EVR HW 8 (Exam 3)

25 July 2022
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A population of birds is found on a remote island. Which of the following information is most important in deciding if the birds all belong to a single species?
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Whether the matings produce viable eggs or offspring of some matings are sterile.
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Of the following, ________ can change local species diversity but not global species diversity.
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immigration and extirpation
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Of the following, ________ can change global species diversity.
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specifation and extinction
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Which regions of the world tend to have the greatest species richness?
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regions near the equator
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__________ provides the raw material for adaptation to local conditions.
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genetic diversity
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Species richness is the __________.
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number of species in an area
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Biodiversity is the diversity of life at what level(s) of biological organization?
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genetic, species, and ecosystem levels
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Global biodiversity exists in a number of patterns. The largest and most obvious of these is that biodiversity is __________.
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greatest at the equator and drops as you move farther north or south
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Why can many different species coexist and thrive in areas close to the equator?
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Stable equatorial climatic conditions discourage any one species from dominating the ecosystem and encourage biodiversity.
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Biodiversity enhances human food security because it ________.
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is a potential source of new food items or new genetic varieties of existing foods
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Removal of ________ will always result in the greatest changes in an ecological system
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a keystone species
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Ecotourism ________.
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increases biodiversity by providing income to areas that might otherwise be destroyed
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__________ is the gradual piecemeal degradation of an area by such activities as logging and road building.
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Habitat fragmentation
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__________ is the term we use when a population disappears from a given area but not globally.
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Extirpation
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Which of the following is an example of the single greatest cause of species extinction?
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habitat fragmentation caused by building a road through a forest
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When a species declines in number, it also __________.
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occupies less area than it once did
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Which of the following types of species would be most vulnerable to overharvesting by people?
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whales
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The IUCN's Red List is
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an updated list of species facing unusually high risk of extinction
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Paleontologists and ecologists agree that ________.
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99% of all species that have ever existed are now extinct
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__________ provide(s) a benefit to humans free of charge.
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ecosystem services
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Which one of the following is an ecosystem service?
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purification of water
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The development of pharmaceutical products has been __________.
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aided by protection of ecosystem diversity
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Pharmaceuticals produced from wild species generate up to $150 billion in sales and save many lives each year. This is an example of __________.
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ecosystem services
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More greenhouse gas emissions will indirectly lead to ________.
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loss of ecosystem services
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Loss of aesthetic and spiritual ties with nature would be less if we ________.
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decreased the rate of habitat alteration and destruction
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Changes in habitat have tremendous effects on the organisms that depend on them. These effects are ________.
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generally negative; organisms are already adapted to the habitats in which they occur and any change is likely to render the habitat less suitable
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The greatest cause of the worldwide loss of species is ________.
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Habitat destruction
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What is the greatest contributing factor in the loss of polar bears in arctic areas?
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decline in sea ice
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Wildlife in the Serengeti is currently threatened by ________.
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plans to build a highway that passes through the park
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A species of lizard has gone extinct. This could be due to any of the following reasons except ________.
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increased genetic diversity within the species
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In general, successfully introduced non-native species experience ________.
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competitive success against native species
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Bullfrog tadpoles are often sold as fish bait, even in areas where they do not occur naturally. When people buy 10 of them and don't use them all, they often dump the remainder into the lake or river. This is an example of ________.
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introduced species
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The species most often vulnerable to human impact is the ________.
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top predator
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A migratory bat species pollinates agave plants in northern Mexico on its way to the southwestern United States where it spends the summer eating insects and reproducing. Farmers spraying pesticides affect these bats, which eat the insects and also feed them to the baby bats. This could be the start of a story about ________.
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threats to a keystone species
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European rabbits were introduced into Australia and quickly spread, reproduced, and became a terrible pest. They eat up to $600 million worth of food and pasture crops annually, and have damaged the populations of many native plants and the populations of animals that eat the plants. Twice in the past 50 years, rabbit diseases have been introduced to try to control the population, with some success. This is a case where ________.
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an invasive species has reduced the genetic diversity of indigenous species
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The country of Belize depends on lobster for a major portion of its income, along with fishing and tourism. Over the past 30 years the average size of an individual lobster has dropped, even as increasing numbers of Belizeans buy boats, build lobster traps, and enter the industry. This is an example of ________.
