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Extinction è un film statunitense del 2018, del genere fantascienza e thriller, diretto da Ben Young su sceneggiatura di Spenser Cohen, Eric Heisserer e Brad Kane. Trama. Peter è un ingegnere con incubi ricorrenti in cui lui e la sua famiglia soffrono a causa di violenti scontri con un nemico extraterrestre.
- Extinction
- inglese
Extinction is the termination of a taxon by the death of its last member. A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively.
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27 giu 2018 · Regia di Ben Young . Un film con Lizzy Caplan, Michael Peña, Emma Booth, Mike Colter, Tom Riley . Cast completo Titolo originale: Extinction . Genere Fantascienza, Thriller - USA , 2018 , Consigli per la visione di bambini e ragazzi: +13. Condividi. Ultimo aggiornamento mercoledì 27 giugno 2018.
- Ben Young
- Lizzy Caplan
19 ott 2023 · extinction. noun. process of complete disappearance of a species from Earth. fossil. noun. remnant, impression, or trace of an ancient organism. Jurassic. adjective. having to do with the time period between 190 million and 140 million years ago, characterized by an abundance of dinosaurs and ammonites.
- Overview
- Mass extinctions
- Human-induced extinctions
Extinction refers to the dying out or extermination of a species. Extinction occurs when species are diminished because of environmental forces such as habitat fragmentation, climate change, natural disaster, overexploitation by humans, and pollution, or because of evolutionary changes in their members (genetic inbreeding, poor reproduction, decline in population numbers).
Are mass extinctions common?
Mass extinctions are unusual because of the large numbers of taxa that die out, the concentrated time frame, the wide geographic area affected, and the many different kinds of animals and plants eliminated. The fossil record shows evidence of five mass extinction events, the first being the Ordovician-Silurian extinction (about 443 million years ago). Some scientists argue that we are currently experiencing a sixth mass extinction.
How do humans cause extinctions?
Many species have become extinct because of human activities such as hunting, overharvesting, the conversion of natural ecosystems to cropland and urban areas, pollution, and other alternations or destruction of natural environments. The current rates of human-induced extinctions are estimated to be about 1,000 to 10,000 times greater than past natural (background) rates of extinction.
extinction, in biology, the dying out or extermination of a species. Extinction occurs when species are diminished because of environmental forces (habitat fragmentation, global change, natural disaster, overexploitation of species for human use) or because of evolutionary changes in their members (genetic inbreeding, poor reproduction, decline in population numbers).
Although extinction is an ongoing feature of Earth’s flora and fauna (the vast majority of species ever to have lived are extinct), the fossil record reveals five unusually large extinctions, called mass extinction events, each involving the demise of vast numbers of species. These conspicuous declines in diversity are referred to as mass extinctions; they are distinguished from the majority of extinctions, which occur continually and are referred to as background extinction. Ranked in descending order of severity, they are:
1.Permian extinction (about 265.1 million to about 251.9 million years ago), the most dramatic die-off, eliminating about half of all families and about 90 percent of all species, which included some 95 percent of marine species (nearly wiping out brachiopods and corals) and about 70 percent of land species (including plants, insects, and vertebrates).
2.Ordovician-Silurian extinction (about 443.8 million years ago), which included about 25 percent of marine families and 85 percent of marine species.
3.Cretaceous-Tertiary (K-T), or Cretaceous-Paleogene (K-Pg), extinction (about 66.0 million years ago), involving about 80 percent of all animal species, including the dinosaurs and many species of plants. Although many scientists contend that this event was caused by one or more large comets or asteroids striking Earth, others maintain that it was caused by climatic changes associated with the substantial volcanic activity of the time.
4.End-Triassic extinction (about 201.3 million years ago), possibly caused by rapid climate change or by an asteroid striking Earth. This mass extinction event caused about 20 percent of marine families and some 76 percent of all extant species to die out, possibly within a span of about 10,000 years, thus opening up numerous ecological niches into which the dinosaurs evolved.
5.Devonian extinctions (407.6 million to about 358.9 million years ago), which included 15–20 percent of marine families and 70–80 percent of all animal species. Roughly 86 percent of marine brachiopod species perished, along with many corals, conodonts, and trilobites.
Many species have become extinct because of hunting and overharvesting, the conversion of wetlands and forests to croplands and urban areas, pollution, the introduction of invasive species, and other forms of human-caused destruction of their natural environments. Indeed, current rates of human-induced extinctions are estimated to be about 1,000 times greater than past natural (background) rates of extinction, leading some scientists to call modern times the sixth mass extinction. This high extinction rate is largely due to the exponential growth in human numbers: growing from about 1 billion in 1850, the world’s population reached 2 billion in 1930 and more than 7.8 billion in 2020 and is expected to reach about 10 billion by 2050. As a result of increasing human populations, habitat loss is the greatest factor in current levels of extinction. For example, less than one-sixth of the land area of Europe has remained unmodified by human activity, and more than half of all wildlife habitat has been eliminated in more than four-fifths of countries in the paleotropics (the Old World tropics that span Africa, Asia, and Indonesia). By 2020 several ecological studies had reported dramatic decreases in wildlife populations worldwide and increases in the numbers of threatened and endangered species, especially among terrestrial mammals and vertebrates.
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In addition, increased levels of greenhouse gases have begun to alter the world’s climate, with slowly increasing surface temperatures expected by the middle of the 21st century to force many species to migrate toward the poles and up mountain slopes in order to remain in habitats with the same climate conditions. Most ecologists, conservation biologists, and climate scientists worry that global warming will contribute greatly to species extinctions. For example, one study released in 2015 that examined 130 extinction models from previous studies predicted that 5.2 percent of species would be lost as a result of global warming alone with a rise in average temperatures of 2 °C (3.6 °F) above temperature benchmarks taken before the start of the Industrial Revolution. The study also predicted that about 16 percent of Earth’s species would be lost if surface warming increased to about 4.3 °C (7.7 °F). Changes in ocean temperatures and increasing ocean acidification also threaten many marine species, especially corals and mollusks with external shells.
Overexploitation from hunting and harvesting also has adversely affected many species. For example, about 20 million tropical fish and 12 million corals are harvested annually for the aquarium trade, depleting natural populations in some parts of the world.
All these factors have increased the numbers of threatened species. Almost one in four mammal species, including four of the six remaining species of great apes, and one in eight bird species were considered at significant risk of extinction at the start of the 21st century. In addition, the World Wildlife Fund noted in a 2016 report that vertebrate populations overall declined by 58 percent between 1970 and 2010.
31 lug 2018 · Recensione Extinction: Michael Peña contro l’apocalisse aliena. La recensione di Extinction, il film Netflix che racconta una peculiare invasione aliena.
5 feb 2019 · Extinction happens when environmental factors or evolutionary problems cause a species to die out. The disappearance of species from Earth is ongoing, and rates have varied over time.
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