Species extinctions

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  • Even though human-induced species extinction presently seems to rank low on peoples’ attention scale compared to other political and societal topics, this does not mean that its significance in earth history or its ecological consequences have diminished in any way. It must repeatedly be made clear that if current trends continue, within the next one hundred years half of all our planet’s species will most likely have become extinct.

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  • Biological invasions are one of the major threats to our native biodiversity. The magnitude of biodiversity losses, land degradation and productivity losses of managed and natural ecosystems due to invasive species is enormous. It has an adverse impact on our efforts to maintain biodiversity and on our conservation programs, and thus could create societal instability.

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  • Global warming is the rising average temperature of Earth's atmosphere and oceans since the late 19th century and its projected continuation. Since the early 20th century, Earth's average surface temperature has increased by about 0.8 °C, with about two thirds of the increase occurring since 1980. Warming of the climate system is unequivocal, and scientists are more than 90% certain that most of it is caused by increasing concentrations of greenhouse gases produced by human activities such as deforestation and the burning of fossil fuels.

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  • Information about climate1 is used to make decisions every day. From farmers deciding which crops to plant next season to mayors in large cities deciding how to prepare for future heat waves, and from an insurance company assessing future flood risks to a national security planner assessing future conflict risks from the impacts of drought, users of climate information span a vast array of sectors in both the public and private spheres. Each of these communities has different needs for climate data, with different time horizons (see Box 1) and different tolerances for uncertainty...

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  • Conserving Living Natural Resources provides students, managers, and general readers with an introduction to the principles of managing biological resources. It presents the historical and conceptual contexts of three seminal approaches to the management of living natural resources: utilitarian management for harvest of featured species and control of unwanted species, protection and restoration of populations and habitats to maintain biodiversity, and management of complex ecosystems to sustain both productivity and biodiversity.

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  • Part memoir, nutritional primer, and political manifesto, this controversial examination exposes the destructive history of agriculture—causing the devastation of prairies and forests, driving countless species extinct, altering the climate, and destroying the topsoil—and asserts that, in order to save the planet, food must come from within living communities. In order for this to happen, the argument champions eating locally and sustainably and encourages those with the resources to grow their own food.

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  • Against this previously explained background of European developments and full adoption in Spain, different initiatives were started in several university and professional sectors of the country to study the existing situation, aiming at building knowledge that will permit undertaking the reform in the best possible way. Some of these initiatives refer specifi cally to ‘Business Administration’ studies. We refer to them in this section. In the next section we will review the specifi c actions already underway in Spanish Universities. ...

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  • Chapter 15 - Natural resource and energy economics. After studying this chapter you will be able to understand: Explain why falling birthrates mean that we are not likely to run out of natural resources, describe why using a mix of energy sources is efficient, even if some of them are quite costly, discuss why running out of oil would not mean running out of energy, show how the profit motive can encourage resource conservation, relate how to use property rights to prevent deforestation and species extinction.

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  • Chapter 15 - Natural resource and energy economics. After studying this chapter you will be able to understand: Explain why falling birthrates mean that we are not likely to run out of natural resources, describe why using a mix of energy sources is efficient, even if some of them are quite costly, discuss why running out of oil would not mean running out of energy, show how the profit motive can encourage resource conservation, relate how to use property rights to prevent deforestation and species extinction.

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  • Đọc đoạn văn sau và trả lời các câu hỏi: Since the world has become industrialized, there has been an increase in the number of animal species that have either become extinct or have neared extinction. Bengal tigers, for instance, which once roamed the jungles in vast numbers, now number only about 2,300, and by 5 the year 2025 their population is estimated to be down to zero. What is alarming about the case of the Bengal tiger is that this extinction will have been caused almost entirely by poachers who, according to some sources, are not interested in material...

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  • Life on Earth originated and then evolved from a universal common ancestor approximately 3.7 billion years ago. Repeated speciation and the divergence of life can be inferred from shared sets of biochemical and morphological traits, or by shared DNA sequences. These homologous traits and sequences are more similar among species that share a more recent common ancestor, and can be used to reconstruct evolutionary histories, using both existing species and the fossil record. Existing patterns of biodiversity have been shaped both by speciation and by extinction....

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  • The relationship between the manufacturers of electronic components and the assemblers of electronic circuitry resembles that between two different orders of living beings, for example insects and plants: they need one another to be able to exist, and for that reason there are close links between the evolutionary paths of both. The shapes and the dimensions of their bodies, or respectively their functions, must match one another, so that whatever is needed to ensure the survival of either species can be properly performed. Any mistakes or mismatches are punished by extinction....

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  • Insect :côn trùng Tortoise : rùa Trang 107 Extinct (adj) : tuyệt chủng Extinction (n) : sự tuyệt chủng Endangered species : các loài có nguy cơ tuyệt chủng

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  • Chapter 15 Ecological Applications at the Level of Population Interactions: Pest Control and Harvest Management 15.1 Introduction Humans are very much a part of all ecosystems. Our activities sometimes motivate us to drive towards extinction the species we identify as pests, to kill individuals of species we harvest for food or fiber while ensuring the persistence of their populations.

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  • By playing a role in the near-annihilation of a species, Theodore Roosevelt, the president of the United States at the turn of the twentieth century, unwittingly laid the groundwork for the most dramatic triumph yet in the use of artificial insemination (AI) to rescue a species from extinction. In the early 1900s, waves of immigrants from Europe settled in the American Midwest. As humans transformed the land, they declared war on a perceived pest: the prairie dog.

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  • Book summary Ulysses arrived on Planet Earth with an invisible space ship after light years of travel. He came from Planet Progress. It was only during the last two generations that the people of Planet Progress actually secured the survival of the human species on their planet. They came very close to self-extinction...... For over a century Planet Earth has been under observation by the scientists of Planet Progress. These scientists were amazed to discover the great similarities between the two planets.

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  • Even as new species are evolving, however, others may become extinct. The rate at which species become extinct may be low in one lineage and high in another. It’s also possible for the rate of extinction to rise, only to drop again later. All of these processes can also unfold at the same time, and so the range of possible long-term patterns in evolution can be enormous. A lineage with a low rate of speciation may end up enormously diverse because its rate of extinction is even lower.

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  • Understanding the long-term patterns of speciation and extinction may help sci- entists answer some of the biggest questions about today’s patterns of bio diver- sity—such as why the tropics are so diverse. David Jablonski, a paleontologist at the University of Chicago, has tackled the question by analyzing the fossil record of bivalves, noting where they were located, how large their ranges became, and how long they endured. Jablonski’s analysis of 3,599 species from the past 11 million years revealed a striking pattern.

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  • This book is about the conservation of genetic diversity of wild plants in situ in their natural surroundings, primarily in existing protected areas but also outside conventional protected areas. A lot of effort has been dedicated to conserving plant biodiversity, but most of this has focused on rare plant communities or individual species threatened with extinction.

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  • Chapter 9 Population Viability Analysis: Data Requirements and Essential Analyses The biological diversity of the earth is threatened by the burgeoning human population. To prevent extinctions of species, conservationists must manage many populations in isolated habitat parcels that are smaller than desirable.

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