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List Of Mammals Of Central America
This is a list of the native wild mammal species recorded in Central America. Central America is usually defined as the southernmost extension of North America; however, from a biological standpoint it is useful to view it as a separate region of the Americas. Central America is distinct from the remainder of North America in being a Tropics, tropical region, part of the Neotropical realm, whose flora and fauna display a strong South American influence. The rest of North America is mostly subtropical or Temperateness, temperate, belongs to the Nearctic realm, and has far fewer species of South American origin. At present Central America bridges North and South America, facilitating migrations in both directions, but this phenomenon is relatively recent from a geological perspective. The formation of this land bridge through volcanic activity three million years ago precipitated the Great American Interchange, an important biogeography, biogeographical event. In part because of thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conservation International
Conservation International (CI) is an American nonprofit environmental organization headquartered in Crystal City, Virginia, in Arlington County, Virginia. CI's work focuses on science, policy and partnership with businesses, governments and communities. The organization employs nearly 1,000 people and works with more than 2,000 partners in 29 countries. CI has helped support 1,200 protected areas and interventions across 77 countries, protecting more than 13 million square kilometers (5 million square miles) of land and sea. History Conservation International was founded in 1987 with the goal of protecting nature for the benefit of people. In 1989, CI formally committed to the protection of biodiversity hotspots, ultimately identifying 36 such hotspots around the world and contributing to their protection. The model of protecting hotspots became a key way for organizations to do conservation work. On July 1, 2017, Peter Seligmann stepped down as CEO of CI and a new executive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocene Extinction
The Holocene extinction, also referred to as the Anthropocene extinction or the sixth mass extinction, is an ongoing extinction event caused exclusively by human activities during the Holocene epoch. This extinction event spans numerous families of plants and animals, including mammals, birds, reptiles, amphibians, fish, and invertebrates, impacting both terrestrial and marine life, marine species. Widespread degradation of biodiversity hotspots such as coral reefs and rainforests has exacerbated the crisis. Many of these extinctions are undocumented, as the species are often undiscovered before their extinctions. Current extinction rates are estimated at 100 to 1,000 times higher than natural background extinction rates and are accelerating. Over the past 100–200 years, biodiversity loss has reached such alarming levels that some conservation biologists now believe humankind, human activities have triggered a mass extinction, or are on the cusp of doing so. As such, after the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem
An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and energy flows. Ecosystems are controlled by external and internal Environmental factor, factors. External factors—including climate—control the ecosystem's structure, but are not influenced by it. By contrast, internal factors control and are controlled by ecosystem processes; these include decomposition, the types of species present, root competition, shading, disturbance, and succession. While external factors generally determine which Resource (biology), resource inputs an ecosystem has, their availability within the ecosystem is controlled by internal factors. Ecosystems are wikt:dynamic, dynamic, subject to periodic disturbances and always in the process of recovering from past disturbances. The tendency of an ecosystem to remain clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Warming
Present-day climate change includes both global warming—the ongoing increase in global average temperature—and its wider effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global temperatures is driven by human activities, especially fossil fuel burning since the Industrial Revolution. Fossil fuel use, deforestation, and some agricultural and industrial practices release greenhouse gases. These gases absorb some of the heat that the Earth radiates after it warms from sunlight, warming the lower atmosphere. Carbon dioxide, the primary gas driving global warming, has increased in concentration by about 50% since the pre-industrial era to levels not seen for millions of years. Climate change has an increasingly large impact on the environment. Deserts are expanding, while heat waves and wildfires are becoming more common. Amplified warming in the Arctic has c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene Megafauna
The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, typically defined as animal species having body masses over , which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by their extreme size bias towards large animals (with small animals being largely unaffected), and widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence. The timing and severity of the extinctions varied by region and are generally thought to have been driven by humans, climatic change, or a combination of both. Human impact on megafauna populations is thought to have been driven by hunting ("overkill"), as well as possibly environmental alteration. The relative importance of human vs climatic factors in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoindians
