Megafauna in the context of "Quaternary extinction event"

The human history of the Americas is thought to begin with people migrating to these areas from Asia during the height of an ice age. These groups are generally believed to have been isolated from the people of the "Old World" until the coming of Europeans in 1492 with the voyages of Christopher Columbus.

The ancestors of today's American Indigenous peoples were the Paleo-Indians; they were hunter-gatherers who migrated into North America. The most popular theory asserts that migrants came to the Americas via Beringia, the land mass now covered by the ocean waters of the Bering Strait. Small lithic stage peoples followed megafauna like bison, mammoth (now extinct), and caribou, thus gaining the modern nickname "big-game hunters." Groups of people may also have traveled into North America on shelf or sheet ice along the northern Pacific coast.

It is believed that the peopling of the Americas began when Paleolithic hunter-gatherers (Paleo-Indians) entered North America from the North Asian Mammoth steppe via the Beringia land bridge, which had formed between northeastern Siberia and western Alaska due to the lowering of sea level during the Last Glacial Maximum (26,000 to 19,000 years ago). These populations expanded south of the Laurentide Ice Sheet, either by sea or land, and spread rapidly southward, occupying both North and South America no later than 14,000 years ago, and possibly before 20,000 years ago. The earliest populations in the Americas, before roughly 10,000 years ago, are known as Paleo-Indians. Indigenous peoples of the Americas have been linked to Siberian populations by proposed linguistic factors, the distribution of blood types, and in genetic composition as reflected by molecular data, such as DNA.

While there is general agreement that the Americas were first settled from Asia, the pattern of migration and the place(s) of origin in Eurasia of the peoples who migrated to the Americas remain unclear. The most generally accepted theory is that Ancient Beringians moved when sea levels were significantly lowered due to the Quaternary glaciation, following herds of now-extinct Pleistocene megafauna along ice-free corridors that stretched between the Laurentide and Cordilleran ice sheets. Another proposed route has them migrating down the Pacific coast to South America as far as Chile, either on foot or using boats. Any archaeological evidence of coastal occupation during the last Ice Age would now have been covered by the sea level rise, up to a hundred metres since then.

Magdalenian cultures (also Madelenian; French: Magdalénien) are later cultures of the Upper Paleolithic and Mesolithic in western Europe. They date from around 17,000 to 12,000 years before present. It is named after the type site of Abri de la Madeleine, a rock shelter (abri) located in the Vézère valley of Tursac in Dordogne, France.

Édouard Lartet and Henry Christy originally termed the period L'âge du renne "the age of the reindeer". They conducted the first archaeological excavation of the type site, publishing in 1875. The Magdalenian is associated with reindeer hunters. Magdalenian sites contain extensive evidence for the hunting of red deer, wild horses, and other megafauna present in Europe toward the end of the Last Glacial Period. The culture was geographically widespread, and later Magdalenian sites stretched from Portugal in the west to Poland in the east, and as far north as France, the Channel Islands, England, and Wales. Besides la Madeleine, the chief stations of the Magdalenian are Les Eyzies, Laugerie-Basse, and Gorges d'Enfer in the Dordogne; Grotte du Placard in Charente and others in Southwest France.

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 44 kg (97 lb), 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), the 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 extinctions has been the subject of long-running controversy, though some sources suggest that most scholars support at least a contributory role of humans in the extinctions.

Major extinctions occurred in Australia-New Guinea (Sahul) beginning around 50,000 years ago and in the Americas about 13,000 years ago, coinciding in time with the early human migrations into these regions. Extinctions in northern Eurasia were staggered over tens of thousands of years between 50,000 and 10,000 years ago, while extinctions in the Americas were virtually simultaneous, spanning only 3,000 years at most. Overall, during the Late Pleistocene about 65% of all megafaunal species worldwide became extinct, rising to 72% in North America, 83% in South America and 88% in Australia, with all mammals over 1,000 kg (2,200 lb) becoming extinct in Australia and the Americas, and around 80% globally. Africa, South Asia, and Southeast Asia experienced more moderate extinctions than other regions.

Several chronologies in the archaeology of the Americas include an Archaic Period or Archaic stage etc. It is often sub-divided, for example into "Early", "Middle" and "Late", or alternatively "Lower" and "Upper", stages. The dates, and the characteristics of the period called "Archaic" vary between different parts of the Americas. Sometimes also referred to as the "Pre-Ceramic stage" or period, it followed the Lithic stage and was superseded by the Formative stage, or a Preformative stage. The typical broad use of the terms is as follows:

• In Mesoamerican chronology the Archaic runs from about 3500 BC to 1800 BC; sites include Coxcatlan Cave, Tehuacán, showing the development of maize.
• In the periodization of pre-Columbian Peru the term may not be used, replaced by the Pre-Ceramic.
• In the Caribbean islands, the Archaic Age ranges from 6000 BC and 500 BC, when the earliest human settlements were established. These early settlers came from Central or South America.
• In the North American chronology the North American Archaic period runs from around 11,500 to 3200 cal yr B.P. and is usually subdivided into three subperiods: Early Archaic (11,500-8900 cal yr B.P.), Middle Archaic (8900-5800 cal yr B.P.), and Late Archaic (5800-3200 cal yr B.P.).

