification for saving biodiversity, such values are real as shown below.
Food: Food is arguably the most important direct use of biodiversity (Belk and Borden, 2008;
Brussaard et al, 2010; Kunin and Lawton, 1996; Phalan et al, 2011; Sangeethapriya and Siddhuraju, 2014). This food takes forms that include vegetables, fruits, nuts, grains, meat, honey, and adjuncts to food in the form of food colourants, flavourings and preservatives (Gaston and Spicer, 2004; Russell et al, 2011; Sandava et al, 2011). Of the estimated 300 000 species of flowering plants, about 12 500 are considered to be edible to humans, although occasional use may embrace a much larger number, with around 200 plant species having been domesticated for food (Gaston and Spicer, 2004; Maxted et al, 2010). Wild food sources still play a significant role in meeting the nutritional needs of people in many of the world’s poorest nations (Akinnifesi et al, 2006; Chavas, 2009; Kunin and Lawton, 1996; Maxted et al, 2010; Sangeethapriya and Siddhuraju, 2014; Scho¨nfeldt and Pretorius, 2011; Shumsky et al, 2014; Sukara, 2014; Uusiku et al, 2010; Vedeld et al, 2007). Di Falco and Chavas (2009) have reported on the value of biodiversity as insurance against yield variability and also against total crop failure. Even in the developed world where most of the foods eaten come from domesticated species, food supplies are critically dependant on wild populations, and a
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significant percentage continues to be foraged from the wild (Groombridge 1992; World Bank, 2007a).
The diversity of organisms exploited for food remains narrow when compared with their overall diversity, leaving significant potential for further exploitation (Baumgartner and Quaas, 2008; Belk and Borden, 2008; Gaston and Spicer, 2004; Nesbitt et al, 2010; UNDP/
UNEP/ World Bank/ WRI, 2000; Zenteno et al, 2013). This gap is, however, being closed indirectly through the use of wild species and varieties to supply genes for the improvement of cultivated and domesticated species for increasing yields, tolerances, vigour, and disease and pest resistance (Gaston and Spicer, 2004; Maxted et al 2010). Thus, wild animal and plant species provide an enormous reservoir of genetic diversity which is the foundation of agriculture and provides for its continued support (Maxted et al, 2010).
Medicine: The World Health Organisation (WHO, 1998) defines human health as a state of total physical, mental and social well-being and not just the absence of disease or infirmity.
In addition to providing sustenance as shown above, biodiversity plays other direct and indirect roles in maintaining the health of the human population (World Bank, 2007a).
Vira and Kontoleon (2010) identify two main avenues through which biodiversity provide a means for mediating health risk for the poor. The first has to do with the impact that biodiversity has on reducing the risk of infectious diseases, while the second has to do with biodiversity as a source of accessible medicinal regimens which are not only curative but are also preventive, thereby reducing health risks (Chivian and Bernstein, 2008; Johns, 2006;
Vira and Kontoleon, 2010). At the ecosystem level, biodiversity produces the appropriate balance between predators and prey, hosts, vectors and parasites which allows for appropriate controls and checks for both the spread of endemic infectious diseases as well as resistance towards invasive pathogens (Vira and Kontoleon, 2010). Ash and Jenkins (2007) identify many diseases that are particularly dependent on changes in ecosystem biodiversity, with many of these diseases being particularly relevant to the poor including malaria, schistosomiasis, meningitis, cholera, dengue and lymphatic filariasis. Biodiversity not only plays the role of reducing the risk of such diseases spreading within an ecosystem and the human populations within it, but also reduces the risk of allowing invasive diseases from entering a particular system (Vira and Kontoleon, 2010). For example, Ash and Jenkins (2007) reported that cholera, kala-azar, and schistosomiasis have not established in the biodiverse Amazonian forest ecosystem in spite of human migration and settlements.
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Biodiversity has proven to be an important source of traditional medicines for people in developing countries, particularly those in remote and normally more poverty-stricken areas of the developing world where access to formal health care is limited (Cordell, 2014; Shah et al, 2014; Vira and Kontoleon, 2010). It is estimated that approximately 75% of the world’s population depends primarily on traditional medicines gathered from wild natural products (Vira and Kontoleon, 2010). Indeed, natural products have long been recognised as an important source of therapeutically effective medicines in many parts of the world (Harvey, 2000). Though traditional medicines may not be as effective as scientifically tested drugs, they provide a cost-effective and accessible option in poverty stricken-communities (Ash and Jenkins, 2007; Cordell, 2014; Shah et al, 2014; Vira and Kontoleon, 2010).
In addition, biodiversity has played, and continues to play, a significant role in modern medicine (Amirkia and Heinrich, 2014; Nair et al, 2011; Sukara, 2014; Szewczyk and Zidorn, 2014). For example, of 520 new drugs approved between 1983 and 1994, 39% were natural products or were derived from them (Gaston and Spicer, 2004). Moreover, of the 20 best- selling non-protein drugs in 1999, 9 were derived directly or indirectly from natural products, with combined annual sales of more than US$16 billion (Gaston and Spicer, 2004). Noss and Cooperrider (1994) note that nearly 3 000 antibiotics have been derived from microorganisms. Twenty three percent of the compounds in the 150 most commonly prescribed drugs in the USA in the 1990s came from animals while, since the mid-1980s, over 2 500 medically significant chemical compounds have been found in marine species (Stolton, 2010a). Animals are also used as models on which to test potentially useful drugs or techniques (Gaston and Spicer, 2004), though such practices may be morally questionable.