Paleo-Indians were the first peoples who entered and subsequently inhabited the Americas towards the end of the Late Pleistocene period. The prefix ''paleo-'' comes from . The term ''Paleo-Indians'' applies specifically to the lithic period in the Western Hemisphere and is distinct from the term ''Paleolithic''.''Paleolithic'' specifically refers to the period between million years ago and the end of the Pleistocene in the Eastern Hemisphere. It is not used in New World archaeology. Traditional theories suggest that big-animal hunters crossed the Bering Strait from North Asia into the Americas over a land bridge (Beringia). This bridge existed from 45,000 to 12,000 BCE (47,000–14,000 BP). Small isolated groups of hunter-gatherers migrated alongside herds of large herbivores far into Alaska. From BCE ( BP), ice-free corridors developed along the Pacific coast and valleys of North America. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Before Present
Before Present (BP) or "years before present (YBP)" is a time scale used mainly in archaeology, geology, and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the "present" time changes, standard practice is to use 1January 1950 as the commencement date (epoch) of the age scale, with 1950 being labelled as the "standard year". The abbreviation "BP" has been interpreted retrospectively as "Before Physics", which refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, which scientists must account for when using radiocarbon dating for dates of origin that may fall after this year. In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation "RCYBP" stands for the explicit "radio carbon years before present". Usage The BP scale is s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Extinction Event
The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, typically defined as animal species having body masses over , which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by their extreme size bias towards large animals (with small animals being largely unaffected), and widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence. The timing and severity of the extinctions varied by region and are generally thought to have been driven by humans, climatic change, or a combination of both. Human impact on megafauna populations is thought to have been driven by hunting ("overkill"), as well as possibly environmental alteration. The relative importance of human vs climatic factors in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caribbean Sea
The Caribbean Sea is a sea of the Atlantic Ocean, North Atlantic Ocean in the tropics of the Western Hemisphere, located south of the Gulf of Mexico and southwest of the Sargasso Sea. It is bounded by the Greater Antilles to the north from Cuba to Puerto Rico, the Lesser Antilles to the east from the Virgin Islands to Trinidad and Tobago, South America to the south from the Venezuela, Venezuelan coastline to the Colombia, Colombian coastline, and Central America and the Yucatán Peninsula to the west from Panama to Mexico. The Geopolitics, geopolitical region around the Caribbean Sea, including the numerous islands of the West Indies and adjacent coastal areas in the mainland of the Americas, is known as the Caribbean. The Caribbean Sea is one of the largest seas on Earth and has an area of about . The sea's deepest point is the Cayman Trough, between the Cayman Islands and Jamaica, at below sea level. The Caribbean coastline has many gulfs and bays: the Gulf of Gonâve, the Gul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the continents of Asia and Australia in the west and the Americas in the east. At in area (as defined with a southern Antarctic border), the Pacific Ocean is the largest division of the World Ocean and the hydrosphere and covers approximately 46% of Earth's water surface and about 32% of the planet's total surface area, larger than its entire land area ().Pacific Ocean . ''Encyclopædia Britannica, Britannica Concise.'' 2008: Encyclopædia Britannica, Inc. The centers of both the Land and water hemispheres, water hemisphere and the Western Hemisphere, as well as the Pole of inaccessi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lowland
Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of a plain that are conditionally categorized by their elevation above the sea level. Lowlands are usually no higher than , while uplands are somewhere around to . On unusual occasions, certain lowlands such as the Caspian Depression lie below sea level. Uplands areas tend to spike into valleys and mountains, forming mountain ranges while lowland areas tend to be uniformly flat, although both can vary such as the Mongolian Plateau. Upland habitats are cold, clear and rocky whose rivers are fast-flowing in mountainous areas; lowland habitats are warm with slow-flowing rivers found in relatively flat lowland areas, with water that is frequently colored by sediment and organic matter. These classifications overlap with the geological definitions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