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overharvesting
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The wood thrush makes its nest in woodlands in the northern and eastern United States. As patches of woods become smaller, increasing numbers of wood thrush nests have eggs laid in them by the brown-headed cowbird. Cowbirds live in open fields and are nest parasites; the female cowbird flies up to an unattended nest, quickly lays an egg in another bird's nest, and leaves the host parents to raise their "adopted" young. Wood thrushes are decreasing in numbers because ________.
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habitat fragmentation makes it easier for cowbird parasitism to occur
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Being interested in native butterflies, you include the native caterpillar host plants of several butterflies in your annual landscape design. You are happy to see that caterpillars and butterflies appear in your yard. However, the butterflies tend to disperse out of our yard. To keep the butterflies in your garden, an urban wildlife specialist suggests you ________.
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introduce native flowering plants the adult butterflies need for nectar, their main food
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In addition to the butterfly project, you decide to stop spraying the pesticides that control lawn pests. Over the next year, you notice that the lawn grass doesn't grow as well, but many other species of plants invade the lawn, many of them native species. This will result in all of the following, except ________.
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Lower survival rates for the caterpillars and butterflies
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From your experiences with the lawn and the butterfly garden, you can affirm that ________.
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native plants are more likely to support local herbivorous animals than are exotic plant species
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You also decide to greatly reduce the amount of chemical fertilizers you use in your landscape and rely more on mulching and composting. This will benefit your yard "ecosystem" by ________.
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reducing nutrient pollution in nearby areas and increasing soil organisms' biodiversity
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The primary legislation for protecting biodiversity in the United States is the __________.
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endangered species act
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Conservation biology is different from other fields of science discussed in the book because __________.
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it is an applied and goal-oriented science, with implicit values and ethical standards
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How is community-based conservation different from more traditional approaches to conservation?
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In community-based conservation, local people are involved with protecting the habitat of endangered species, allowing them to still gain benefit from its resources.
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Which of the following best describes an umbrella species?
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a species whose protection will result in the protection of a large number of species that require the same habitat
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Which of the following statements about cloning organisms is true?
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Producing cloned animals and keeping them in zoos does not increase biodiversity of the species.
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Which of the following regions of the world is the driving force behind the consumption of rhino horn? You are employed by the federal agency in charge of working to control the illegal trade of animals and their parts. Whom do you work for? Which of the following is true regarding the belief that rhino horn is valuable for medicinal purposes? What is the main argument against legalizing the trade in rhino horn? You are a big-game hunter, and you wish to legally take down a rhino. Where should you go? Which of the following is true?
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Asia Fish and wildlife services the age of the horn does not matter demand for horn would quickly outstrip supply South Africa Black rhinos are more critically endangered than white rhinos.
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If a conservation biologist wanted to try to stop the largest cause of species extinction, what should he or she focus on?
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habitat destruction
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Overall, how many studies showed a positive effect of organic farming on biodiversity? What percentage of the studies showed a negative effect of organic farming on organisms? For which group of organisms is evidence of positive effects the strongest? What is the overall ratio of positive effects of organic farming to negative effects? A scientist plans to further investigate the impact of organic farming on biodiversity. Which groups of organisms should the scientist select?
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66 11% plants 8:25:1 Beetles and other arthropods
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What percent of the plant species found on Madagascar are unique to that island? The human population of Madagascar doubles about every _____ years. What is a lemur? Much of the original forest cover on Madagascar has been destroyed primarily as a result of _____. What is the cause of the red color of the waters about Madagascar?
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80 25 a primate only found on Madagascar burning for agricultural purposes soil that has washed into the ocean
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What is the second greatest cause of decline for threatened species? Which of these statements is supported by the graph? Select all that apply.
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pollution ?
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One of the most severe consequences of habitat degradation is the _____ of a population. A sink habitat is where a subpopulation's death rate is _____. Fertilizer runoff can result in _____ a lake. Most biodiversity hot spots are in the _____. _____ is the increase in pesticide concentration as the pesticides pass up a food chain.
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fragmentation greater than its reproductive rate the eutrophication of tropics Biological magnification
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According to island biogeography, what is the relationship between an island's distance from the mainland and the number of species present on the island? Why is a new island more hospitable to colonizers than an older island is? What is the relationship between colonizing success and the number of species already established on an island? The number of species on an island remains relatively constant when _____.
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The farther an island is from the mainland, the fewer the number of species found on the island. The intensity of both competition and predation is less on the newer island. As the number of established species on an island increases, colonizing success decreases. the rate of successful colonization equals the extinction rate