Loss of Resources

The Lost River and shortnose suckers were once numerous enough to support a fishing and canning industry on the shores of Upper Klamath Lake. Even before the arrival of European settlers, the native people of the area relied heavily upon these fish, which are referred to as "c'wam" and "qapdo" in the Klamath language, as a mainstay of their diet. The loss of these species represents a tremendous impoverishment of wild food sources. The list of species that are harvested directly from natural areas is large and diverse—for example, wood for fuel, shellfish for protein, plants for local medicines, and flowers for perfume. The loss of any of these species affects human populations economically— one estimate places the economic value of wild species in the United States at $87 billion a year, or about 4% of the gross domestic product. Some of the thousands of valuable species known to humans are described in Chapter 3.

Wild relatives of plants and animals that have been domesticated by humans (such as agricultural crops and cattle) are also valuable resources for humans (Figure 14.8). Genes and gene variants that have been "bred out" of domesticated species are often still found in their wild relatives. These genetic resources represent a reservoir of traits that could be reintroduced into agricultural species by breeding or genetic engineering (see Chapter 7). Often, traits that seem unimportant in agricultural crops later prove to be useful, or in fact critical, to the species when it is exposed to new diseases or pests. Agricultural scientists who are attempting to produce better strains of wheat, rice,

Figure 14.8 Wild relatives of domesticated crops and animals. (a) Teosinte is the ancestor of modern corn, which was first cultivated in Central America. This species, Zea diploperennis, was discovered in a remote Mexican site in 1978. (b) An aurochs, the wild ancestor of modern cattle species, disappeared from its original range in Northern Europe in the 1500s. This modern aurochs was produced after many generations of cross-breeding domesticated cattle and is probably very similar to the extinct wild aurochs.

Figure 14.8 Wild relatives of domesticated crops and animals. (a) Teosinte is the ancestor of modern corn, which was first cultivated in Central America. This species, Zea diploperennis, was discovered in a remote Mexican site in 1978. (b) An aurochs, the wild ancestor of modern cattle species, disappeared from its original range in Northern Europe in the 1500s. This modern aurochs was produced after many generations of cross-breeding domesticated cattle and is probably very similar to the extinct wild aurochs.

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