Cultures of the Archaic Stage are at some point in the development of the technologies of pottery, weaving, and developed food production; normally they are becoming reliant on agriculture, unless reliant on seafood. Social organization is developing into permanent villages. In the early parts of the period, hunting is gradually replaced by gathering, as the megafauna hunted in the Lithic stage decline. By the end of the Archaic, in parts of South America, there is "a stable agricultural system utilized by people living in permanent villages with ceremonial architecture".

Charismatic megafauna are animal species that are large—relative to the category that they represent—with symbolic value or widespread popular appeal, and are often used by environmental activists to gain public support for environmentalist goals. In this definition, animals such as penguins or bald eagles are megafauna because they are among the largest animals within the local animal community, and they disproportionately affect their environment. The vast majority of charismatic megafauna species are threatened and endangered by issues such as overhunting, poaching, black market trade, climate change, habitat destruction, and invasive species. In a 2018 study, the top twenty most charismatic megafauna (first to last) are the tiger, lion, elephant, giraffe, leopard, panda, cheetah, polar bear, wolf, gorilla, chimpanzee, zebra, hippopotamus, great white shark, crocodile, dolphin, rhinoceros, brown bear, koala, and blue whale.

Monte Verde is a Paleolithic archaeological site in the Llanquihue Province in southern Chile, located near Puerto Montt, Los Lagos Region. The site is primarily known for Monte Verde II, dating to approximately 14,550–14,500 calibrated years Before Present (BP). The Monte Verde II site has been considered key evidence showing that the human settlement of the Americas pre-dates the Clovis culture by at least 1,000 years. This contradicts the previously accepted "Clovis first" model which holds that settlement of the Americas began after 13,500 cal BP. The Monte Verde findings were initially dismissed by most of the scientific community, but the evidence then became more accepted in archaeological circles. The site also contains an older, much more controversial layer (Monte Verde I) suggested to date to 18,500 cal BP (16,500 BC), that lacks the general acceptance of Monte Verde II.

Monte Verde II represents a campsite with wooden tent-like structures that was later covered by a bog, sealing the site under a layer of anaerobic peat. The occupants of the site made rope and utilized animal skins, and consumed a variety of plant foods, including seaweed (despite the site being 60 kilometres (37 mi) from the ocean at the time), tubers, seeds, fruits and nuts. Remains at the site show that the occupants also butchered now extinct megafauna, including the gomphothere (elephant-relative) Notiomastodon and the llama Palaeolama.

Xenarthra (/zɛˈnɑːrθrə/; from Ancient Greek ξένος (xénos), meaning "strange, foreign", and ἄρθρον (árthron), meaning "joint") is a superorder and major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos. Extinct xenarthrans include the glyptodonts, pampatheres and ground sloths, with some glyptodonts and ground sloths reaching sizes of several tonnes, much larger than any living xenarthran. Xenarthrans originated in South America during the late Paleocene about 60 million years ago. They evolved and diversified extensively in South America during the continent's long period of isolation in the early to mid Cenozoic Era. They spread to the Antilles by the early Miocene and, starting about 3 million years ago, spread to Central and North America as part of the Great American Interchange. Nearly all of the formerly abundant megafaunal xenarthrans became extinct at the end of the Pleistocene as part of the end-Pleistocene extinction event.

Cingulata, part of the superorder Xenarthra, is an order of armored New World placental mammals. The armadillos, whose species are split between the families Dasypodidae and Chlamyphoridae, are the only surviving members of the order. Two groups of cingulates much larger than extant armadillos (maximum body mass of 45 kg (100 lb) in the case of the giant armadillo) existed until recently: pampatheriids, which reached weights of up to 200 kg (440 lb) and chlamyphorid glyptodonts, which attained masses of 2,000 kg (4,400 lb) or more.

The cingulate order originated in South America during the Paleocene epoch about 66 to 56 million years ago, and due to the continent's former isolation remained confined to it during most of the Cenozoic. However, the formation of a land bridge allowed members of all three families to migrate to southern North America during the Pliocene or early Pleistocene as part of the Great American Interchange. After surviving for tens of millions of years, all of the pampatheriids and giant glyptodonts apparently died out during the Quaternary extinction event at the beginning of the Holocene, along with much of the rest of the regional megafauna, shortly after the colonization of the Americas by Paleo-Indians.

