Montane ecosystemsMontane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial factor in shaping plant community, biodiversity, metabolic processes and ecosystem dynamics for montane ecosystems. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall.
AustraliaAustralia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. Australia is the largest country by area in Oceania and the world's sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a megadiverse country, and its size gives it a wide variety of landscapes and climates, with deserts in the centre, tropical rainforests in the north-east, tropical savannas in the north, and mountain ranges in the south-east.
Great PlainsThe Great Plains (Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located just to the east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. It is the western part of the Interior Plains, which also include the mixed grass prairie, the tallgrass prairie between the Great Lakes and Appalachian Plateau, and the Taiga Plains and Boreal Plains ecozones in Northern Canada.
ArmeniaArmenia, officially the Republic of Armenia, is a landlocked country in the Armenian Highlands of West Asia, with geopolitical ties to Europe. It is a part of the Caucasus region and is bordered by Turkey to the west, Georgia to the north and Azerbaijan to the east, and Iran and the Azerbaijani exclave of Nakhchivan to the south. Yerevan is the capital, largest city and financial center. Armenia is a unitary, multi-party, democratic nation-state with an ancient cultural heritage.
Domestication of the horseHow and when horses became domesticated has been disputed. Although horses appeared in Paleolithic cave art as early as 30,000 BCE, these were wild horses and were probably hunted for meat. The clearest evidence of early use of the horse as a means of transport is from chariot burials dated c. 2000 BCE. However, an increasing amount of evidence began to support the hypothesis that horses were domesticated in the Eurasian Steppes in approximately 3500 BCE.
NomadA nomad is a member of a community without fixed habitation who regularly moves to and from areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the population of nomadic pastoral tribes slowly decreased, reaching an estimated 30–40 million nomads in the world . Nomadic hunting and gathering—following seasonally available wild plants and game—is by far the oldest human subsistence method.
Shortgrass prairieThe shortgrass prairie is an ecosystem located in the Great Plains of North America. The two most dominant grasses in the shortgrass prairie are blue grama (Bouteloua gracilis) and buffalograss (Bouteloua dactyloides), the two less dominant grasses in the prairie are greasegrass (Tridens flavus) and sideoats grama (Bouteloua curtipendula). The prairie was formerly maintained by grazing pressure of American bison, which is the keystone species.
HabitatIn ecology, habitat refers to the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity.
MeadowA meadow (ˈmɛdoʊ ) is an open habitat or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as these areas maintain an open character. Meadows can occur naturally under favourable conditions, but are often artificially created from cleared shrub or woodland for the production of hay, fodder, or livestock. Meadow habitats, as a group, are characterized as "semi-natural grasslands", meaning that they are largely composed of species native to the region, with only limited human intervention.
PampasThe Pampas (from the pampa, meaning "plain") are fertile South American low grasslands that cover more than and include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre Ríos, and Córdoba; all of Uruguay; and Brazil's southernmost state, Rio Grande do Sul. The vast plains are a natural region, interrupted only by the low Ventana and Tandil hills, near Bahía Blanca and Tandil (Argentina), with a height of and , respectively.
Canadian PrairiesThe Canadian Prairies (usually referred to as simply the Prairies in Canada) is a region in Western Canada. It includes the Canadian portion of the Great Plains and the Prairie Provinces, namely Alberta, Saskatchewan, and Manitoba. These provinces are partially covered by grasslands, plains, and lowlands, mostly in the southern regions. The northernmost reaches of the Canadian Prairies are less dense in population, marked by forests and more variable topography.
Hellenistic periodIn classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC to the death of Cleopatra VII (30 BC) followed by the emergence of the Roman Empire, as signified by the Battle of Actium in 31 BC and the conquest of Ptolemaic Egypt the following year. The Ancient Greek word Hellas (Ἑλλάς, Hellás) was gradually recognized as the name for Greece, from which the word Hellenistic was derived.