Despite advances in computer-assisted drug design, molecular biology and gene therapy, there remains a pressing need for new drugs and biological materials will continue to play a major role (Amirkia and Heinrich, 2014; Gaston and Spicer, 2004; Nair et al, 2011). For example, one in every 125 plant species studied has produced a major drug, while for synthesised chemicals, the potential for finding major new drugs is of the order of one in 10 000 compounds tested (Dobson, 1995; Gaston and Spicer, 2004).
Just as with food above, the proportion of species that have been investigated for potential derivation of drugs is quite small (Lall and Kishore, 2014; Stolton, 2010a). For example, as of 1995, whilst about 37 500 species of plants had been studied photochemically, only about 14 000 had been studied for at least one type of biological activity (Sukara, 2014; Verpoorte,
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1998). This shows that there is still vast potential for deriving more drugs from biodiversity.
The medicinal value of plants and animals, both current and future, therefore provides a powerful argument for their conservation, just as with their value as a source of food for people.
Industrial materials: Biological diversity also has immense industrial value (Belk and Borden, 2008; Guittonny-Philippe et al, 2014; Kunin and Lawton, 1996; Kurian et al, 2013;
Quirósa et al, 2014; Sandava et al, 2011; Tofalo et al, 2014), with a wide range of industrial materials, or templates for their production, being derived directly from biological resources (Gaston and Spicer, 2004; Pegoretti et al, 2014). These include building materials, fibres, dyes, resins, gums, adhesives, rubber, oils and waxes, and perfumes (Kunin and Lawton, 1996; Pegoretti et al, 2014). Many agricultural chemicals including herbicides, fungicides and insecticides are also derived from natural products, or synthesised using natural chemicals as templates (Kunin and Lawton, 1996).
Biological materials have provided the models (biomimicry) for many industrial materials and structures (Gaston and Spicer, 2004). For example, inspiration for the dome of the Crystal Palace in London came from the Amazonian water lily victoria amazonica, air conditioning systems from the mounts constructed by termites, the echo-sounder from bats, and infrared sensors from the thermosensitive pit organ of the rattle snake (Gaston and Spicer, 2004; Kunin and Lawton, 1996). As is the case with food and medicine, the scope for exploitation of a far greater diversity of organisms for industrial materials is vast, and for that reason, biological resources cannot be allowed to go into extinction. However, it is important to note that most of the industrial uses of biodiversity have also immensely contributed to the degradation of the earth’s biological resources.
Ecotourism: Ecotourism is by definition tourism founded on biodiversity, and has developed into a massive industry (Bayliss et al, 2014; Borgerhoff Mulder and Coppolillo, 2005;
Leisher et al, 2010; Tyrväinen et al, 2014). Donohoe and Needham (2006: 192) note that
“ecotourism has consistently grown and is now widely considered the fastest growing sub- component of the world’s largest industry - tourism”. According to Fillion et al (1994), an estimated 157-236 million people took part in international ecotourism in 1988, while in 1998, an estimated 9 million people went for whale watching alone, with expenditure on just this activity totalling US$1 billion (Hoyt, 2000; Weaver and Lawton, 2007). According to the UN World Tourism Organisation (UNWTO, 2014), international tourist arrivals grew by an
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estimated 5% in 2013 (above the long-term forecast of 3.8% per year between 2010 and 2020), reaching a record 1 087 million despite sluggish global economic growth and numerous geopolitical challenges. The UNWTO (2014) further notes that international tourism receipts generated a total of US$1 079 billion (Euro 840 billion) in 2012.
The arguments for conserving biodiversity based on utility are, however, limited. The major weakness with a conservation system wholly based on economic motives is that most members of the biological community do not have economic value (Doak et al, 2014).
Conservationists often fall into the trap of justifying species preservation for utilitarian purposes, thereby sanctioning the humanistic attitude that is responsible for the biodiversity crisis (Maynard et al, 2014; Noss and Cooperrider, 1994). The attitude implied by economic valuations of biodiversity is that the worth of a species depends on its direct utility to humans, and if a species is of no benefit to them, then it is worthless (Braat and de Groot, 2012; Noss and Cooperrider, 1994). This predisposes species to extinction.
At best, the utilitarian argument for biodiversity conservation is a double-edged sword (Noss and Cooperrider, 1994). Under certain circumstances, it might help gain public support for protecting species and ecosystems, while in other cases it can be used to justify the destruction or neglect of seemingly worthless life forms (Noss and Cooperrider, 1994). In both cases, it encourages disrespect for species in and of themselves (Braat and de Groot, 2012; Maynard et al, 2014; Noss and Cooperrider, 1994). It is also quite disturbing to note that current arguments for maintaining international biodiversity, such as those expressed in the Global Biodiversity Strategy, are thoroughly utilitarian, hanging almost entirely on presumed benefits of biodiversity to humans (Doak et al, 2014; Holden et al, 2014; Noss and Cooperrider, 1994; WRI/ IUCN/ UNEP, 1992). The sustainable development theme of the Global Biodiversity Strategy, and related international conservation programmes, is thus potentially dangerous for the survival of biodiversity if strict protection to sensitive areas is not part of the programme (Holden et al, 2014; Noss and Cooperrider, 1994; Robinson, 1993).