A rhinoceros (/raɪˈnɒsərəs/ ry-NOSS-ə-rəss; from Ancient Greek ῥινόκερως (rhinókerōs) 'nose-horned'; from ῥίς (rhis) 'nose' and κέρας (kéras) 'horn'; pl.: rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family Rhinocerotidae. It is the only living family in the superfamily Rhinocerotoidea (whose members are also sometimes called rhinoceroses). Two of the extant species are native to Africa, and three to South and Southeast Asia.

Rhinoceroses are some of the largest remaining megafauna: all weigh over half a tonne in adulthood. They have a herbivorous diet, small brains 400–600 g (14–21 oz) for mammals of their size, one or two horns, and a thick 1.5–5 cm (0.59–1.97 in), protective skin formed from layers of collagen positioned in a lattice structure. They generally eat leafy material, although their ability to ferment food in their hindgut allows them to subsist on more fibrous plant matter when necessary. Unlike other perissodactyls, the two African species of rhinoceros lack teeth at the front of their mouths; they rely instead on their lips to pluck food.

A monster movie, monster film, creature feature, or giant monster film is a film that focuses on one or more characters struggling to survive attacks by one or more antagonistic monsters, often abnormally large ones. The film may also fall under the horror, comedy, fantasy, or science fiction genres. Monster movies originated with adaptations of horror folklore and literature.

Arctodus is an extinct genus of short-faced bears that inhabited North America during the Pleistocene (about 2.6 Mya until 12,800 years ago). The two recognized species are the lesser short-faced bear (Arctodus pristinus) and the giant short-faced bear (Arctodus simus). Of these species, A. simus was larger, is known from more complete remains, and is considered one of the best-known members of North America's extinct Ice Age megafauna. A. pristinus was largely restricted to the Early Pleistocene of the eastern United States, whereas A. simus had a broader range, with most finds being from the Late Pleistocene of the United States, Mexico and Canada. A. simus evolved from A. pristinus, but both species likely overlapped in the Middle Pleistocene. Both species are relatively rare in the fossil record.

Today considered to be an enormous omnivore, Arctodus simus is believed to be one of the largest known terrestrial carnivorans that has ever existed. Arctodus, like other bears, was highly sexually dimorphic. Adult A. simus ranged between 300 and 950 kilograms (660 and 2,090 lb), with females clustering at ≤500 kg (1,100 lb), and males around 800 kg (1,800 lb). The largest males stood at 1.67 m (5 ft 5.7 in) at the shoulder, and up to 3.4 m (11 ft) tall on their rear legs. Studies suggest that A. simus browsed on C₃ vegetation and consumed browsing herbivores such as deer, camelids, and tapir. The species preferred temperate open woodlands, but was adaptable, taking advantage of many habitats and feeding opportunities.

Hominins first arrived in the Philippines during a period of lower global sea levels between 1 million years ago (1 mya) to 700,000 years ago (700 kya). Early migrations to its largest island Luzon happened in the Pleistocene and most likely began from the south in Borneo, an island once connected to mainland Asia. From there, hominins crossed narrow sea barriers and reached Luzon by passing through Palawan then Mindoro. The oldest known hominin fossils belong to the extinct Homo luzonensis, which inhabited present-day Cagayan Valley around 67 kya. The species was characterized by its short stature and relatively small brain.

The Philippines' early inhabitants were hunter-gatherers. Apart from wild pigs, deer, and bovines, they hunted a diverse range of large animals like rhinoceros, giant turtles, and elephants. The tools they manufactured were made of stone and were simple, irregularly shaped, convenient, and disposable. Dark-skinned, short-statured, and frizzy-haired peoples called Aytas or Negritos reached the archipelago by about 50–40 kya and were the first anatomically modern humans to do so.

Invasive species are a serious threat to endemic Australian species, and an ongoing cost to Australian agriculture. Numerous species arrived with European maritime exploration and colonisation of Australia and steadily since then. There is ongoing debate about the potential benefits and detriments of introduced species; some experts believe that certain species, particularly megafauna such as deer, equids, bovids, and camels, may be more beneficial to Australia's ecosystems than they are detrimental, acting as replacements for extinct Australian megafauna.

Management and the prevention of the introduction of new invasive species are key environmental and agricultural policy issues for the Australian federal and state governments. As of 2016 the management of weeds cost A$1.5 billion on weed control and a further $2.5 billion in lost agricultural production over the course of a year.